GroupDIY

Project Specific Discussions => Microphones => Topic started by: poctop on September 04, 2012, 01:34:31 AM

Title: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on September 04, 2012, 01:34:31 AM
D-U47FET Build Thread

Let's get those Electron flowing.
All of the info: http://www.groupdiy.com/index.php?topic=49675.0 (http://www.groupdiy.com/index.php?topic=49675.0)

DU-47FET PCB set
(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02a52.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02a7c.jpg)
Fits also Alctron Gt-2b style.

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02a88.jpg)


Not inclued in the Mouser Bom are:


The trimmer in this microphone PCB is no longer necessary , make sure you jump the potentiometer pad contact and use for R6 = 6.8K instead of 3.6K,  the trimmer has been removed from the BOM As well to avoid confusion.


(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02a99.jpg)





BOM: http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=4bdecadc37 (http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=4bdecadc37)

D-U47FET Build Folder:  https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02aab.zip

Schemo Complete: https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02abc.pdf

Schemo PCB A: https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02acd.pdf
Schemo PCB B: https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02ade.pdf


Microphone Body and accessories Available Here :http://www.groupdiy.com/index.php?topic=50015.0 (http://www.groupdiy.com/index.php?topic=50015.0)



This is how it Happened  ;D
D.




(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02af0.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02afd.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b0e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b1e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b2f.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b42.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b53.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b64.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b75.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b86.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02b97.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02ba7.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02bb8.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02bc9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02bd9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02bea.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02bff.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c10.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c21.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c2d.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c3e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c50.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c7a.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c8d.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02c9e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02cae.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02cc0.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02cd5.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02ce5.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02cf9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d05.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d16.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d27.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d38.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d4a.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d5b.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d6d.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d7e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02d8f.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02da1.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02db2.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02dbf.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02dcb.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02dde.jpg)

Microphone output  :)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02def.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02dff.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02e10.jpg)



Validation For GT-2B Style Microphone
Space Left For Transformer , about Length 38mm *  width 50mm approx,  8) :) ;)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02e21.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02e32.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02e43.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02a99.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02e80.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02e98.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02ea9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02eba.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02ecb.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a02edc.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281993864.jpg)



Let me know,

Cheers,
D.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: Scrappersa on September 04, 2012, 05:08:13 AM
Oh man, I would be totally down for one or even two of these! Ah, this would be so amazing.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: KasperNyhus on September 04, 2012, 06:12:32 AM
Yes! That would be sooo cool to have this as a project like your u87!  :P

I have done a little research about micbodys...

u47fet body size is 63mm x160mm but I have not been able to find a body that is spot on yet...

Some sugestions for a original looking clon though:
ADK A-48 71x180
Nady TCM1050 60x180
Omnitronic C-10 60x180
t-bone sct700 58,5x180

Since they are all tube mics the xlr output has to be modded...

This was so much easier with the u87 looking clon...
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: MatthisD on September 04, 2012, 06:26:18 AM
I've been planning to build this circuit for months but can't I can't easily source the megaohm resistors for the pad/low-cut section so it hasn't been a priority. The T.bone sct700 and similar look-alikes seem most suitable but don't have switches.
I was going to use an se2200a(46.5mm internal diameter), cutting the body(shortening by 31mm) to remove the engraved text and then rub off the red graphic. It has two switches(SPDT) for pad and low-cut which are mounted on a PCB like your U67 so I was going to change one of those to DPDT for the pad.
  Now I'm thinking of building it without the switches and with a fixed -10dB pad. I'm also planning on using a 12:1 DI transformer for the output, the Carnhill could be used to incorporate the single winding 50ohm switch but not exactly essential.
Matt.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 04, 2012, 09:35:15 AM
Quote
Since they are all tube mics the xlr output has to be modded...

This was so much easier with the u87 looking clon...

Cool  Suggestions ,  Thanks Guys,  i am planning on doing on here for sure regarding the switches it will have a internal jumper support for SPDT and a some pads to wire the switch if there is any,  i actually not concerned on having a switching in mic body for this but , i know there is the DPDT switch for the PAD -10db and will also have a jumper support for this as well,  i was thinking trying to fit in the Standard taper body but for sure would like more a U47FET look to it ,
wich mic body is the most common and the easier to get at this point ?  :-\
Dan,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 04, 2012, 09:54:40 AM
any toughts about this one,  it has no Switch but looks very cool and it is a 3-pin xlr fitted,
Dan,
Note :  Mxl V89 64*185

Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: KasperNyhus on September 04, 2012, 12:13:40 PM
any toughts about this one,  it has no Switch but looks very cool and it is a 3-pin xlr fitted,
Dan,
wow, that would make a beautiful clon for sure! - now I just have to find a broken one...
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 04, 2012, 02:23:33 PM
Here is a Picture of the Patient  an incomplete U47FET,  it is missing a couple of transistor and also the High Z section,
Briefly alot of Fun ... ;D



Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: 0dbfs on September 05, 2012, 09:53:28 AM
Wow! You are a mad-man!
I'm still trying to catch up with my u1621's and get the 67's going...
Will need to do two of these tho. You know, kick-drums and horn-sections :)

Two doner-mics for $80:
(http://www.bhphotovideo.com/images/largeimages/650167.jpg)
http://www.bhphotovideo.com/c/product/650167-REG/MXL_550_551R_550_551_Condenser_Ensemble_Microphone.html

The larger is 47x170mm

The smaller could be fun for franken-mic'ing too.

Cheers,
j

EDIT: Dany, What are the likely PCB dimensions? MXL Cube would also be interesting but it's 55x120.

Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 05, 2012, 12:50:41 PM
Thanks J,  The PCB dimension are as small as the U1621 but i could permit to have them wider to attached this promising Mxl550, wich is a good deal for sure ,

i will keep you posted   ,  let those nice suggestion like this one coming  ;D

Dan,

Edit: actually checkin on those 550 mxl kit very very cheap look like a winner for the prototype PCB trial for sure, not sure if it could be any better than that at this moment ,
Dany,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: KasperNyhus on September 05, 2012, 02:00:13 PM
Edit: actually checkin on those 550 mxl kit very very cheap look like a winner for the prototype PCB trial for sure, not sure if it could be any better than that at this moment ,
Dany,

Yeah! Definitely a winner for me... A red u47fet - thats gear porn!  :P  ;D
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 05, 2012, 02:30:26 PM
Thanks JB,

Just seen the mxl R144 Kit also ,

http://www.ebay.com/itm/New-in-Box-MXL-R144-Recording-Studio-Ribbon-Microphone-/370645616522?pt=US_Pro_Audio_Microphones&hash=item564c33478a (http://www.ebay.com/itm/New-in-Box-MXL-R144-Recording-Studio-Ribbon-Microphone-/370645616522?pt=US_Pro_Audio_Microphones&hash=item564c33478a)

the kit does not include the Franken mic but there is a nicer shockmount with it it would seems,
it is a little less eye catching  ;D let say,
But well it depends on the intention at this point,   ;D
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: tskguy on September 05, 2012, 02:43:19 PM
Dany,

You know thats a ribbon right, you may find the internal structure may be a bit difficult in terms of mounting a capsule.

Eric
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 05, 2012, 03:33:07 PM
Dany,

You know thats a ribbon right, you may find the internal structure may be a bit difficult in terms of mounting a capsule.

Eric

good point i did not tought off that i really would like to see the inside of an mxl 550 type or alctron gt2B for sure any picture s much welcommed,

Anyone would have some picture of the guts of those type of body ? ? :)



Thanks, :D
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 05, 2012, 07:58:38 PM
ISK Tm-66 ?
dimension Still unknown ?
Dan,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: kante1603 on September 06, 2012, 02:02:39 PM
...and for us german/european guys

http://www.thomann.de/gb/the_tbone_sct700_roehrenmikrofon.htm

Used it with Max's tube version successfully.

Udo.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 06, 2012, 05:45:01 PM
...and for us german/european guys

http://www.thomann.de/gb/the_tbone_sct700_roehrenmikrofon.htm

Used it with Max's tube version successfully.

Udo.

Anyone would have a picture or doc about internal dimension or railing of this Nady or T-Bone mic,
Let me know, :)
Dany, 
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: Spencerleehorton on September 07, 2012, 11:37:22 AM
Hi Guys,

Brian Sowter of sowter transfomers has answered all our prayers and made both the U47Fet transformer and the U67 transformer, both will be available within the next few days:

Type 1303 U47FET
Type 1304 U67
Both will be in 34 mm dia x 24 high cans.

prices will follow soon.

regards

Spence.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: tskguy on September 07, 2012, 12:49:05 PM
Wow very cool.

Cant wait to see more! ;D
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: KasperNyhus on September 07, 2012, 02:29:28 PM
Yeah very very cool!  :D
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: bernbrue on September 07, 2012, 02:37:22 PM
ISK Tm-66 ?
dimension Still unknown ?
Dan,
Hi,
it seems to be the same as the T-Bone SCT-700. It measures 59 x 180 mm
regards
Bernd
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: MicDaddy on September 08, 2012, 11:28:43 AM
I've been sitting on a 'Dale' m7 and this may be just what I was looking for.

Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 10, 2012, 02:33:00 PM
this is i would think the last version,  it 44 * 48 mm , with grapping hole at 1/4" and specific at 28mm center from the bottom of the board,  Meant to  fit tbone, nady and gt-2b style mic   i will be doing a very small run to start with. Let see What happens, 


Let me know if there is any interest. :)
Cheers,
Dan,


Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: KasperNyhus on September 10, 2012, 06:45:38 PM
I'm in for one!
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: signalflow on September 10, 2012, 07:10:38 PM
Holy Crap! You're killin me! I'm in for 2 depending on price. 

-Casey
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: WNStudios on September 10, 2012, 07:13:59 PM
Interested!
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: Tedrummerx on September 10, 2012, 07:37:29 PM
1 please
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: JamesW on September 10, 2012, 08:12:08 PM
A pair please.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: mukole on September 10, 2012, 09:01:49 PM
I'm definitely interested in 2 as well please!!
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: MicDaddy on September 10, 2012, 10:53:55 PM
I'd like 2 please
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: Govinda Doyle on September 11, 2012, 08:48:54 AM
1 for sure!  :D
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: baadc0de on September 11, 2012, 09:01:51 AM
Pair here.. add to the U67/87 boards.

EDIT: One more question, does anyone know if the PCBs would fit into the LDC part (MXL 550) of the MXL pair quoted before?
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 11, 2012, 10:46:57 AM
I beleive the MXL is 47mm outer that should leave enough room for the 44mm PCB but this will be part of the experiment on MXL body type For sure.

DAn,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: MatthisD on September 11, 2012, 11:15:46 AM
I beleive the MXL is 47mm outer that should leave enough room for the 44mm PCB but this will be part of the experiment on MXL body type For sure.

DAn,

The se2200a body is the same diameter. The PCB mounting holes are only 29.5mm apart. I think the 44mm PCB would have to be trimmed down by a couple of mm on each side unless you can mount the PCB right on the centre diameter some how.
Matt
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: 0dbfs on September 11, 2012, 12:51:53 PM
Two for me please!
Thx!
-jb
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: dissonantstring on September 11, 2012, 12:54:19 PM
hi dany,
interested in one DU-47 FETi pcb set. 
thanks!
best,
grant
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: craigmorris74 on September 11, 2012, 01:55:58 PM
I'd like one.

Craig
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: jonhunter on September 12, 2012, 01:15:54 AM
I'd Like two !!

thanks
jon
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: Hank Dussen on September 12, 2012, 02:47:59 AM
1 here!
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 12, 2012, 02:52:32 PM
I beleive the MXL is 47mm outer that should leave enough room for the 44mm PCB but this will be part of the experiment on MXL body type For sure.

DAn,

The se2200a body is the same diameter. The PCB mounting holes are only 29.5mm apart. I think the 44mm PCB would have to be trimmed down by a couple of mm on each side unless you can mount the PCB right on the centre diameter some how.
Matt

The things is i have no clue of the railing dimension inside all i was refered too is the Alctron PCB size and they have been created according to that at this point ,  i did a small batch tough so if they are any correction in term of  dimension i will be open to suggestion no problem,
Dany ,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 12, 2012, 03:04:34 PM
If anyone have a suggestion on makinf this pcb more universally mic body friendly i am open to suggestions as i did put a temporary hold on it to ask this question ,

Let me know as soon as possible ,  i tought i could change the hole or put more hole or something like that ,

Please Let me as soon as you guys Can,

Cheers,
Dany,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: MatthisD on September 12, 2012, 03:51:10 PM
I beleive the MXL is 47mm outer that should leave enough room for the 44mm PCB but this will be part of the experiment on MXL body type For sure.

DAn,

The se2200a body is the same diameter. The PCB mounting holes are only 29.5mm apart. I think the 44mm PCB would have to be trimmed down by a couple of mm on each side unless you can mount the PCB right on the centre diameter some how.
Matt

The things is i have no clue of the railing dimension inside all i was refered too is the Alctron PCB size and they have been created according to that at this point ,  i did a small batch tough so if they are any correction in term of  dimension i will be open to suggestion no problem,
Dany ,

I thought that info might be useful to others if they were planning to use a 47mm body. I'll either do a veroboard job or get a larger body for your PCB thanks.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 12, 2012, 03:59:48 PM
Indeed this is usefull information  :) ,  could you take a picture and dimensioned of the railing,  maybe i could come up with something ,  i really wished those railing be standard in those mic,

Dany,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: MatthisD on September 12, 2012, 04:37:49 PM
I don't know if this body size is the same that other brands use but heres some measurements.
Do you know the price of the Alctron body? also do you know where to get the 220M resistor?

distance between holes
one rail to the other: 29.5mm
between holes on single rail: 35mm

width from one rail to the other,
outside: 37.5mm
inside:29.5mm
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: mouse on September 13, 2012, 09:24:50 AM
possibly in for 2. first time mic project for me and not sure how difficult it will be.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: atticmike on September 13, 2012, 12:02:24 PM
I beleive the MXL is 47mm outer that should leave enough room for the 44mm PCB but this will be part of the experiment on MXL body type For sure.

DAn,

The se2200a body is the same diameter. The PCB mounting holes are only 29.5mm apart. I think the 44mm PCB would have to be trimmed down by a couple of mm on each side unless you can mount the PCB right on the centre diameter some how.
Matt

The things is i have no clue of the railing dimension inside all i was refered too is the Alctron PCB size and they have been created according to that at this point ,  i did a small batch tough so if they are any correction in term of  dimension i will be open to suggestion no problem,
Dany ,

I thought that info might be useful to others if they were planning to use a 47mm body. I'll either do a veroboard job or get a larger body for your PCB thanks.

dunno what you're getting at but the original u47 measures 63mm in diameter and the u87 (just comparing it with a similar build) at 56 / 57mm. Meaning that the U47 was even bigger in both diameter and length. Also, there are lots of big clones out there and well if the pcb is rather small, that wouldn't be too bad since you'd just have to add a little more metal to the pcb holder.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: MatthisD on September 13, 2012, 08:33:40 PM
Also, there are lots of big clones out there and well if the pcb is rather small, that wouldn't be too bad since you'd just have to add a little more metal to the pcb holder.

That would be up to the PCB designer, whether there is enough space to fit the components onto a 27mm or so, useable PCB width. Might be easier not to kill two birds with one stone but whatever pleases the crowd!
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 14, 2012, 12:41:45 AM
updated to final layout,
44 * 48
D.
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: tomas1808 on September 15, 2012, 02:46:29 AM
Poctop,

What about the polarization voltage? Don't you need 60+ volts for the capsule? I am quite a newbie but I know Igor was wondering about this too.

BTW, what capsule would you recomend? Also what FET is the "82808000224" on the schematic?

I too vote for the MXL 550 as a donor body. Its even cheaper on Amazon.com!

Really interested, will probably be my first DIY condenser  8)

Thanks!
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 15, 2012, 04:28:01 PM
Poctop,

What about the polarization voltage? Don't you need 60+ volts for the capsule? I am quite a newbie but I know Igor was wondering about this too.

BTW, what capsule would you recomend? Also what FET is the "82808000224" on the schematic?

I too vote for the MXL 550 as a donor body. Its even cheaper on Amazon.com!

Really interested, will probably be my first DIY condenser  8)

Thanks!

The goal of this project was to recreate the faithfull electronics of the U47FET, and since this mic will be mainly used for Kick drum, Bass Cab and stuff that kick and rocks hard. the 40V polarisation is not an issue at all and will even be favorable to the cause ,  I am mentionning officially that what you see on the U47FET schemo is what you will get  no more no less except  that Circuit will allow Bias for the FET (2N3819) , this is will be a cardiod only mic like the orignal was with a -10db pad,  the capsule based for this project is the K47 Type  as the U47 as well or the predecessor the (ChuckD) M7 capsule ,  but i am sure an M7 capsule will end up in mine ,  I will also be able to utilise the best side of those K47 laying arround.

can't wait to build this and put it in front a Kick Drum,  :P
Cheers,
Dan,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 15, 2012, 04:42:00 PM
Just corrected my previous Post ,  ;)
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: tomas1808 on September 15, 2012, 08:00:49 PM
Still not 100% clear:

Does the original U47 FET use the same capsule as the tube version (K47) but with 40V polarization instead of 60V?

Or does the original simply use another capsule suited for the lower voltage?

In other words, I don't understand if we are building a "100%" clone, or an "hybrid" (in case the original uses a different capsule or somehow manages to rise the polarization to 60V)

Also, how good will this clone be for vocals? I'm looking for a vocal mike  :D

Thanks again!!




Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 15, 2012, 08:16:48 PM
Still not 100% clear:

Does the original U47 FET use the same capsule as the tube version (K47) but with 40V polarization instead of 60V?

Or does the original simply use another capsule suited for the lower voltage?

In other words, I don't understand if we are building a "100%" clone, or an "hybrid" (in case the original uses a different capsule or somehow manages to rise the polarization to 60V)

Also, how good will this clone be for vocals? I'm looking for a vocal mike  :D

Thanks again!!

The capsule is exact same as tube version or the FET it is a standard K47 or M7 type the polarisation with the original schemo is 46.5V  What has been added is a bias point so you dont have to select your FET to match the fix bias value of the original schemo,  What is important for the capsule is to be 72pf not the polarisation voltage,

hope this helps,
Dan,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: tomas1808 on September 15, 2012, 09:33:43 PM
Awesome! That cleared it up.

BTW, there was  a shootout in GearSlutz between the U47 Tube vs FET (among others) and they sounded quite similar.

There was a small difference on the mid-lows, but that was pretty much it.

(I was hearing through sh*tty PC speakers though)

EDIT: Here it is. Check the male shootout.

http://www.gearslutz.com/board/gear-shoot-outs-sound-file-comparisons-audio-tests/601989-classic-vocal-microphones-tube-solid-state-ribbon.html (http://www.gearslutz.com/board/gear-shoot-outs-sound-file-comparisons-audio-tests/601989-classic-vocal-microphones-tube-solid-state-ribbon.html)
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: chrispsound on September 16, 2012, 12:55:44 AM
An Apex 480 seems a proper donor mic for this project and has 3 switches.http://www.ebay.com/itm/New-Apex-480-Wide-Diaphragm-FET-Microphone-Great-Studio-Vocal-Mic-/220824989794?_trksid=p2045573.m2042&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D2077799384241137160%26pid%3D100033%26prg%3D1011%26rk%3D1%26 (http://www.ebay.com/itm/New-Apex-480-Wide-Diaphragm-FET-Microphone-Great-Studio-Vocal-Mic-/220824989794?_trksid=p2045573.m2042&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3D1%26asc%3D27%26meid%3D2077799384241137160%26pid%3D100033%26prg%3D1011%26rk%3D1%26)
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: mrcase on September 16, 2012, 06:01:26 PM
how about that one? doen´t look too bad...
http://www.ebay.de/itm/MC-700-Studio-Kondensator-Mikrofon-Niere-Kugel-Acht-/300779473378?pt=DE_TV_Video_Audio_Mikrofone&hash=item4607da89e2#ht_2989wt_1414
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: poctop on September 18, 2012, 07:30:30 PM
I should be getting a small run next week ,  can't wait to see this thing in action in front a my super kick 24*22
will keep you posted,
dan,
Title: Re: D-U47FETi Microphone Project ( Looking For Donor Body Suggestion Welcomed)
Post by: tomas1808 on September 18, 2012, 07:35:39 PM
I may take one depending on price.
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: tskguy on September 20, 2012, 04:42:23 PM
I would love a to build a pair,  ;D  can I get in on that run coming next week?

Eric
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: lolo-m on September 21, 2012, 01:50:44 AM
Interrested in 2 of them...

And as you asked me, european poeple can post their need in D-U47Fet styroflex sets there :
http://www.groupdiy.com/index.php?topic=49926.0 (http://www.groupdiy.com/index.php?topic=49926.0)
I will certainly organize something for those caps.
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: poctop on September 21, 2012, 08:39:49 AM
Interrested in 2 of them...

And as you asked me, european poeple can post their need in D-U47Fet styroflex sets there :
http://www.groupdiy.com/index.php?topic=49926.0 (http://www.groupdiy.com/index.php?topic=49926.0)
I will certainly organize something for those caps.

Thanks LoLo-M,  this is very appreciated ,
The Bom is ready and should be posted very very soon,
DAn,
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: Scrappersa on September 22, 2012, 06:54:35 AM
I'm in for one as well!
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: berkleystudios on September 24, 2012, 02:02:07 AM
interested in a pair, lets see if my wallet is though haha
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: Jim50hertz on September 24, 2012, 03:04:56 AM
1 for me please Dany  :)
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: signalflow on September 24, 2012, 07:16:16 AM
2 depending on price.

-Casey
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: Dylan W on September 24, 2012, 02:12:21 PM
I've heard that the original U 47 FET was cardioid-only because they used capsules that were out-of-spec on the rear. Is there any reason why, with a fully functional dual diaphragm K47, you couldn't add a simple switch for omni?
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: EvLoutonian on September 25, 2012, 08:44:28 AM
I'm keen.
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: tonycamp on September 25, 2012, 10:56:45 PM
oh...ok, twist my arm, i'm in for 1 also
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: Govinda Doyle on September 28, 2012, 06:30:10 AM
I'm keen for 1!
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: Steph.B on September 28, 2012, 03:37:33 PM
Interested in a pair please !
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: tomas1808 on September 28, 2012, 03:54:44 PM
Any news on the transformers?
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: poctop on September 28, 2012, 06:01:27 PM
Currenlty in Validation in the Lab,  just making sure everything is perfect before i go ahead and release,
So Far very Good is what i can say ,  i am also in discussion with Brian Sower for the transfo but as initially the Transfo is 9:1 and it has a very nice sized core and the bass response out of the mic is very impressive ,

Keep you posted very very soon ,

cheers,  :D ;D :P
Dan,
Title: Re: D-U47 FET Microphone Project PCB ( Coming Next week )
Post by: poctop on September 28, 2012, 11:28:45 PM
This is how it Happened  ;D
D.




(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03110.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03121.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03131.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03142.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03153.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03163.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03174.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03184.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03194.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a031a6.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a031b8.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a031c8.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a031d9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a031e9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a031fa.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0320c.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0321c.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0322d.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0323e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03250.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03262.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0328e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0329f.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a032b0.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a032c2.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a032d3.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a032e3.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a032f3.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03304.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03312.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03322.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03332.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03343.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03355.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03365.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03376.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03386.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03397.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a033a9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a033b9.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a033ca.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a033da.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a033ec.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a033fd.jpg)

Microphone output  :)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0340d.jpg)

(http://dl.dropbox.com/u/43869772/U47/Terrebonne-20120928-00572.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d02819938e4.jpg)
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on September 29, 2012, 03:14:19 PM
Since the Experiment did all go well , i have some pcb for any D-U47FET enthousiast outhere
see the WM,
Dan,  ;)
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: tomas1808 on September 30, 2012, 03:41:48 PM
Poctop awesome work!

BTW, are you sure this will fit the red MXL 550?
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on September 30, 2012, 05:06:10 PM
Poctop awesome work!

BTW, are you sure this will fit the red MXL 550?

At this point No confirmation, i did not have one i hand but the pcb is 44mm width and not very long,
I posted all the dimension of the pcbs in the thread as of now this might help, I ended using it in the U67 body to test but the final destination will be in a gt-2B from Chunger ,  The original Version wich is all tantalum in for polarized caps  is  the default BOM and it is also a bit lower profile than the electrolytics Verison.
Hope this helps,

Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on September 30, 2012, 07:16:48 PM
http://cinemag.biz/mic_output/CM-20110.pdf

This looks like a very nice Chunk of metal to fit this project Needs,

Just a toughts  ;D

D
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: Winetree on September 30, 2012, 11:56:52 PM
Looks like Cinemag offers 2 versions of the output transformer.
100% High Nickel or 50/50 Nickel Steel
Which one?
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: Steph.B on October 01, 2012, 03:07:52 AM
Hi folks,

I've re-read the thread and came aware that Sowter will propose a new transformer for this project (type 1303).

I've just mailed them to have some news about it.

Cheers,
Stephane.
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on October 01, 2012, 08:08:57 AM
Here is the asnswer I got from Brian Sowter ,

1303 (U47 FET).  Ratio 9:1  Impedance ratio 16200/200 Ohms.

1304 (U67).  Ratio 7:1 Impedance ratio 9800/200 Ohms.  Feedback winding 22:1

Both cores are 100% Mumetal.  Expected LF cut off frequency less than 10 Hz for both transformers.
Total Harmonic Distortion better than 0.05% at 50Hz.


I am just not sure about the core size ,  he is expecting some spec sheets soon , will keep ya posted ,

Dany,


Other info from B.Sowter,

I have released these transformers to the works and Ruth will be in contact with a quote.
Type 1303 U47FET
Type 1304 U67
Both will be in 34 mm dia x 24 high cans.


I am sure there is a possibility to have them outside the can if you ask for it ,
this is gonna be fun ,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on October 01, 2012, 08:50:34 AM
Other info from B.Sowter,

I have released these transformers to the works and Ruth will be in contact with a quote.
Type 1303 U47FET
Type 1304 U67
Both will be in 34 mm dia x 24 high cans.


I am sure there is a possibility to have them outside the can if you ask for it ,
this is gonna be fun ,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: EvLoutonian on October 01, 2012, 08:54:02 AM
RAD.
Bring it on.
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on October 01, 2012, 08:55:07 AM
Sorry I guess RAD is good thing is it ?  :-\
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: EvLoutonian on October 01, 2012, 08:59:18 AM
Naturally!
RAD as in Radical, as in "very good, my good man", as in "I like it".
etc

Has anyone found a way of mounting a standard XLR output in the Equinox U47 style body, to suit this kind of standard 48v. build?
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: HellfireStudios on October 01, 2012, 09:29:59 AM
Naturally!
RAD as in Radical, as in "very good, my good man", as in "I like it".
etc

Has anyone found a way of mounting a standard XLR output in the Equinox U47 style body, to suit this kind of standard 48v. build?

Buy a chinese-branded male XLR plug (switchcraft style, not neutrik), and pull out the insert where the pins are attached. It should slide right into your U-47 style body. You could also use an XLR you have laying around to save money.

-James-
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on October 01, 2012, 09:32:22 AM
Some More info on Sowter,


on top W/O can version ,
Bottom Can Version

Both available in 2 style,
hope this helps,
D.
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: Steph.B on October 01, 2012, 01:55:17 PM
That's great news !

Waiting patiently for a quote and availability  8)

Also I think it's better to request the caned version as I think the electromagnetic isolation will be better. Also I think it's better to have leaded wires for soldering for your (awesome) project Dany.
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: EvLoutonian on October 01, 2012, 05:27:30 PM
Buy a chinese-branded male XLR plug (switchcraft style, not neutrik), and pull out the insert where the pins are attached. It should slide right into your U-47 style body. You could also use an XLR you have laying around to save money.  -James-

Cool - that sounds pretty easy, thanks James - I'll try it out in my Equinox body.  Keen to try this U47FET kit.
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: EvLoutonian on October 01, 2012, 05:54:29 PM
Has anyone got the price on the Cinemag transformer mentioned above?
I'm interested to hear thoughts on the Cinemag vs Sowter offerings (as I don't have experience with either - except knowing that both have excellent reputations!).
 
Title: Re: D-U47 FET Microphone Project PCB Build thread ( Now available )
Post by: poctop on October 02, 2012, 08:30:17 AM
D-U47FET PCB 8 set Left
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: WNStudios on October 03, 2012, 12:56:17 AM
I wonder how this would be as a donor: http://www.aurycle.com/aurycle-a620-large-diaphragm-studio-condenser-microphone.html (http://www.aurycle.com/aurycle-a620-large-diaphragm-studio-condenser-microphone.html)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 03, 2012, 05:45:13 PM
I wonder how this would be as a donor: http://www.aurycle.com/aurycle-a620-large-diaphragm-studio-condenser-microphone.html (http://www.aurycle.com/aurycle-a620-large-diaphragm-studio-condenser-microphone.html)

No Clue to find out if the railing is squre is inside but for sure you could benefitiate of the switches,
if i remember well the aurycle inside switch are dpdt wich is nice, you actually need one of these for pad operation , still there is internal jumper as usual but another section where you could possibily add a mini switch on the pcb itself there is a small packgage allowing that on the pcb as another option.
Cheers,
D
Title: Re: D-U47 FET Microphone Project PCB Build thread (transformers?)
Post by: EvLoutonian on October 03, 2012, 07:51:31 PM
Other info from B.Sowter: I have released these transformers to the works and Ruth will be in contact with a quote.
Type 1303 U47FET + Type 1304 U67.  Both will be in 34 mm dia x 24 high cans.

Hi Dan & other U47fet builders!

I got in touch with Sowter and it sounds like the 1303 o/p transformer will be about 50 pounds (approx $80 dollars).  I'm wondering if we could arrange a bit of a group buy and get a better price, if this seems to be a good way to go?

But I'm not sure how many we would need to order to get the price down enough to make it worthwhile doing..

I'm just emailed Brian Sowter to ask for details, and how their transformer is constructed, etc.. 

He said:

1303 is 9:1.
 
We use our normal interleaved winding sections for this transformer.  In this case 2 half primary sections sandwiching the secondary.  This gives an excellent bandwidth with this size of transformer.
 
We do not normally put this type of transformer in a can filled with wax.  Very occasionally we do also apply adhesive to the windings to reduce microphony but do not do so unless the customer asks for it.  In this case I think any microphony would not be a problem as is part of a microphone and the level of signal cause by the transformer would be  minute compared with the microphone itself and perhaps the valve too.
 
Best regards
Brian Sowter
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: tomas1808 on October 04, 2012, 01:49:35 AM
A group buy would be great!

Dont know how many U47FET PCBs have been sold, but I bet we are enough to get a discount.

Poctop? Igor? What are the numbers?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 04, 2012, 09:23:16 AM
I think the group Buy is a good thing ,  but this tranformer is a new release so i bet i would be better to slowly have a feel for the tranformer options ( Cinemag, Sowter , and might AMI come with something soon and i am not talking about the 550$ replica) before we order a bunch od those , i really would like to see many reciepe and then have some comments about those, and take it from there ,  i am sure Brian would like to sell a few to strat with and get some initial feedback first but i might be wrong.
just my 0.02
Again nothing against a group buy but it might be a bit prematured,
Best,
Dan,

 
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 04, 2012, 10:12:01 AM
Hmm, good point, Dan.
I believe Mark Fouxman (SAMAR) may have an appropriate and also excellent transformer for this application.
I don't know which way to go!
Tell me if I'm wrong, but both the Cinemag and Sowter options each seem to be around $80 USD + postage?
I'm not sure how much the SAMAR transformers are.
I believe he does a 9:1 ratio transformer with chambered / interleaved construction, windings soaked and molded in varnish, old school style.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 04, 2012, 04:34:34 PM
Please Feed with some links so we can have a look if possible,
thanks,
Dan,

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 04, 2012, 04:51:16 PM
would also be happy to see SAMAR chime in as well,
all doors open ,
D.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Marik on October 04, 2012, 05:51:42 PM
Hey folks,

Thank you for your interest in our transformers! Yes, we make 9:1, which in construction is quite close to our 10.5:1 replacement for original U87 transformer (if you are interested I can ask for comparison sound samples the studio for whom I made that swap in their 3 U87AI's).

The main difference from all other transformers on the market is that (as already has been mentioned) we mold the turns in varnish, which eliminates distortion associated with mechanical movement of the copper wire along with music signal. This technique was widely used once (ever wondered why old Peerless and Western Electric iron sounds so good?), but not in the modern transformers (or at least we are aware of).

Also, in addition to the interleaving the primary and secondary, in order to reduce winding capacitance we also wind them chambered.

The price is $109, but of course, with group buy the price will go down. If somebody is willing to try it we can make sample transformer and send to audition.

Please let me know if you have any questions.

Best, Mark
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Dylan W on October 04, 2012, 06:20:22 PM
Hey folks,

Thank you for your interest in our transformers! Yes, we make 9:1, which in construction is quite close to our 10.5:1 replacement for original U87 transformer (if you are interested I can ask for comparison sound samples the studio for whom I made that swap in their 3 U87AI's).

The main difference from all other transformers on the market is that (as already has been mentioned) we mold the turns in varnish, which eliminates distortion associated with mechanical movement of the copper wire along with music signal. This technique was widely used once (ever wondered why old Peerless and Western Electric iron sounds so good?), but not in the modern transformers (or at least we are aware of).

Also, in addition to the interleaving the primary and secondary, in order to reduce winding capacitance we also wind them chambered.

The price is $109, but of course, with group buy the price will go down. If somebody is willing to try it we can make sample transformer and send to audition.

Please let me know if you have any questions.

Best, Mark

Mark, I'd be interested to hear those samples!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 04, 2012, 07:29:41 PM
Dan, do you know how many of us there are with the PCB's?  (ie. how many you made initially?)
This will give a better idea of how many people will potentially be looking for a transformer for their build.

Then Mark could offer a better indication of bulk price, for example?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 04, 2012, 07:32:20 PM
Dan, do you know how many of us there are with the PCB's?  (ie. how many you made initially?)
This will give a better idea of how many people will potentially be looking for a transformer for their build.

Then Mark could offer a better indication of bulk price, for example?

about 40 set were sent,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 04, 2012, 09:17:26 PM
Okay, cool.  Thanks for confirming that, Dan.

So, how many of you folks with the U-47fet PCB's are interested to do a bulk buy on a nice output transformer?

I'm in for 2 transformers myself, to go with my PCB sets.  And I'm happy to go with whatever everyone else agrees on, to get the best deal, as I'm sure they'll all be very good transformers.  I am tempted to go with the SAMAR if we can get enough people interested, and we could probably get a comparable price to the others that way.  I've heard glowing reports of Marik's work on his other mic transformers, so I imagine it's a pretty special unit.

Let's hear who's looking, initially, anyway - to gauge numbers?

Keen to hear what others are gonna use for capsules, too!
I have an Equinox Q47 capsule, plus a recent Dale M7 capsule from Cathedral Pipes.  But I've already got these allocated to a couple of tube U47 projects, so I'll prob want to get another pair of capsules for these FET builds!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Winetree on October 05, 2012, 01:41:54 AM
Looking for 2 transformers and capsules.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: tomas1808 on October 05, 2012, 10:51:37 AM
I am in for 1 transformer.

Still no capsule.

BTW EvLoutonian, have you compared the Equinox and the Dale capsules? I know the Dale is considered to be very good, but I haven't heard much about the Equinox.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 06, 2012, 06:45:04 AM
BTW EvLoutonian, have you compared the Equinox and the Dale capsules? I know the Dale is considered to be very good, but I haven't heard much about the Equinox.

Hey!

I haven't had the chance to try either capsule yet, actually.  I bought them for my two tube U47 projects (neither of which I've completed yet) and now I'll need to source two more suitable capsules for the U47fet's as well!

I'm trying to work out what's the best way to go for capsules in the slightly more affordable category to use in my U47fet builds. 

Thinking maybe RK-47 (as offered by microphone-parts) or something else along those lines?   
* For example, maybe the RK7 is their more 'even' or 'vintage' sounding capsule, compared to the RK47?
http://microphone-parts.com/rk7-microphone-capsule/

Have people had good results from these fairly affordable capsules?

I'd especially like to know ~ if anyone has tried the RK47 or RK7 capsules alongside, the Equinox Q47 capsule ~
- how do they compare to each other?   

The B-stock Equinox capsules were sort of comparably priced to the microphone-parts offerings last I checked.

Would it be worth asking Equinox for a group price on capsules?
Or microphone-parts? 

Who thinks they might be in the market for either of these capsules for their current mic builds?

Suggestions for other viable alternatives?

I noticed that Beezneez are currently offering their range of capsules at a reduced rate of $330ea (+GST for us Aussies), which I presume would be fantastic capsules, but I have already spent such a lot of dough on the parts for my MK47 (& EF47) that I don't feel that I can also afford $350 capsules for my U47fet's as well!

Can always be tempted, mind you...


Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on October 06, 2012, 09:41:10 AM
Our good friend Wave recently bought a Mparts k47 for his ioaudio 47 build and he wasnt very pleased. He described it as brittle and wasnt what he was looking for. Granted it wasnt the same circuit but you know 80% of the sound is the capsule. Anyway I am actually going to try and reskin a flea backplate, They actually sell the unskinned backplate and the outer rings as well as the screws for 100 bucks US. If it goes well I may consider reskinng the backplates if someone wants a reskinned flea k47, that being said let me give it a try first and see how it sounds.

Eric
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Marik on October 06, 2012, 06:55:37 PM
Here is the test I was talking about earlier--comparison of two consecutive number U87, one with stock BV13 and another fitted with our replacement transformer. Of course, there is no processing of any kind, except for fade in/fade outs and cutting out all eee, mmm, and so on. The voice:

http://samaraudiodesign.com/U87VoiceStock.wav

http://samaraudiodesign.com/U87VoiceSamar.wav

And me playing some jazz:

http://samaraudiodesign.com/U87PianoStock.wav

http://samaraudiodesign.com/U87PianoSamar.wav

Our good friend Wave recently bought a Mparts k47 for his ioaudio 47 build and he wasnt very pleased. He described it as brittle and wasnt what he was looking for. Granted it wasnt the same circuit but you know 80% of the sound is the capsule.

I had good experience with m-parts K67 capsule and wanted to try their K47. I've never seen K47 to be brittle and the circuit (or even grill construction) could easily do that.

Best, M
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on October 06, 2012, 11:33:12 PM
The Mparts capsules seem to be very good for the price but everything I have heard so far seems to be pretty un pleasing in the upper freaquency range. Thats me comparing it to other capsules in the same body and circuit (u87). Agian the capsules are very nicely constructed I just havent heard one I like yet. To each his own i guess.  Your transformers look and sound great by the way!!

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: OPR on October 06, 2012, 11:49:20 PM
Wow!... Nice work Marik!!   Sounds like you just added an extra octave to the lower end frequency response on those mics!! It's interesting to look at the wave forms on the piano files as you can even see the transients are passing through the transformer unscathed!It reminds me of you Toroidal  ribbon mic transformers when compared to other good transformers Lundahl.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 07, 2012, 08:40:08 AM
The price is $109, but of course, with group buy the price will go down.
If somebody is willing to try it we can make sample transformer and send to audition.  Best, Mark

If my calculations are correct (following an email reply from Marik) he could offer us approx. the following prices on a bulk order:

Order of 10 SAMAR output transformers:  approx ~$92 ea.   (+postage)
Order of 25 SAMAR output transformers:  approx ~$82 ea.   (+postage)

I hope I got that right!

..It's just to give an idea at this stage, anyway..

I understand folks are keen to consider the various different transformer options available, and maybe also wait on some test results from this unit, as well as the new Sowter transformer, etc..  so folks, just pipe up when you wanna go ahead and order something as a group.  I'm obviously keen to get moving along on putting my mic's together (once the PCB's arrive), and that's why I've got amped up about helping to co-ordinate a purchase.
But I don't really know what's the protocol for co-ordinating such an order at this stage - and I don't wanna choke up this thread if it's not the right place for this aspect of the build.

Open to being prodded in the right direction, fellow DIY tinkerers.


Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Marcocet on October 07, 2012, 09:32:03 AM
Personally I'm most interested in the AMI transformers, but without some sort of group buy that will most likely be price prohibitive. I've heard great things about Marik's stuff as well but haven't had a chance to hear any yet. I can't wait for the opportunity! And those prices look extremely reasonable.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 07, 2012, 09:55:53 AM
Personally I'm most interested in the AMI transformers, but without some sort of group buy that will most likely be price prohibitive. I've heard great things about Marik's stuff as well but haven't had a chance to hear any yet. I can't wait for the opportunity! And those prices look extremely reasonable.

I can tell you that Oliver (at AMI) recommends their T49 transformer as an economical alternative for the U47fet.
(compared to their historic spec reproductions, which cost a lot more)
 
He points out that the T49 has nearly the same inductance, and stray inductance, compared with the original.

The T49 is usually $85, but he can offer them to us for $65 ea. for an order of 10+ units as a group purchase at this time. 

Just passing the info on..

For me, spending $70 vs. $100 is not such a huge factor that it would totally dictate my decision - not as much as simply choosing the nicest transformer to do the job - but I'll be glad if we can go in together and get something for around this budget by buying together.

Goodnight!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Le Roux on October 07, 2012, 01:24:50 PM
I'd be in for one AMI transformer.

Neil
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Sredna on October 07, 2012, 07:29:12 PM
+1
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: OPR on October 08, 2012, 10:43:45 PM
Quote
I had good experience with m-parts K67 capsule and wanted to try their K47. I've never seen K47 to be brittle and the circuit (or even grill construction) could easily do that.

Best, M

+1 Me too ..I have used both their rk47 and K67 types Both sound good to me ... Jim Williams also gave them the thumbs up in a Gear Slutz  thread.. Also there are also a few  comercial modders using them in there products..
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Steph.B on October 09, 2012, 02:14:57 AM
Hello,
I've received my PCB's yesterday, thank you Dany !  8)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: wave on October 09, 2012, 08:42:59 PM
Hey guys,
I thought that I should chime in. I didn't get the RK-47 I got the RK-7. I was looking for an M7 type of capsule for my MK47.
Since I couldn't get any response from ChuckD regarding his M7 and the Thiersch was a little out of my price range, I elected to give the RK-7 a try.
I didn't think (and I apologize to tskguy if I communicated this wrongly) that the capsule was brittle. I thought that it was harsh. When I say harsh I mean that it sounded like there was something wacky in the midrange response. Kinda like when you drive a power amplifier too hard and you start hearing the distortion @1K.

The response of the Rk-7 was as advertised. Def dark and not bright like a K67 style capsule but I just didn't like it in my mic.
Eric came by with his first new M7 style prototype on Sunday and we threw it in. His M7 sounded awesome and was what I was looking for, for that mic. I'll let Eric chime in about whether or not he will be offering his M7 commercially but if he does, we will have another great sounding, awesomely priced 100% USA made M7 option.
I had to let my MK47 burn in the other night as I had not done so yet so I will fire it up tomorrow and get some sound samples posted for everyone.

Dave

p.s. Maybe we should create new threads for organizing group buys for transformers and talking about capsules. This is Dany's build thread and I would hate to see it get hard to find pertinent info for building the DU47 FET
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 12, 2012, 12:10:09 AM
Quote
I am mentionning officially that what you see on the U47FET schemo is what you will get  no more no less except  that Circuit will allow Bias for the FET (2N3819) ,

To clear some confusion before it happens the Bias on the U47FET is not actually a Bias , it permits a certain adjustment to the source voltage to operates half the Rail voltage,  it also permitted me to set the FET in a consistant VDS ( about 15V in this case) condition , as i went further into this circuit design with the help of any extraordinary electronician guy who fixes stuff by wetting is finger and touch the PCB  ;D,  to understand the that FET source current is actually regulated by the transistor below and it actually feedbacking to the Drain Voltage for the change in Voltage implying the constant current source , so this design is actually AutoBiasing and regulates a predetermined idle current,  i had noticed no change in the THd Level as well at the oprating point set ,
So basically brings us over a section of the curve where there is not much change in behavior,


So for the Folks who will build, the pot is not really necessary unless you want to learn about the circuit.
if you dont install it just short the 2 used pad with a fine wire and then use R6 = 6.8K there is some extra in the bom anyway as you need a pair to match the front end , the value is not critical,

Best,
Dan,  :)




Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 15, 2012, 03:42:20 PM
Validation For Alctron GT-2B Style Microphone & Railing Test
Space Left For Transformer , about Length 38mm *  width 50mm approx,  8) :) ;)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03dea.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03dfb.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03e0c.jpg)

(http://dl.dropbox.com/u/43869772/U47/PIC%20GT/Terrebonne-20121015-00602.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03e2e.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03e3f.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03e4b.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a03e5c.jpg)

(http://dl.dropbox.com/u/43869772/U47/PIC%20GT/Terrebonne-20121015-00610.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281993907.jpg)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 15, 2012, 05:43:21 PM
Thanks Dan - that's what I wanted to see!
Looking good.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: MatthisD on October 15, 2012, 08:57:05 PM
I have tested my build with the PCBs mounted in a smaller diameter(47mm) body. I tried spreading out the rails to fit the PCB which would have been handy but it was a couple of millimeters too wide for the body so one PCB had to be mounted to a blank piece of board, which took a while to figure out, and then trim both sides down to fit the body.

It worked first time with no problems. All voltages read as the schematic, varying slightly where I have 510K instead of 470k resistors which I don't have any of. The FET section has pads for individual components if not floating that section, as in my case as I'll be changing components there later on. I have a jumper in place of the trimmer, R6: 6.8K and running without PAD or low cut components.
Thanks to Dany for the PCB.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: MatthisD on October 15, 2012, 09:05:04 PM
Response tested with 68pF substituted for capsule and mic preamp for gain and phantom supply.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 20, 2012, 04:02:25 PM
Response tested with 68pF substituted for capsule and mic preamp for gain and phantom supply.

Thanks Matt,  your new mic is already customized a i can see,
Keep us posted  :)
Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 21, 2012, 03:30:45 PM
Merged info tht was on wM ,
Thanks, :)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 22, 2012, 08:37:15 PM
Hi.
We're a little more limited for choice of affordable quality electronic components here in Australia, so I'm trying to get more informed on component choice, for different parts of the circuit (especially capacitors, but also resistors & other parts).

Can someone indicate why would a certain type of cap be chosen for each part of this circuit, especially identifying if there are a few that you'd select the most critically?

I'm not really clear why the majority of cap's on the pre-filled Mouser order form are tantalums. I know I need to replace about 50 of these in my old ARP Omni synth, but presumably new ones installed in a mic in 2012 will be good for another 40+ years!

Thanks!
Evan
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 22, 2012, 08:53:01 PM
Hi.
We're a little more limited for choice of affordable quality electronic components here in Australia, so I'm trying to get more informed on component choice, for different parts of the circuit (especially capacitors, but also resistors & other parts).

Can someone indicate why would a certain type of cap be chosen for each part of this circuit, especially identifying if there are a few that you'd select the most critically?

I'm not really clear why the majority of cap's on the pre-filled Mouser order form are tantalums. I know I need to replace about 50 of these in my old ARP Omni synth, but presumably new ones installed in a mic in 2012 will be good for another 40+ years!

Thanks!
Evan

the original were tantalum and 18pf and 33pf styro , some people like elctrolytic better and others dont,
Even tough i used electrolytics in my demonstration i'd rather stick to the Tants because i love em and i think there suffered from a bad reputation of failure used in the wrong spot , they have better high frequency behavior then the elc but this is all personal taste ,

Check this out here

http://www.electro-tech-online.com/general-electronics-chat/26407-electrolytic-caps-vs-tantalum-caps.html (http://www.electro-tech-online.com/general-electronics-chat/26407-electrolytic-caps-vs-tantalum-caps.html)

From that paper:


Among the advantages [of tantalum] are:
! Small size
! No liquid electrolyte
! Superior temperature stability
! Wider operating temperature range (up to +125°C)
! Long storage (shelf) life
! Larger reverse voltage tolerance
! Low dissipation factor
! Self healing
Aluminum electrolytic capacitors do have several advantages over
tantalum capacitors.
Most prominently:
! Lower cost
! Higher availability
! Shorter production lead times
! Low leakage current
! Higher voltage range (up to 400 VDC)

Some of the most prominent electrical performance differences between
tantalums and aluminum electrolytics
that should be resolved before substituting an aluminum electrolytic for
a tantalum capacitor are:

! Aluminum electrolytic’s higher dissipation factors/ESR, which in turn
reduces their ripple current
capabilities.
! Aluminum electrolytic’s larger capacitance change over temperature.
Electrolytics can change up to six
times more than tantalums.
! Aluminum electrolytic’s capacitance change over frequency.
! Aluminum electrolytic’s changes over time -- up 20% after 2,000 hours
for aluminum electrolytics.

### end quote

There are numerous advantages to using tantalum capacitors over other types of capacitors. First, tantalum capacitors have a higher volumetric efficiency (CV/cc) when compared to other types of capacitors. For instance, a 10-microfarad tantalum capacitor can replace a 100-microfarad aluminum capacitor. Tantalum capacitors are easily mounted onto circuit boards, and give engineering designers the ability to place these components in closely-confined printed circuit board space, as well as utilizing tantalum capacitors' excellent power dissipation characteristics. Second, tantalum capacitors have superior frequency characteristics than many other types of capacitors, including aluminum electrolytics. A comparable CV tantalum capacitor has an ESR ten times better than an aluminum electrolytic capacitor. Third, tantalum capacitors are highly reliable – electrical performance qualities do not degrade over time. Tantalum capacitors do not lose capacitance unlike electrolytic capacitors – in fact, the shelf life for tantalums is regarded as unlimited. Fourth, tantalum capacitors don't wear out – in fact, if there is an imperfection in the dielectric layer of a tantalum, the resistance of the manganese dioxide layer will typically convert to a form that is even more resistive. The new oxide form plugs up the faulty region and results in a reduction in current flow. Finally, tantalum capacitors have an excellent wide operating range, from –55 degrees Centigrade to +125 degrees Centigrade, with a minimal amount of degradation in electrical properties throughout this range.

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on October 22, 2012, 09:54:55 PM
Cool, thanks for the great detailed response, poctop!
MUCH APPRECIATED!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 24, 2012, 02:20:21 PM
I was just messing arround with the idea of mouting the AMI T49 in the U47 FET build and it will work  :) i dont have one here but they are the same package as my T67 shown here just less pin to solder i have used in the demonstration the AMI adaptor board from the D-U67 Project in there is fits like a glove ,
there is actually no AMI adaptor board included for the U47 FET at the moment tough but really nice room for different tranformer , i might consider having one if needed.

Sorry had taken a quick bad picture,
but here it is ,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: tonycamp on November 04, 2012, 10:31:23 PM
Hi Dan, when is the next batch of pcbs coming? I don't know how i missed this, i even posted i was in for 1? ::)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 04, 2012, 10:34:26 PM
Hi Dan, when is the next batch of pcbs coming? I don't know how i missed this, i even posted i was in for 1? ::)

Sorry you have missed it , they are coming this week,
Stay tuned,
Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: gevermil on November 04, 2012, 10:41:24 PM
Hey Dan
Any consensus on the transformer ?
Are you happy with the AMI T49
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 05, 2012, 12:23:02 PM
Hey Dan
Any consensus on the transformer ?
Are you happy with the AMI T49

I am still waiting for My T49 but found that in term of space used in the mic it should just fit in there  :)
can't wait to try it and compare to my 2480 and the original ,
i have to say i was really impressed with the 2480 so far, 
 i might be getting a sowter also question of having more fun ,  i should have the pcb available by tommorow
Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on November 05, 2012, 05:55:09 PM
I'm still up for helping to co-ordinate the group buy of transformers if I know what most people want to go with?
I was just waiting to hear back just how many want to go this way.
We were offered good group discounts.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Jim50hertz on November 05, 2012, 10:04:36 PM
Hey Dan
Any consensus on the transformer ?
Are you happy with the AMI T49

I am still waiting for My T49 but found that in term of space used in the mic it should just fit in there  :)
can't wait to try it and compare to my 2480 and the original ,
i have to say i was really impressed with the 2480 so far, 
 i might be getting a sowter also question of having more fun ,  i should have the pcb available by tommorow
Best,
Dan,

Are you sampling Mark's transformer (the Samar audio)?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on November 06, 2012, 03:04:53 AM
I'd love to hear about results from Mark's SAMAR transformer for this mic, too.  Is someone up for trying both?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mdemesmin1 on November 06, 2012, 02:14:29 PM
  i should have the pcb available by tommorow
Best,
Dan,
[/quote]

Hi Dan,

Im new here, i would really like to tryout one on those PCB.
Who do i need to send the paypal payment to?

Regards;
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 06, 2012, 06:21:22 PM
  i should have the pcb available by tommorow
Best,
Dan,

Hi Dan,

Im new here, i would really like to tryout one on those PCB.
Who do i need to send the paypal payment to?

Regards;
[/quote]


Welcome to the Forum ,  :)

here is the link to get the pcb ,
click on the order button ,

http://www.groupdiy.com/index.php?topic=49675.0

Best
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 06, 2012, 06:29:16 PM
All Pcb available now,
Thanks ,
dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 06, 2012, 08:04:23 PM
Quote
Are you sampling Mark's transformer (the Samar audio)?

It is on my wish list  ,  Actually I have asked Mark to supply some info in the thread ,
Keep ya posted,
Dan,
 
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Tedrummerx on November 06, 2012, 08:05:15 PM
Hey Dan, was there a specific switch you had in mind for the pad when you added that option on the pcb?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 06, 2012, 08:38:04 PM
Hey Dan, was there a specific switch you had in mind for the pad when you added that option on the pcb?

not specifically I knew they were very limited space  ;) , for a miniature dpdt package but it remains internal on the pcb or can be wired this is just an option) or you could wire your own  I beleive mouser have some dip type switches like these if you want intern or you can have one on the mic but not all are dpdt but defaults , So I decided to use the dual jumper config,
anyway my use of the Pad is very predictable so i dont mind taking the extra 2 seconds to configure the mic The jumper can be left inside on the other way so i dont have to worry about the jumper anymore, but the options remains,

Hope this helps,
Best,
DAn,


Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 06, 2012, 10:13:01 PM
Did anybody try fitting it into the MXL 550 type body? Or any other MXL body for that matter?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 06, 2012, 11:04:16 PM
Did anybody try fitting it into the MXL 550 type body? Or any other MXL body for that matter?

I'm currently in the process of trying mine in an mxl 2006, I've bent the rails out to accomodate the boards, which i will also have
to redrill slightly and probably file off about 1mm either side for them to fit, the only real problem is i have an AMI t49 to go with it, and i'm having trouble
figuring how to get that in there, there isn't really enough space for it.

MXL state the diameter of this mic to be 50mm, but the actual body diameter is closer to 47mm so i think any mic with that kind of diameter is going to be
a tight fit.

Also I'm waiting for info from Oliver at AMI on how to use this transformer in the circuit, if anyone else has any info on this feel free to post it, I'm holding off hacking anything until i find out this info.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 06, 2012, 11:09:06 PM
A= RT on pcb
B =BR on pcb
C =BL on pcb
D=  VI on pcb

Hope that helps,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 06, 2012, 11:39:28 PM
Thanks for that Dan,

I'll give it a go this evening,

I'm also curious though, there are 8 pins on the transformer, are only the outer pins used? or are the inner pins paired with the outer pins?

I notice there is windings attached to all of them, this is what was confusing me.

Thanks again,,

Mick
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 06, 2012, 11:52:03 PM
Thanks for that Dan,

I'll give it a go this evening,

I'm also curious though, there are 8 pins on the transformer, are only the outer pins used? or are the inner pins paired with the outer pins?

I notice there is windings attached to all of them, this is what was confusing me.

Thanks again,,

Mick

it is a dual bobin ? but it seems that the drwaing is wrong ,  the primary and the secondary must be wired in series ,,
i believe the scheme is that the primary is on one side pin and the secondary the other side then those pins would need to be tied up on each side,
Hope this helps ,
Dan,


edit: would you be able to take the dcr measurement between A and B you will find out at this moment ,
and if you have a chance that would be interesting to know the dcr resistance of the  primary and secondary once tied up, to get a starter on this one,
Thanks ,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 12:11:02 AM
I believe it is a dual bobbin,

If i check it for DC ohms i get -

325.9ohms  -  A outer pin - C inner pin
7.6ohms   -  A inner pin - C outer pin
324.4ohms- B outer pin - D inner pin
7.6ohms   -  B inner pin   - D outer pin

if that makes any sense to you,
There is no continuity between any other combinations,

As i said i'm pretty confused about this transformer, I have 2 of them and they both read the same,

As to linking up the primary and secondary which pins do you suggest i use for WS,WS,GE and GN?

thanks in advance
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 12:21:10 AM
OK, so if i bridge the inner pins of C and D i get a DC reading of 650ohm across the outer pins of A and B

and if I bridge the inner pins of A and B i get a DC reading of about 15 ohm across the outer pins of C and D

Is this useful? The other combinations wouldn't make sense because that would make it 1:1
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 07, 2012, 12:24:46 AM
OK, so if i bridge the inner pins of C and D i get a DC reading of 650ohm across the outer pins of A and B

and if I bridge the inner pins of A and B i get a DC reading of about 15 ohm across the outer pins of C and D

Is this useful? The other combinations wouldn't make sense because that would make it 1:1

Yes you got it  ,  My original was reading about 717ohm  and 15ohm  IIRC
Best,
dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 12:38:09 AM
OK, so if i bridge the inner pins of C and D i get a DC reading of 650ohm across the outer pins of A and B

and if I bridge the inner pins of A and B i get a DC reading of about 15 ohm across the outer pins of C and D

Is this useful? The other combinations wouldn't make sense because that would make it 1:1

OK, you lost me a little on that drawing,
I tried bridging the centre pins A-B and C-D, using the outer pins put 1 volt AC at 1000hz  into A and B and got 0.132 out of C and D,
in reverse this was about 7.6 volts, I'm not sure if this is right, Its supposed to be 10:1 isn't it?
Maybe there's some loss?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 12:39:51 AM
OK, so if i bridge the inner pins of C and D i get a DC reading of 650ohm across the outer pins of A and B

and if I bridge the inner pins of A and B i get a DC reading of about 15 ohm across the outer pins of C and D

Is this useful? The other combinations wouldn't make sense because that would make it 1:1

Yes you got it  ,  My original was reading about 717ohm  and 15ohm  IIRC
Best,
dan,

Awesome, thanks for your help, I'll let you know how it goes
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 01:01:33 AM
I'm out at the moment, but I'll give that a try when I get home, I'm pretty sure that will give a 1:1 ratio though,

There is a 7.6ohm winding and a 325ohm on each bobbin, and the bobbins run from A to C and B to D.

So I'm pretty sure this would put one of each winding in series on both bobbins,

I'll let you know,

Thanks again
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 07, 2012, 01:02:35 AM
OK, so if i bridge the inner pins of C and D i get a DC reading of 650ohm across the outer pins of A and B

and if I bridge the inner pins of A and B i get a DC reading of about 15 ohm across the outer pins of C and D

Is this useful? The other combinations wouldn't make sense because that would make it 1:1

OK, you lost me a little on that drawing,
I tried bridging the centre pins A-B and C-D, using the outer pins put 1 volt AC at 1000hz  into A and B and got 0.132 out of C and D,
in reverse this was about 7.6 volts, I'm not sure if this is right, Its supposed to be 10:1 isn't it?
Maybe there's some loss?

At this point the official drawing from oliver will be needed,  to make sure it is not an odd ball one ,
forget about my last post i think it did not make sense i and i removed it , need to sleep
but i am the impression my first pic was right, i attached it again ,  8:1 would be what we have here,
so let confirm this with  Oliver,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 08:24:43 AM
Thanks for you help Dan, I've emailed Oliver

Mick :)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 07, 2012, 02:21:24 PM
Thanks for you help Dan, I've emailed Oliver

Mick :)

Post what he says! I think I'm going for one of their transformers and will probably end up running into the same problems. Haha


And for anybody else who missed my post, did anybody successfully fit the pcb and a transformer into the MXL 550?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Marik on November 07, 2012, 03:53:04 PM
Quote
Are you sampling Mark's transformer (the Samar audio)?

It is on my wish list  ,  Actually I have asked Mark to supply some info in the thread ,
Keep ya posted,

Hey Folks,

Thank you for your interest! I am completely swamped with "post AES" catching up. Give me a couple days and I will post the pics, dimensions, and specs.

Best, M
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 07, 2012, 06:52:50 PM
OK, so if i bridge the inner pins of C and D i get a DC reading of 650ohm across the outer pins of A and B

and if I bridge the inner pins of A and B i get a DC reading of about 15 ohm across the outer pins of C and D

Is this useful? The other combinations wouldn't make sense because that would make it 1:1

OK, you lost me a little on that drawing,
I tried bridging the centre pins A-B and C-D, using the outer pins put 1 volt AC at 1000hz  into A and B and got 0.132 out of C and D,
in reverse this was about 7.6 volts, I'm not sure if this is right, Its supposed to be 10:1 isn't it?
Maybe there's some loss?

I would not actually see another way in regards to this drawing here but 8:1 would make the more sense to me  , make sure to ask oliver about the ratio.
Best,
DAn,

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 07:30:10 PM
Just an update,

Oliver has confirmed that this is the correct wiring,
He said the ratio is approximately 9:1 and the inductance values the same as the
FET47 transformer.

Also he's going to get us a drawing in the next day or 2
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 07, 2012, 10:43:36 PM
And here's the updated spec sheet
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 14, 2012, 02:19:59 PM
After hours of trying to get my PCB's and AMI T49 to fit into an MXL 2006 I had laying around i can say
that i don't recommend this body for the FET47.

I made it fit anyway with a bit of hacking to the body and some new holes in the PCB's. Also I had to shorten
the inside pins on the XLR connector to get the transformer in there. It also has no switches.

But I can confirm that the circuit works with with the T49, and the wiring for the T49 is correct as Dan suggested earlier,
I won't comment on the sound yet as i still have the stock MXL capsule installed and am still deciding what to use. I'm
considering the BeesNees K7, or maybe i'll try their chinese K47 for this one.

Also I need to find a better donor for my next build, has anyone else found any good donors yet?

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 14, 2012, 02:21:29 PM
My hack job
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 14, 2012, 03:47:24 PM
Hmm, that makes me a bit concerned about trying a Mxl 550 since it's a bit short and thinner than the 2006. What other donor mic's would work for this Pcb? I would rather not buy the nady/alctron for $200 just for the body.  I'd just build my own body at that point.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: kevinkace on November 14, 2012, 03:55:49 PM
I was looking at the MXL v250, but not sure on the fit (not a lot of info on that mic). The price is right at least.
http://www.musiciansfriend.com/pro-audio/mxl-v250-condenser-microphone
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Dylan W on November 14, 2012, 04:27:24 PM
I have the MXL v250. I thought about using it for this build... the main problem seems to be a lack of transformer housing, though that may not matter. I don't have a ruler nearby but it's not the biggest body in the world. Here's a sloppy inside pic, with some Dostoyevsky for reference  :).



Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Dylan W on November 14, 2012, 04:29:56 PM
And another. The body is the same model as the MXL R44/144 (though the ribbon mics have a transformer bell).
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: kevinkace on November 14, 2012, 04:36:20 PM
Hmm, ya looks pretty tight in there.

I was jut going to mention the MXL R40/R144, but I guess it's also too tight ($69 but comes with shockmount).
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 14, 2012, 06:04:56 PM
Indeed it is pretty tight, there's less than a millimetre to spare,I also shaved about a millimetre
Off the sides of the pcbs to get the cover back on comfortably.
not having a transformer can doesn't seem to be an issue noise wise,
And I don't think you'd get that transformer into one anyway.

I almost scored an mxl 4000 which I think would have been a great donors as it's much larger
But I was too late for that one, there seems to be very few of them around
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 14, 2012, 06:47:40 PM
I literally just bought an MXL 4000 on ebay. I'll let you guys know how it works out! It's supposedly the same diameter as the Alctron but a bit longer. I'm tempted to put my DIY Telefunken 251 into the 4000 but I think I'm going to curb my temptation and just use it on the FET47. The other great thing is the built in switch so I can use it for the pad!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 15, 2012, 02:45:58 AM
Do you guys have any links to where you got the 18pf tantalum and 33pf styroflex in the USA? Or at least the voltages for those two caps.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 15, 2012, 08:22:08 AM
Do you guys have any links to where you got the 18pf tantalum and 33pf styroflex in the USA? Or at least the voltages for those two caps.

I believe some of the guys buy them from this site

http://www.justradios.com/cart.html
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 15, 2012, 12:47:57 PM
Thanks man. Do you know what the minimum voltage for each of those caps should be?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: mukole on November 15, 2012, 02:13:57 PM
The schematic on the first page shows them as 160V which should give a good amount of headroom so if you buy the justradio's
caps they are 630V, they should be fine.
Both the 18pf and 33pf are polystyrene btw, the tantalums are all covered in the mouser BOM.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 15, 2012, 03:21:48 PM
Ah got it, thanks a lot. The only problem with justradios is that it's a $20 minimum purchase and I don't have anything else I need from them. Do you have any other ideas?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 16, 2012, 12:51:27 PM
I literally just bought an MXL 4000 on ebay. I'll let you guys know how it works out! It's supposedly the same diameter as the Alctron but a bit longer. I'm tempted to put my DIY Telefunken 251 into the 4000 but I think I'm going to curb my temptation and just use it on the FET47. The other great thing is the built in switch so I can use it for the pad!

Yes the Mxl 4000 will work  :),  plenty of space also in there.
BEst,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: BigDad on November 17, 2012, 03:07:54 PM
i've a stupid question, why do that ?...

(http://dl.dropbox.com/u/82172012/Terrebonne-20120924-00556.jpg)

... Why not directly soldered on the circuit ?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on November 17, 2012, 03:16:30 PM
well yeah thats really stupid question!  ;D ;D ;D ;D
Just kidding its a good question...its simply to handle high impedance better.
as simply as that.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: BigDad on November 17, 2012, 03:58:54 PM
Thanks, I didn't know that !
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on November 24, 2012, 05:51:59 AM
Hi Guys,

I have done a bit more investigating on donor bodies and these seem pretty good:

Aurcyle A620, Sterling Audio ST51 both are available from amazon really cheap

i just wondered on the sizes inside for mounting the PCB's.

any info very welcome.

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on November 25, 2012, 05:17:58 AM
HI Guys,

for all of my european fellow mic tinkers you may want to check out this mic body:

Pronomic CM-11 Large-Membrane Microphone

http://www.amazon.co.uk/Pronomic-CM-11-Large-Membrane-Microphone/dp/B001KV136I

havnt got sizes yet but could be a good U47 FET mic body? anyone got any sizes?

regards

SPence.

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on November 27, 2012, 03:36:30 PM
Those are all really good suggestions. I wonder if they would fit everything as well.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on November 29, 2012, 02:55:44 PM
Hi Guys,

the Pronomic CM-11 Large-Membrane Microphone wont fit the PCB for the U47 FET.

sorry for suggesting it!! :)

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on December 01, 2012, 09:41:21 AM
Any chance will have to see some completed mic before the end of the world (21 dec-2012),   ;D
just a toughts,    :)
happy building still,   :)
Best,   ;)
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on December 01, 2012, 06:00:09 PM
Hey guys i had a chance to spent some time listening to a D-u47 fet.
Sweet microphone i cant wait to finish mine!!!! im really impressed with how they sound!
Im building mine asap!

Thanks Dany you're a good friend and a nice people!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on December 02, 2012, 07:00:25 PM
Hi Guys,

Im working on building some U47 bodies as per the picture below, also hopefully gonna have an interchangeable head basket U67 style so i can have the U67 guts in it.
Also the middle section can have bits cut out for putting in the switches.
As soon as i get some pictures i'll post up on here.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on December 02, 2012, 07:01:45 PM
This is the other style head basket.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on December 02, 2012, 10:23:03 PM
Any chance will have to see some completed mic before the end of the world (21 dec-2012),   ;D
just a toughts,    :)
happy building still,   :)
Best,   ;)
Dan,

I'll be using either an RK47 or a Dale M7, depending on which circuit I prefer. I'll have it done before too long though  8)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on December 05, 2012, 02:23:55 PM
Any chance will have to see some completed mic before the end of the world (21 dec-2012),   ;D
just a toughts,    :)
happy building still,   :)
Best,   ;)
Dan,

I'll be using either an RK47 or a Dale M7, depending on which circuit I prefer. I'll have it done before too long though  8)

thanks I will stay tuned,
D. :)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Tedrummerx on December 05, 2012, 06:37:18 PM
Any chance will have to see some completed mic before the end of the world (21 dec-2012),   ;D
just a toughts,    :)
happy building still,   :)
Best,   ;)
Dan,

Here's a shot of my 47fet, temporally in the u67 body until the gt-2b comes in. I've only recorded some tambourine, stomps, and a little kick drum so far, which it sounds great on. My only wonder is how it will sound if I upgrade my capsule to something like a ADK k47. It currently has the equinox capsule in it. Fun build, thanks dan! -ted
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Tedrummerx on December 05, 2012, 06:42:27 PM
ignore the ugly transformer board... :)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Tedrummerx on December 05, 2012, 06:43:17 PM
outside
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: BigDad on December 10, 2012, 04:08:56 PM
U47fet finished ! Sound is beautiful ! I'll try to post a demo this week !

Thanks poctop !  ;)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: BigDad on December 16, 2012, 04:29:38 AM
I recorded a little sample of the U47fet !

The U47fet has a CM-2480 and a RK-47 in a T-bone SCT-700's body !

The sample was recorded into bad conditions, no preamp, noise from the audio interface, noise of the computer, bad acoustic of the room, improvisation played badly.

http://dl.dropbox.com/u/82172012/U47Fet%204.mp3 (No Eq, No dynamic processor, just a send reverb)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on December 16, 2012, 05:32:38 AM
The resonant deep "a",does that come from the guitar itself?

Udo.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: BigDad on December 16, 2012, 06:07:29 AM
Yes, that come from the guitar !

The U47fet is one of the few micros happens to well defined this guitar without low-cut, which keeps low frequencies. Usually with others mics, the sound is confused and unclear !
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on December 17, 2012, 10:52:45 AM
the store will be open today only and then back Jan 7th 2013
Thanks all,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on December 28, 2012, 01:42:18 AM
Hey all,
Having some trouble at first fire-up. Just getting a loud and steady low-frequency hum at the output. Everything appears to be assemble correctly, but obviously I need to look a little closer. What your first guess when getting nothing but ~60 cycle hum?
thanks!
JS
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: pasarski on December 28, 2012, 07:34:54 AM
Hey all,
Having some trouble at first fire-up. Just getting a loud and steady low-frequency hum at the output. Everything appears to be assemble correctly, but obviously I need to look a little closer. What your first guess when getting nothing but ~60 cycle hum?
thanks!
JS

Testing with the body/headbasket off? That's the 1st guess  :)

2nd: something isn't assembled correctly, bad joint, something touching the body that shouldn't etc.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on December 28, 2012, 12:40:09 PM
Quote
Testing with the body/headbasket off? That's the 1st guess  :)

2nd: something isn't assembled correctly, bad joint, something touching the body that shouldn't etc.

Thanks, Pasarski. I was testing with the body off. I am brand new to microphones, and have some things to learn. I assumed that since I had continuity between pin 1 of the xlr to the GND pad on the PCB that I was OK, even with the body tube off.
The mic is working clearly and quietly now.
Pin 1 is connected to the mic body on the donor body I used (MXL 4000). Does the mic body do anything besides act as a shield when connected to Pin 1?


Another question for the group - I was unable to match transistors at home. Where in the circuit is it particularly important to match transistors and resistors? Any simple suggestions for matching the transistors?
thanks.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: HellfireStudios on December 28, 2012, 03:37:30 PM
Quote
Testing with the body/headbasket off? That's the 1st guess  :)

2nd: something isn't assembled correctly, bad joint, something touching the body that shouldn't etc.

Thanks, Pasarski. I was testing with the body off. I am brand new to microphones, and have some things to learn. I assumed that since I had continuity between pin 1 of the xlr to the GND pad on the PCB that I was OK, even with the body tube off.
The mic is working clearly and quietly now.
Pin 1 is connected to the mic body on the donor body I used (MXL 4000). Does the mic body do anything besides act as a shield when connected to Pin 1?


Another question for the group - I was unable to match transistors at home. Where in the circuit is it particularly important to match transistors and resistors? Any simple suggestions for matching the transistors?
thanks.

The body also protects the electronics and keeps the mic user safe from shock(tube mics run at high voltages).

There is only one transistor in that circuit. Are you referring to capacitors?

As far as I know, the capsule needs to be matched more so than the circuit, but matching the IDss of the 1N3819's you intend to use would put them at a similar setting for volume and headroom.

-James-
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: muffy1975 on December 31, 2012, 09:17:43 AM
Hi guys,

don't know if this is the right place to ask but..... my fet 47 has a low output. 20db down from a tlm103 ( which is a very sensitive mic naturally).

i have  just put together a fet 47 using the schematic and what i can make out from the layout provided here and.........

1. a RK7 capsule,
2. a peluso BV8PS xformer with the 11:1 and 5.5:1 option. ( which i bought of Sir POCTOP ). I'm using the 11:1 option of course.


The output seems kinda low. I'm sure the 10db pad is not engaged. The spec sheet for the fet 47 original says it has a sensitivity of 8mV/PA which should make it 10db quieter the a TLM 103 at 23mV/PA ( this mic i have for comparision ). However the output is 20db quieter than the TLM 103.

Is this correct? or is the problem likely to be.......

1) the xformer which at 11:1 is not quite right?

2) the 2n3819 is biased wrong or something. Should i add the 25k trimmer that you guys have and play with than in series with a 3.6k resistor?

3) the use of a polystyrene 2200pf cap? what effect would changing this have?


The sound of the microphone is ok. It's full range. Sounds good on a bass drum but sounds very 4-5K on the vocal and lacks a little bit of bass, maybe believe it or not. ( maybe thats the xformer. It's also very directional.


Is everything ok with this microphone?

Many thanks in advance for any help or pearls of real DIY MIC wisdom

Michael
oxford
england
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on December 31, 2012, 01:08:29 PM
My mic sounded a bit thin and also had a fairly low output at first. In my case the problem was that I had wired up the rear diaphragm to the backplate connection on the pcb. I hadn't realized that the backplate is actually the middle part of the capsule. After I disconnected that and ran a wire from one of the screw holes on the side of the capsule to the "back" connection on the pcb the mic came to life.
I can say that the mic seems to be working great with the 2200pf film cap and with the jumper installed in place of the trim pot.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Biasrocks on December 31, 2012, 01:13:32 PM
Are you getting signal on + / - sides of the XLR?

That would account for 6db if it's unbalanced.

Maybe check the transformer wiring/output.

Regards,
Mark
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on December 31, 2012, 02:03:00 PM
Make sue your Transistor are properly oriented so easy to make a mistake and with the part number as well double check that ,
the pot + the 3.6K resistor permits to set VDS conditions but as explained it does not make a difference cause it feeding back to self bias.
you can jump it plus the 6.8K resistance if you are not sure . if you have it installed then you can check that you can have a VDS of about 15V ,

double check  the voltage in the schemo as well, might help to find the spot,

Hope this helps,
dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: muffy1975 on January 02, 2013, 10:43:05 AM
hey guys,

thanks for getting back.

here are some voltages. do these look good?

on the 2n3819 T1 i have

drain=  40.3v
source =  25.1v

on T2 i have

E= 25.1
B= 23.7
C = 0.62

on T3 i have

E=44.5v
B=30.2v
C=40.3

T4 i have

E= 20.7v
b=21.4 v
c= 24v

T5 i have

E=43v
B=41.8v
C=21.5v


on T6 i have


E=0v
B=0.6v
C=21.6v



T7 i have


E=44.3v
B=44.6v
C=46.4v


and 15.8v from the 10m resistor to the junction with the 1g resistor.



how does it look to you guys ?


the capsule is connected properly. one diaphragm connected to 1g and the polystyene 2200pf cap. and the middle bit to earth.

not sure how to test the ac across xlr 2 and 3 cos of the 56r resistors. do i test before these?

man thanks in advance



michael
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 03, 2013, 05:58:52 PM

At a quick glance it seems fine from here ,  can you check capsule polarisation volatge and xlr and also traffo config  ,   check the capsule orientation also and switching config if used

hope this helps ,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: muffy1975 on January 05, 2013, 05:58:55 AM
Hey Dan,

i switched to using the  other side of the capsule and nothing has changed. my 100m resistor is hard wired to point BB on the schematic.

The voltage on the gate of the 2n3809 is 4V. That doesn't say much. The Drain is 40V


where do i measure capsule polarization voltage? is it where the 1g resistor meets the 2200pf cap or is it at the gate of the fet? Also, how do i measure the xlr. IS it AC across pins 2 and 3 ? or is it AC between ground and PIN 1 and PIN 2 then PIN 1 and PIN 3?

Many thanks again

Michael
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 05, 2013, 04:25:01 PM
Hey Dan,

i switched to using the  other side of the capsule and nothing has changed. my 100m resistor is hard wired to point BB on the schematic.

The voltage on the gate of the 2n3809 is 4V. That doesn't say much. The Drain is 40V


where do i measure capsule polarization voltage? is it where the 1g resistor meets the 2200pf cap or is it at the gate of the fet? Also, how do i measure the xlr. IS it AC across pins 2 and 3 ? or is it AC between ground and PIN 1 and PIN 2 then PIN 1 and PIN 3?

Many thanks again

Michael

you can measure the polarisation voltage on the back side of R1 ,  the microphone output is suppossed to be in the range of the u87 maybe a litle hotter but not like 20db thats make no sense ,  i would also verify the board wire hookup also , what is your capsule like ,
hope this helps
Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on January 05, 2013, 09:10:34 PM
Hey dan you alright?? Sent you an email few days ago but no answer.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: muffy1975 on January 06, 2013, 04:20:01 PM
hey dan,

the voltage between r1 and the R8 = 15.2v. relative to earth is that correct?

if not here, the what should it be in volts?

what seems to be happening is a mix up on the original schemo with the voltages to R16. Should that not be 45v to  R16  and there be 46.5 going to T7?

michael
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 07, 2013, 04:00:38 PM
hey dan,

the voltage between r1 and the R8 = 15.2v. relative to earth is that correct?

if not here, the what should it be in volts?

what seems to be happening is a mix up on the original schemo with the voltages to R16. Should that not be 45v to  R16  and there be 46.5 going to T7?

michael

I believe it should read the polarisation voltage there 45V DC , I had to to put aside my 47FET circuit away for the M49 coming , i will try to hook it back and take some reading when i have a chance ,
I will keep you posted,

Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 07, 2013, 04:00:54 PM
The Store is back online,

Happy New year All,
Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: muffy1975 on January 07, 2013, 05:08:01 PM
does anyone know exactly where on the circuit you would measure the polarization voltage for  the capsule?

it can't be after R8. That's a 10m resistor. Surely. How can 40v+ get there?

Many thanks for any help

Michael
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: MatthisD on January 07, 2013, 06:01:58 PM
You mentioned the transformer can be wired 11:1 or 5.5:1, is there four leads/or pins on the primary? do you have a wiring diagram for it?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on January 08, 2013, 01:14:47 PM
Here's some photos of my recently completed Fet47 and an audio clip.


On acoustic guitar:
https://www.dropbox.com/sh/hfq2uaj7230vdgj/3uzuNH4c-o (https://www.dropbox.com/sh/hfq2uaj7230vdgj/3uzuNH4c-o)

I tried to go high-end on this. I found a re-skinned Neumann K47 on ebay (from seller alphaville777, who usually has one or two listed). I also got the direct replacement Fet 47 transformer from AMI, who had it in stock. All the electronic components are from the Mouser cart and the JustRadios capacitor cart. Total cost was about $1,350. Much cheaper than a vintage Neumann, or a modern Fet47 reproduction...

I found that the MXL 4000 body works great for this project. I got one on ebay for $140. Everything fit very well. A couple tips for using this mic body:

Spray paint to taste.

[/list]

I haven't had a chance to put the mic in front of a drum kit yet. The audio clip is a few seconds of acoustic guitar.

The mic isn't very hot. In the clip the mic is less than a foot from the guitar, with 65db of gain from a GML 8304 preamp. Maybe I've done something wrong here? I took my best guess at the transformer wiring, and went with the way that had the fullest (but not the loudest) sound.
Another thing I would like to learn about is picking the transistors. There are a lot of spares in the Mouser cart, which I assume are there so you can pick and match the best ones.

Great project, Dan! I think that putting my DIY energies into microphones is going to be the best way to improve the quality of my recordings. Very exciting.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 08, 2013, 02:07:23 PM
thanks SkidmoreBay taking time to do this, The Clip just got that Vibe  8) awesome ,

The mic is not supposed to be very hot as overgained modern mic  ,  as a single stage FET driving circuit as in vintage U87 circuit.
this vintage circuit will give about 10-12db less than modern mic , this allow the preamp to give its full color range when using this type of vintage circuit and also more headroom on loud source as Bass Cab and front kick mic,  i would really like to hear a clip of your mic in front of a bass cabinet  :),
the transformer should wired 9:1 primary to secondary.

Best,
Dan,



Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poolshark on January 09, 2013, 05:31:23 PM
Hey,

Brand new to this forum and pretty new to DIY projects in general but this looks like an awesome project.  Thank you Dan! 

The link to the Alctron GT-2B shows a body with a large "bulb" where the transformer would go at the base of the body.  Is this section removed when the mic is switched to a three pin XLR out?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 09, 2013, 05:34:16 PM
Hey,

Brand new to this forum and pretty new to DIY projects in general but this looks like an awesome project.  Thank you Dan! 

The link to the Alctron GT-2B shows a body with a large "bulb" where the transformer would go at the base of the body.  Is section removed when the mic is switched to a three pin XLR out?

you just need the 3-pin xlr insert that comes with Chunger body kit.  you can swap it easy.
see here ,

http://www.groupdiy.com/index.php?topic=50015.0

Best,
DAn,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Winetree on January 09, 2013, 05:38:35 PM
Yes, That's the transformer. It will be replaced with another one.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poolshark on January 09, 2013, 05:49:16 PM
Awesome, thanks!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: LarryChicken on January 09, 2013, 10:43:29 PM
Just finished my U47fet today. It sounds great. Didn't get to do much testing with it other than some vocals but the midrange is so present and I feel like instruments will sit in the mix nicely.

I am using an old SE Z-2200 as a doner mic along with an RK47 from Microphone-parts and a Peluso BV8p transformer. I'm not sure if this is the transformer but as previously mentioned, I'm not 100% on the bass output. It just seems a bit thin. I guess I may have to go to AMI for their t49.

(http://i221.photobucket.com/albums/dd73/jeffs789/IMG046_zpsf6a1f5ff.jpg)

(http://i221.photobucket.com/albums/dd73/jeffs789/IMG044_zpsce15a15a.jpg)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 09, 2013, 10:48:17 PM
Quote
I'm not sure if this is the transformer but as previously mentioned, I'm not 100% on the bass output. It just seems a bit thin. I guess I may have to go to AMI for their t49.


Try reducing the Value of C1 to something like 1000pf-500pf to see,
Let me know
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 09, 2013, 10:58:43 PM
Oh man. I'm having massive issues with my build. I'm using the ami t49 transformer. No audio is passing but when I short the transformer by touching a pin with my finger, it starts making crazy popping sounds and occasionally I can hear my voice for a split second but it quickly fades out. I keep checking everything over and the only thing I'm unsure of is my transformer wiring. In your diagram Dan, a and b and c and d are reversed from what's actually printed on the transformer. I've tried switching it around but I'm the same issue. Could It be that I haven't usea jumper on any of the pad or lc pads? I can post some pictures tonight but where would you guys start looking?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 09, 2013, 11:17:41 PM
The traffo is from pin view in the image but that should not change the a b c d on the transformer right , I will have T49 Shortly here and i will make sure it is the correct connection Can you measure the resistance between A-B and C-D that will tell whats what.

so the transfo connection would be

A- to  RT
B- to BR
C--to BL
D- to VI


Do you mean that the info on the website is wrong again  :o ,  so you primary is C and D
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on January 10, 2013, 12:02:20 AM
Sorry to interrupt the troubleshooting...

Dan asked me how I liked the mic and how it sounded. Here's some info on that, at least for a mic with the components I used (Neumann K47 and AMI Fet47 transformer):

It seems to have big low end (but it's not woofy sounding), and it's got a little bit of a high frequency lift but it's not edgy.

The two large-diaphragm condensers I have are a Peluso 2247 and a Neumann M149. I have also used a Shure KSM44 a lot. Compared to the Peluso 2247, I think it has a cleaner, less colored sound. I think I like it better on acoustic guitar because of that. The low end is a lot tighter also. The M149 is a very bright and powerful mic. This mic is a lot mellower than that, but I think that is going to make me like it more on some sources. It's not as brash in the mid-range either. Compared to the KSM44, I would say that this mic is way warmer.

This is based on just a short time using the Fet 47. I haven't had a chance to put it in front of a bass cabinet or kick drum yet.

It was definitely a great project to take on as my first microphone build. The most exciting part for me has been to see that I can build a high-quality mic myself, for a lot less money.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 10, 2013, 04:03:26 AM
(http://i.imgur.com/ghjN1l.jpg)

(http://i.imgur.com/jW8v5l.jpg)

(http://i.imgur.com/9c1vVl.jpg)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 10, 2013, 05:38:54 AM
I have all of my connections wired as:

A- to  RT
B- to BR
C--to BL
D- to VI

I also took out the trim pot and bridged the connection. Replaced R6 with a 6.8k resistor. I'm not getting any signal except occasionally this weird popping thing happens where it makes a really loud clipping pounding sound over and over again until I turn off the mic. It's almost as if it's building up energy and then finally starts popping. Maybe a grounding issue? I checked all of my transistors and they seem to be in the right place. The polarity of all of the caps are good too. Hopefully my pictures are clear enough but let me know if you guys need to see anything else. I've been working on this all day and can't seem to get to the bottom of this.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on January 10, 2013, 09:52:13 AM
Quote
I also took out the trim pot and bridged the connection. Replaced R6 with a 6.8k resistor. I'm not getting any signal except occasionally this weird popping thing happens where it makes a really loud clipping pounding sound over and over again until I turn off the mic. It's almost as if it's building up energy and then finally starts popping. Maybe a grounding issue? I checked all of my transistors and they seem to be in the right place. The polarity of all of the caps are good too. Hopefully my pictures are clear enough but let me know if you guys need to see anything else. I've been working on this all day and can't seem to get to the bottom of this.

I wonder if the problem is with your capsule. I'm not sure how this works, but I've read on this thread that some people checked their circuit with a small capacitor in place of the capsule. I think that would allow you to trace the circuit with an oscilloscope and tone generator, if I understand it right.
Anyone care to explain how that would work?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 10, 2013, 02:19:40 PM
I would be happy to try it with a cap in place. What value would you guys suggest?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 10, 2013, 03:18:15 PM
Quote
I also took out the trim pot and bridged the connection. Replaced R6 with a 6.8k resistor. I'm not getting any signal except occasionally this weird popping thing happens where it makes a really loud clipping pounding sound over and over again until I turn off the mic. It's almost as if it's building up energy and then finally starts popping. Maybe a grounding issue? I checked all of my transistors and they seem to be in the right place. The polarity of all of the caps are good too. Hopefully my pictures are clear enough but let me know if you guys need to see anything else. I've been working on this all day and can't seem to get to the bottom of this.

I wonder if the problem is with your capsule. I'm not sure how this works, but I've read on this thread that some people checked their circuit with a small capacitor in place of the capsule. I think that would allow you to trace the circuit with an oscilloscope and tone generator, if I understand it right.
Anyone care to explain how that would work?

Does it look like my transformer is hooked up correctly?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 10, 2013, 03:54:12 PM
Quote
I also took out the trim pot and bridged the connection. Replaced R6 with a 6.8k resistor. I'm not getting any signal except occasionally this weird popping thing happens where it makes a really loud clipping pounding sound over and over again until I turn off the mic. It's almost as if it's building up energy and then finally starts popping. Maybe a grounding issue? I checked all of my transistors and they seem to be in the right place. The polarity of all of the caps are good too. Hopefully my pictures are clear enough but let me know if you guys need to see anything else. I've been working on this all day and can't seem to get to the bottom of this.

I wonder if the problem is with your capsule. I'm not sure how this works, but I've read on this thread that some people checked their circuit with a small capacitor in place of the capsule. I think that would allow you to trace the circuit with an oscilloscope and tone generator, if I understand it right.
Anyone care to explain how that would work?

Does it look like my transformer is hooked up correctly?

Make sure your link A to F are Solid continuity , that might be your problem here ,  remove the capsule and check all the schematic reference voltage that is usually the way to start  troubleshooting ,  relating the reading you sent me A B primary 648 ohm and secondary C D 15 ohm is correct so the infomation above is correct . double check also the polarity of tantalum cap they are polarized also. Check you that you have a proper ground from F to the mic body and then pin 1 also .
 from the picture also it could be a cold solder joint ,  just a tip for the future, on soldering,  try to use less solder and focus on what the solder does when the proper temperature is reached just put a touch on it and if you see the solder penetrating in the pad and form a nice little cone then this will help your future build garantueed you'll see when experience come in  ;) also from the picture make sure you dont have pad or connection from the pcb touching the rail this will do it bad.

hang i there ,
Best,
dan,




Hope this helps,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 10, 2013, 04:51:52 PM
Just finished my U47fet today. It sounds great. Didn't get to do much testing with it other than some vocals but the midrange is so present and I feel like instruments will sit in the mix nicely.

I am using an old SE Z-2200 as a doner mic along with an RK47 from Microphone-parts and a Peluso BV8p transformer. I'm not sure if this is the transformer but as previously mentioned, I'm not 100% on the bass output. It just seems a bit thin. I guess I may have to go to AMI for their t49.

(http://i221.photobucket.com/albums/dd73/jeffs789/IMG046_zpsf6a1f5ff.jpg)

(http://i221.photobucket.com/albums/dd73/jeffs789/IMG044_zpsce15a15a.jpg)

This is a very nice example of a super clean build super nice work,   try reducing C1 to 500pf to see if it will react better with your transformer combination.
Congrats.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on January 10, 2013, 11:01:38 PM
from the picture also it could be a cold solder joint ,  just a tip for the future, on soldering,  try to use less solder and focus on what the solder does when the proper temperature is reached just put a touch on it and if you see the solder penetrating in the pad and form a nice little cone then this will help your future build garantueed you'll see when experience come in  ;) also from the picture make sure you dont have pad or connection from the pcb touching the rail this will do it bad.

hang i there ,
Best,
dan,




Hope this helps,
Dan,
+1 on this!
In the first pic it looks like nearly none of the solder joints have been hot enough or better said the solder did not "flow".Some joints also have a certain amount of dirt on their top.You should really keep your solder iron tip as clean as possible.
Zooming in seems to show a lot of residual flux,not good for a build of this kind!

Udo.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 10, 2013, 11:10:24 PM
I would recommend this solder to all my friends, as well this might help you with soldering in the future , just the best stuff i have ever encountered in this world
perfect for mic building
Hope this helps,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: LarryChicken on January 12, 2013, 12:18:24 AM
Just finished my U47fet today. It sounds great. Didn't get to do much testing with it other than some vocals but the midrange is so present and I feel like instruments will sit in the mix nicely.

I am using an old SE Z-2200 as a doner mic along with an RK47 from Microphone-parts and a Peluso BV8p transformer. I'm not sure if this is the transformer but as previously mentioned, I'm not 100% on the bass output. It just seems a bit thin. I guess I may have to go to AMI for their t49.


Just an update here. The lack of bass was due to the fact that the steel of my transformer was touching the side of the metal holder at the bottom of the mic. This must have changed the frequency response and introduced some excess distortion in the signal. So I wrapped the trans in electrical tape and the mic now sounds great.

As far as the sound is concerned I can say that this mic will sound good on SOME types of vocals but not all. This is mainly a factor of the high frequencies being rolled off by the k47 type capsule. Leave vocal duties to the k67-based mics. But where this mic shines is literally everything else. Every instrument I put it in front of is translated in a clean, and present form. There are no extraneous frequencies, only a natural transcription of how it sounds in real life. Speaking from limited expeirience, I've never heard a better recording of my acoustic guitar. The mid range is so richly captured that it's almost too good to be true. And the bass response is full, focused and muddiness does not exist (which is why it's used for bass instruments, I suppose). Maybe I'm just in the honeymoon phase but I really can't see myself leaving this mic in its case every session like I did before the upgrade. I can't wait to try it on guitar amps, bass amps, drum room, and even classical intruments.

Thanks to Dan for the great work on the PCB and all the help along the way.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 12, 2013, 04:53:14 AM
Quote
I also took out the trim pot and bridged the connection. Replaced R6 with a 6.8k resistor. I'm not getting any signal except occasionally this weird popping thing happens where it makes a really loud clipping pounding sound over and over again until I turn off the mic. It's almost as if it's building up energy and then finally starts popping. Maybe a grounding issue? I checked all of my transistors and they seem to be in the right place. The polarity of all of the caps are good too. Hopefully my pictures are clear enough but let me know if you guys need to see anything else. I've been working on this all day and can't seem to get to the bottom of this.

I wonder if the problem is with your capsule. I'm not sure how this works, but I've read on this thread that some people checked their circuit with a small capacitor in place of the capsule. I think that would allow you to trace the circuit with an oscilloscope and tone generator, if I understand it right.
Anyone care to explain how that would work?

Does it look like my transformer is hooked up correctly?

Make sure your link A to F are Solid continuity , that might be your problem here ,  remove the capsule and check all the schematic reference voltage that is usually the way to start  troubleshooting ,  relating the reading you sent me A B primary 648 ohm and secondary C D 15 ohm is correct so the infomation above is correct . double check also the polarity of tantalum cap they are polarized also. Check you that you have a proper ground from F to the mic body and then pin 1 also .
 from the picture also it could be a cold solder joint ,  just a tip for the future, on soldering,  try to use less solder and focus on what the solder does when the proper temperature is reached just put a touch on it and if you see the solder penetrating in the pad and form a nice little cone then this will help your future build garantueed you'll see when experience come in  ;) also from the picture make sure you dont have pad or connection from the pcb touching the rail this will do it bad.

hang i there ,
Best,
dan,




Hope this helps,
Dan,

Thanks for the help guys. It is now working due to my wonderful and amazing friend Nathan.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 13, 2013, 09:58:38 AM
Quote
Thanks for the help guys. It is now working due to my wonderful and amazing friend Nathan.

Can you let us know what was the issue as it could help others as well, 

Congrats to you and Nathan for both your perseverance,
Best,
Dan
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 13, 2013, 02:40:44 PM
Be reminded that the U47FET is SuperCardiod and not Cardiod that contributes to make it sounds very focused and tight but with a nice low end and also Special
 :)
Best,
Dan,
 
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 14, 2013, 02:46:53 AM
I am completely embarrassed but it was my horrible soldering. I need to get a nicer soldering iron and to learn how to properly do it.

I had a session today and used your FET47 with a Peluso 47 capsule on the outside of the kick and an RE20 on the inside. Man, it was absolutely incredible. I love the combination. Thank you for the wonderful design.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on January 14, 2013, 03:14:16 AM
Congrats,

nice to hear you got it up and working!

Cheers,

Udo.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on January 22, 2013, 01:03:20 AM
I just tried Dan's suggestion of changing the size of C1 to 1000pf to see how it affects the bass response. All I can say after a limited test on acoustic guitar is that this didn't seem to cause a major change in the sound of the mic (on acoustic guitar...). I put the 2200pf cap back in after the test.
I will definitely be interested in trying this again when I get a chance to record a real bass instrument or kick drum to see if it adds any thing. The low end on my mic seems really nice. So far as I can tell there isn't a need to alter the schematic to address thin sound - at least with the capsule and transformer I used (Neumann K47 and AMI 47fet).
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Winetree on January 25, 2013, 02:50:48 AM
What do you do with the inside parts after you strip them out of the GT-2B mics.
The transformers, PSB with tubes, Capsules. Going to replace them all.
Same with the 7 pin cable. Was going to use it for the DU-67s,
but went with the Gotham GAC-7.
Try to sell them or throw them away?
I don't know if I'll ever use them.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on January 29, 2013, 02:24:27 AM
I just tried the Fet47 on bass this last weekend. I just want to say that it is beautiful the way it captures the bass. Absolutely beautiful. I used a T49 transformer from AMI and a Peluso capsule. Thanks for making this possible. The fet47 has been one of my dream mics for a long time and to make the entire thing for under $400 (luckily already had the capsule!) is just unbelievable.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: LarryChicken on February 03, 2013, 01:37:57 AM
I just tried the Fet47 on bass this last weekend.

Did you use it on a bass amp or acoustic?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Scrappersa on February 03, 2013, 01:45:44 AM
15" electric bass cab. Pretty loud source too.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: khstudio on February 07, 2013, 07:21:55 PM
Just ordered a PCB a few days ago & was wondering if you got my order & if it shipped out yet?

Thanks
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on February 07, 2013, 07:44:11 PM
Danny is à Nice guy, dont worry, i know him on person.
Besides he ships once à week i think.. you should get your stuff soon.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 07, 2013, 09:16:22 PM
Just ordered a PCB a few days ago & was wondering if you got my order & if it shipped out yet?

Thanks

yes Shipped February 4 th,

Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: khstudio on February 07, 2013, 09:27:42 PM
Very cool!!! Thanks guys.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poolshark on February 09, 2013, 03:05:25 AM
Just got mine as well, thanks Dan!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: khstudio on February 12, 2013, 12:25:27 AM
Question about Transistors:

I have several BC184C but no "B"... the HFE is a little higher.
Will they work OK or do you think they'd be too out of spec or worse, make the mic not work or "sound" as it should?

I also don't have BC212 but do have some BC214... "Same question as above"

Thanks,
Kevin
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 12, 2013, 03:46:30 PM
Question about Transistors:

I have several BC184C but no "B"... the HFE is a little higher.
Will they work OK or do you think they'd be too out of spec or worse, make the mic not work or "sound" as it should?

I also don't have BC212 but do have some BC214... "Same question as above"

Thanks,
Kevin

you can go higher HFE but not Lower ,  that is why they specify a minimum value sometimes to ensure the proper amplifier overall gain ,
Best,
Dan,
   
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on February 22, 2013, 02:59:25 AM
Hi Guys,

thought i'd post something of me using the U47 FET and U67 in a recording.

http://www.facebook.com/pages/Emily-and-Spence/423697837714350?sk=app_204974879526524

The U47 FET was on the acoustic guitar with a tiny bit of compression from an ART Pro VLA.
The U47 FET has a sowter 9610 transformer in it with a RK47 capsule.
On vocals I had the U67 with erics capsule K67 with Sowter 1303 transformer in it and Telefunken EF86 red dot silver plate.
Had 2 U87's in the room and mixed them in a little for ambience and also a Golden Age R2 with a Sowter 8074 transformer in it over the violin.
Would be interested in what people think.

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on February 22, 2013, 06:50:18 AM
Sounds great Spencer
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Jim50hertz on February 22, 2013, 08:12:26 AM
Hey Spencer

I don't have a Facebook account, can you post a direct link or Soundcloud it?

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 22, 2013, 08:18:11 AM
Hi Guys,

thought i'd post something of me using the U47 FET and U67 in a recording.

http://www.facebook.com/pages/Emily-and-Spence/423697837714350?sk=app_204974879526524

The U47 FET was on the acoustic guitar with a tiny bit of compression from an ART Pro VLA.
The U47 FET has a sowter 9610 transformer in it with a RK47 capsule.
On vocals I had the U67 with erics capsule K67 with Sowter 1303 transformer in it and Telefunken EF86 red dot silver plate.
Had 2 U87's in the room and mixed them in a little for ambience and also a Golden Age R2 with a Sowter 8074 transformer in it over the violin.
Would be interested in what people think.

regards

Spence.

AAAAAAAAsome Just woke up and listen to it and sounds so sweet and creamy,  this will be a nice day ,
not sure if this is all of D-mic models but i just dig it so much ,
Thanks for doing this , 
Best,
Dan,
 
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on February 22, 2013, 08:20:17 AM
Hi Guys,

yeah i'll try and get them all to soundcloud.
Yes Dany they are all your pcbs!! sound pretty good to me!!.

regard

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 22, 2013, 08:22:27 AM
Hi Guys,

yeah i'll try and get them all to soundcloud.
Yes Dany they are all your pcbs!! sound pretty good to me!!.

regard

Spence.

is the other tune are same setup because i just listening i am so much enjoying this ,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on February 22, 2013, 08:30:49 AM
It was all done live within 45 minutes, emily the singer only had an hour, so we setup the mics she came round and me and emily just played the songs, rough mix, and bounced down.
that was it!!

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on February 22, 2013, 04:50:02 PM
Wow, very nice!! makes me smile!! ;D

She has a great voice,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: adeptusmajor on February 23, 2013, 12:09:44 AM
Hi Guys,

thought i'd post something of me using the U47 FET and U67 in a recording.

http://www.facebook.com/pages/Emily-and-Spence/423697837714350?sk=app_204974879526524

The U47 FET was on the acoustic guitar with a tiny bit of compression from an ART Pro VLA.
The U47 FET has a sowter 9610 transformer in it with a RK47 capsule.
On vocals I had the U67 with erics capsule K67 with Sowter 1303 transformer in it and Telefunken EF86 red dot silver plate.
Had 2 U87's in the room and mixed them in a little for ambience and also a Golden Age R2 with a Sowter 8074 transformer in it over the violin.
Would be interested in what people think.

regards

Spence.

I'll qualify this response by saying that I'm listening on laptop speakers and I just returned home from blasting my ears out for 3 hours running sound for a fully orchestrated "rock musical"...

I think the instrumentation has a nice, natural sound and room tone that fits the vibe of the arrangement pretty well.

The vocals are well executed and have a nice tone, but something about it doesn't sound right to me. What kind of effects chain, if any, are you running on the vox? Sounds like maybe it's a little over compressed, or has a strange EQ curve. It just doesn't seem to really sit with the sound of the instruments to me, but again my ears are ringing right now so I may think different in the morning.

Very nice job overall.


EDIT: I only listened to the "Isn't She Lovely" rendition before posting
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on February 23, 2013, 03:13:13 AM
HI Guys,

thanks for your feedback, as per the sound of the vocals, its was U67 into valve channel of allen & heath desk gs3000 desk with Art Pro VLA on the insert into 96i interface into Protools HD 9.
Compression wise there wasnt a lot on there, threshold at around 0db and 2:1 and on auto.
On the meters it was only just compressing a little.
I would be interested in Tskguys comments on the vocals now as i did think first of all the capsule was a little dark, but i did compare it with my C12 which i normally use for female vocals which has the high end nice and open but the aim here was to use all the mics made from Danys pcbs.
I am open to tweaking the U67 further as it may well be its not quite there yet.

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on February 23, 2013, 03:28:44 AM
hi guys,

here is a soundcloud link for anyone who doesnt have a facebook account.

http://soundcloud.com/spencer-lee-horton/sets/emily-spence-live-demo

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: wave on February 23, 2013, 01:26:55 PM
I kind of thought that her vocal has a tad too much in the 800 Hz area. I like the high end; it's got that silky HK-67 sound. I would like to hear her do it again with the DU-67 into a 1272 type preamp. Maybe the signal chain has too many tube stages (DU-67, valve pre and VLA).
IME too many tube stages can have a negative impact. Maybe you could do one with the mic, into a normal channel of the mixer and no VLA to compare.
Everyone has their opinions and I have never been a fan of the Art VLA.

Emily has a really cool timbre to her voice and I think the DU-67 is a perfect mic for her. The FET47/ACG combo was nice too. What is your mic technique for the ACG? Do you mic 6" away around the 12th fret...etc?

Just my 2¢
Dave
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 24, 2013, 11:25:23 AM
Hi All , 

Last week i received a call from Dave at Cinemag and he was telling me that he has been working for the last 6 months on an authentic reproduction of the FET 47 Transformer and suddently one of those beauty came down my mail box  :) and i put it against the original that i have here  and seriously i could not make the difference in sounds between the 2 of them  at a point where i put the original on Ebay  today , Dave asked me what i tought of the transformer before actually making it available for other folks , (Dave ---- I guess this answer your question) ,   here is the the Cinemag CM-13101 split lamination of nickel and cobalt   8) and Faraday shield.,   I just wanted to let you the know the headsup on this ,
Many Thanks to Dave at Cinemag for his amazing work and kindness.
Feel Free to drop him a line if you have any questions.  [email protected] (http://[email protected])
Enjoy !

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281993b70.jpg)

Best,
Dan,


Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on February 24, 2013, 11:53:39 AM
Hi Wave,

As per try what you have suggested i will try recording her vocals into a normal channel and do the same through the valve channel.
As per the Art Pro Vla, i have had this modded and it has pretty good valves in there, so to my ears at least i think this sounds good, but its no CL-1 :)
Acoustic guitar wise it was pretty much like you said 6" away somewhere between the 12th fret and the sound hole.

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: useme2305 on February 24, 2013, 02:57:34 PM
does anyone know if the MXL R144/R44 ribbon mic body is suitable for the D-U47FET project?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 24, 2013, 03:06:36 PM
does anyone know if the MXL R144/R44 ribbon mic body is suitable for the D-U47FET project?

Do you have the internal dimension of the Mic in question that might help , i think it is big enough  are the railing tapered or squared in this one ,
d
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: useme2305 on February 24, 2013, 03:17:51 PM
unfortunately i don't have any dimensions cause i don't have one here.

here are some pics.
http://www.gearslutz.com/board/6952589-post7.html (http://www.gearslutz.com/board/6952589-post7.html)
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 24, 2013, 03:21:16 PM
unfortunately i don't have any dimensions cause i don't have one here.

here are some pics.
http://www.gearslutz.com/board/6952589-post7.html (http://www.gearslutz.com/board/6952589-post7.html)

i am affraid the answer is no but you should check out the mxl4000 somtimes they comes as repair on ebay and you get them for cheap ,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: useme2305 on February 24, 2013, 03:49:26 PM
ah, too bad. it's so nice n tiny.

the MXL4000 looks cool too....can i repurpose the switch somehow for the D-U47FET build so i don't have an ugly useless hole in the mic?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 24, 2013, 03:56:37 PM
ah, too bad. it's so nice n tiny.

the MXL4000 looks cool too....can i repurpose the switch somehow for the D-U47FET build so i don't have an ugly useless hole in the mic?

I think there is even a  dpdt switch in the 4000 for the pad and the spdt for Low cut ,  i know some folks have been using it with sucess the railing is the same size as the pcb and there room for transformer no doubt about it ,
D
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: wave on February 24, 2013, 07:55:34 PM
That is a very nice transformer!

Dave
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Melodeath00 on February 25, 2013, 10:36:35 AM
Can anyone tell me how close the Alctron GT-2B body is to the real U47 FET? Would an Equinox U47 body be closer? Would this PCB fit the Equinox 47? Thanks!

Also, does this FET need to be bias adjusted like the U87?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 25, 2013, 11:58:10 AM
Can anyone tell me how close the Alctron GT-2B body is to the real U47 FET? Would an Equinox U47 body be closer? Would this PCB fit the Equinox 47? Thanks!

Also, does this FET need to be bias adjusted like the U87?
Quote
A
The pcb is same width as the mk47 so it it will fit inside no problem with a large transformer and the 47FET is self bias I added a pot just to set some fine tune vds condition that you don't have to worry you can jump the pot and use 6k8 For R6
 
No bias to. Execute
Dan
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Melodeath00 on February 26, 2013, 01:51:24 PM
Thanks poctop! I guess I'm also wondering how close the GT-2B headgrille is to the U47FET. From what I understand, the U47FET headgrille is the exact same as the U47 tube headgrille. Will the capsule be slightly obscured by the top bar of the GT-2B headgrille? Is it three-layer like the U47 headbasket?

If I get the Equinox body, is it easy enough to install an XLR connector instead of the included Binder connector? Thanks so much!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: useme2305 on February 26, 2013, 02:56:10 PM
if you don't find a way to convert the EQU47 body to XLR out you can still easily make your own Binder to XLR cable.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Winetree on February 26, 2013, 05:16:00 PM
going with the AMI T-49 transfo. GT body, PSB with Mouser Bom parts, Styro Caps
going to hook it up with the stock capsule and see what that sounds like?????
What's the best Capsule with this combo?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 26, 2013, 07:33:36 PM
Thanks poctop! I guess I'm also wondering how close the GT-2B headgrille is to the U47FET. From what I understand, the U47FET headgrille is the exact same as the U47 tube headgrille. Will the capsule be slightly obscured by the top bar of the GT-2B headgrille? Is it three-layer like the U47 headbasket?

If I get the Equinox body, is it easy enough to install an XLR connector instead of the included Binder connector? Thanks so much!

The Headbasket of the GT-2B is indeed 3 layer mesh but that all i can say ,  once the capsule in the headbasket some of the top portion capsule hidden by the headbar.

Here is the relative fit of the FET 47 in comparaison with the M49b  all the space is required  so an mxl144 would not do it,  the transfo is 1.5" X 1.39"
to give you an idea.



(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281993b8e.jpg)

Best,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on February 27, 2013, 02:35:35 PM
Hi Guys,

here are a few more sound samples from when I first plugged in the U47 FET.
Drums were recorded one U47 FET in front of the kick drum in the middle, not in front of the sound hole, in the middle of the drum about 4-5 inches away. (eq'd in protools, took all the top end off and boosted at 50hz and raise the low end a little)
The overhead was to the right of where i sat on the drum with the U47 FET above my head pointed at the snare.
The Cello had the U47 FET point at the F holes on the bottom and a SE1A about head hight point at the middle of the fret board, then the level mixed in.
Both recordings have a little bit of compression on them, and no EQ apart form the kick drum.
A little verb on each as well.

Bear in mind these were slapped together pretty quickly!!!, let me know what you guys think.

https://soundcloud.com/spencer-lee-horton/sets/u47-fet-testing

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Melodeath00 on February 27, 2013, 02:45:42 PM
One more quick question. I just noticed this build doesn't seem to have switches. Were those parts of the U47FET circuit ignored? Is it possible to add switches to the PCB and just have the switches inside the body? Or were the switches left off the pcb totally? Thanks a lot for putting up with my ignorance haha
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 27, 2013, 08:25:10 PM
found that on another thread he Dave Grohl Mic bass drum technique with a U47FET,  tought i'd post it here,
Best Realized with a supercardiod mic Like the FET47

Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 27, 2013, 08:26:28 PM
One more quick question. I just noticed this build doesn't seem to have switches. Were those parts of the U47FET circuit ignored? Is it possible to add switches to the PCB and just have the switches inside the body? Or were the switches left off the pcb totally? Thanks a lot for putting up with my ignorance haha

you can wire a switch to pcb or use the internal jumper setting for pad and Low Cut if needs be,
Best,
D
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: kevinkace on February 27, 2013, 09:06:01 PM
found that on another thread he Dave Grohl Mic bass drum technique with a U47FET,  tought i'd post it here,
Best Realized with a supercardiod mic Like the FET47

Dan,
What is going on there!? Look at all the mic cables going into that love tunnel! I'd sure like to know...
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 27, 2013, 09:15:43 PM
found that on another thread he Dave Grohl Mic bass drum technique with a U47FET,  tought i'd post it here,
Best Realized with a supercardiod mic Like the FET47

Dan,
What is going on there!? Look at all the mic cables going into that love tunnel! I'd sure like to know...

+1  at least some mic cable are going in there so it cannot be misinterpreted
 ;D
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Spencerleehorton on March 01, 2013, 08:14:47 PM
Thought i'd re post this to see what people thought.

Hi Guys,

here are a few more sound samples from when I first plugged in the U47 FET.
Drums were recorded one U47 FET in front of the kick drum in the middle, not in front of the sound hole, in the middle of the drum about 4-5 inches away. (eq'd in protools, took all the top end off and boosted at 50hz and raise the low end a little)
The overhead was to the right of where i sat on the drum with the U47 FET above my head pointed at the snare.
The Cello had the U47 FET point at the F holes on the bottom and a SE1A about head hight point at the middle of the fret board, then the level mixed in.
Both recordings have a little bit of compression on them, and no EQ apart form the kick drum.
A little verb on each as well.

Bear in mind these were slapped together pretty quickly!!!, let me know what you guys think.

https://soundcloud.com/spencer-lee-horton/sets/u47-fet-testing

regards

Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Tommy Radonicus on March 01, 2013, 09:14:25 PM
These sound good.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on March 11, 2013, 06:23:51 PM
heres my version!!
its on the works yet! it features a cheap capsule and a cheap transformer.....
However im not ready to test as theres 2 resistors missing...

Thanks.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Tommy Radonicus on March 11, 2013, 07:07:30 PM
These sound really good Spence.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on March 16, 2013, 12:18:53 PM
Heres my completed DU47Fet.
Its really a great sounding microphone, even with a cheap capsule and transformer.
Actually the transformer who is actually a mic pre transformer , I got it from a Christmass thread back in 2008 was a prototype by Ed Anderson, built by Edcor, ratios are at 1:10 if im right, i know is Ed Anderson cuz it says EA on one side.

Capsule got it from a Studio Projects B1 wich i got for free from someone.

Body is a MXL4000 that Dany kindly offered me!

Thanks once again to Dany for his efforts to capture better sounds!


Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on March 16, 2013, 12:21:15 PM
body.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: LesPaul on March 29, 2013, 03:36:29 PM
ChuckD is letting go of some B-stock M7's with slightly higher capacitance than the usual ones (120-190pF, usually 90-120pF). Is it possible to use these in the u47FET, and which adaptations needs to be made?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: HellfireStudios on March 29, 2013, 06:51:46 PM
You could see if anyone around here could re-skin that type of capsule.

-James-
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 29, 2013, 08:34:38 PM
ChuckD is letting go of some B-stock M7's with slightly higher capacitance than the usual ones (120-190pF, usually 90-120pF). Is it possible to use these in the u47FET, and which adaptations needs to be made?

the U47FET mic is probably the most forgiveable mic on this type of capsule , and at Chuck liquidation price i think that worths the bet,
My 0.02
Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 29, 2013, 08:43:17 PM
A thread about that ,
here,

http://www.groupdiy.com/index.php?topic=51391.0
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Tommy Radonicus on March 30, 2013, 07:53:52 PM
ChuckD is letting go of some B-stock M7's with slightly higher capacitance than the usual ones (120-190pF, usually 90-120pF). Is it possible to use these in the u47FET, and which adaptations needs to be made?


The advice on the other thread seemed to be "Try it and see" ..  ;D
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: LesPaul on March 31, 2013, 12:30:27 PM
ChuckD is letting go of some B-stock M7's with slightly higher capacitance than the usual ones (120-190pF, usually 90-120pF). Is it possible to use these in the u47FET, and which adaptations needs to be made?


The advice on the other thread seemed to be "Try it and see" ..  ;D

I might as well do that:)

Would the MXL 2006 be suitable for this build? It has a width of 50mm, which should be good enough. But I don't know the height.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on March 31, 2013, 12:38:43 PM
Boards are square not the same form like the 2006 type.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: LesPaul on March 31, 2013, 01:57:57 PM
Boards are square not the same form like the 2006 type.

Thanks

I see that some guy here tried it, and made it fit. Doesn't seem like the best option, though.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on April 07, 2013, 10:27:16 PM
Another one up and running
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: Winetree on April 08, 2013, 03:38:44 AM
MicDaddy, What capsule are you using?
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on April 08, 2013, 08:35:27 AM
MicDaddy, What capsule are you using?

ChuckD's M7.  Sits a little high in the headbasket and sounds wonderful.   

I populated the trimmer and tweaked by ear some with no discernible change in audio.

Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 08, 2013, 04:13:04 PM
MicDaddy, What capsule are you using?

ChuckD's M7.  Sits a little high in the headbasket and sounds wonderful.   

I populated the trimmer and tweaked by ear some with no discernible change in audio.

thanks Micdaddy,  your are correct to say that it sits a tad high, in my 49b that i just put the M7 in i had to remove the top screw because it go it contact with my backplate on the headbasket and my pattern did not work,    took a good 5 minutes until i figured out  ;)
thanks For your post ,

Best,
Dan,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 08, 2013, 05:59:37 PM
Quote
I populated the trimmer and tweaked by ear some with no discernible change in audio.

the trimmer on this build will not affect the sound but more a tad in the VDS of the FET,  just a tad, and since it is self bias type circuit it should not affect the sound at all,

the trimmer can be easily omitted as per the 1 page procedure with no adverse affect on the sound at all,

best,
DAn,
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on April 09, 2013, 10:02:43 PM
The GT-2B blasted down.  The front grille mesh didn't care for such abuse and did start to curl in around the outer edges as it isn't adhered entirely around the lip, only spot welded with solder.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on April 09, 2013, 10:08:06 PM
Powder painted matte black. 

A warning regarding these head-baskets.  They are literally held together entirely with solder. 

During the outgassing process, I discovered the hanger naked and the head-basket in pieces at the bottom of the oven.  I had to do a lot of desoldering and reconstruct the thing with a loctite.
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: HellfireStudios on April 09, 2013, 11:26:36 PM
The capsule seems to be a bit high. The headbasket ring might interfere with proper pickup.

-James-
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on April 09, 2013, 11:48:39 PM
The capsule seems to be a bit high. The headbasket ring might interfere with proper pickup.

-James-
Hi James,

in the original build the capsule does sit very high in the basket,about one third behind the upper ring.Look here (scroll down a bit,you'll see what I mean):

http://www.jogis-roehrenbude.de/Roehren-Geschichtliches/Neumann-Mikro/U47/U47.htm

As long as it doesn't touch the top mesh I'd say it's o.k..

Cheers,

Udo. ;)

Congrats MicDaddy btw.!
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 13, 2013, 03:53:50 PM
For those that will be building the mic project that needs the 0.01uf  capacitor in the package 5*11mm  i have been able to change mouser minds to offer a 10% variation at a minimum qty of 1  ;),

here is a link for it ,
http://ca.mouser.com/ProductDetail/Vishay-Roederstein/MKT1813310405/?qs=N5kmjX/bzE4Fjs7uA0EePA==

i aslo went over my BOM and added in the customer part number cell some nice subsitution for the parts that went back order , should be all good now ,

Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 06, 2013, 05:25:31 PM
Hey all,

I wanted post some pictures of my newest microphone!! Thanks to my good friend Wave (he built it!) I also have a bit of news regarding a capsule as well... Its a new capsule I am selling that works in any of the mic's that use a 47 or m7 style capsule.
I had a RK7 capsules laying around so I thought I would  do a comparison, the first clip is the 47fet with a RK7
Second clip is my H20 capsule. Its a bit of a 47,67, hybrid. I personally think its sound great. No pop screen and I am about 3-4 inches away. Let me know!
Another cool thing is a new TX available from Cinemag. http://cinemag.biz/mic_output/PDF/CM-13101.pdf
Its sounds fantastic and is true to the original TX Dany was directly involved with its creation.
Clip 1 RK7
https://dl.dropboxusercontent.com/u/55530129/47fetRK7capsule.wav
Clip 2 H20
https://dl.dropboxusercontent.com/u/55530129/47fetTSKcapsule.wav

(http://i280.photobucket.com/albums/kk187/tskguy/2013-05-06073305.jpg) (http://s280.photobucket.com/user/tskguy/media/2013-05-06073305.jpg.html)
(http://i280.photobucket.com/albums/kk187/tskguy/2013-05-06073106.jpg) (http://s280.photobucket.com/user/tskguy/media/2013-05-06073106.jpg.html)
(http://i280.photobucket.com/albums/kk187/tskguy/2013-05-06072926.jpg) (http://s280.photobucket.com/user/tskguy/media/2013-05-06072926.jpg.html)
(http://i280.photobucket.com/albums/kk187/tskguy/2013-05-06072906.jpg) (http://s280.photobucket.com/user/tskguy/media/2013-05-06072906.jpg.html)

Eric
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KasperNyhus on May 06, 2013, 06:21:09 PM
Hi guys
I have a problem with my u47fet build. Unfortunately it sounds very thin.
I read that someone earlier had a similar problem due to the trafo touching the house, but I have checked and double checked for that.
I made the following sweep and it clearly shows the problem

https://dl.dropboxusercontent.com/u/14107936/u47fet%20sweep.MOV (https://dl.dropboxusercontent.com/u/14107936/u47fet%20sweep.MOV)

Does anyone of you know what might cause all this trouble?

/Kasper
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 07, 2013, 04:56:34 PM
Did you check all of the voltages?? Do you have the roll off inadvertently switched on?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 07, 2013, 11:35:04 PM
Hey guys,

Her is a little guitar track I just did, please forgive the crappy playing I am drummer!!!
https://dl.dropboxusercontent.com/u/55530129/47fet%20Guitar.wav

I think it sounds pretty darn nice, Its was recorded through my ssl9k in to my ssl converters at 44.1 no eq or anything else.
Man I dig this mic!! Thanks to Dany again for a great project, it sounds really great in my opinion. I cant wait to hear it on some other sources.

Eric
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on May 08, 2013, 08:56:08 AM
Do you guys know how to install à Chuck M7 in the fet47?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on May 08, 2013, 10:37:34 AM
Do you guys know how to install à Chuck M7 in the fet47?

I marked and punched the very center of the circular metal disc -which holds the stock capsule- then drilled using a bit to accommodate the m7 mount screw.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 08, 2013, 11:38:49 AM
Tuff crowd  :-\


Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: HellfireStudios on May 08, 2013, 12:06:10 PM
Hey guys,

Her is a little guitar track I just did, please forgive the crappy playing I am drummer!!!
https://dl.dropboxusercontent.com/u/55530129/47fet%20Guitar.wav

I think it sounds pretty darn nice, Its was recorded through my ssl9k in to my ssl converters at 44.1 no eq or anything else.
Man I dig this mic!! Thanks to Dany again for a great project, it sounds really great in my opinion. I cant wait to hear it on some other sources.

Eric

I really like the clarity. A little too much pick noise for my tastes, but it's not the mic. It's just placement to my ears.

-James-
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on May 08, 2013, 12:10:53 PM
What about the hookup?
Does the red cable means front capsule?? What should i do with the rear wire then?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 08, 2013, 02:50:34 PM
The 47fet is Cardioid only so you only need to make the front capsule and backplate connection. Sadly the back side isnt used in the 47fet.

Eric
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 08, 2013, 02:59:21 PM
The 47fet is Cardioid only so you only need to make the front capsule and backplate connection. Sadly the back side isnt used in the 47fet.

Eric

Correction supercardiod only
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on May 08, 2013, 03:37:29 PM
Yep, there is a small lobe at the back.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on May 08, 2013, 03:50:19 PM
OK, I listened to the spoken samples. Eric's new capsule sounds more detailed for sure. But in all fairness, the RK-7 is a dark sounding capsule. It was made to have more treble roll off than the RK-47. And I'd say that Eric's capsule is a little brighter than a regular K47 (first impression, mind). To me it not only looks, but also sounds like a cross breed between the K47 and K67. What I'm trying to say is that the added treble as opposed to the RK-7 helps the sound being more detailed. That said, after EQ-ing the RK-7, I think Eric's would still sound more classy.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 08, 2013, 03:53:57 PM
If you guys like the mic i do still have a couple of PCB left  ;)
and some corresponding styroflex cap kit.

Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 08, 2013, 05:01:28 PM
Micaddict

Yes I would agree with on all fronts! I actually thought the Microphone parts rk7 sounded pretty good in this mic, it sounded pretty bad in the mk47 tube mic Wave built. My capsule does have a bit more air up there... I am attaching a frequency chart that actually is comparing my capsule in a G7 circuit against an original u47 with a neumann 47 capsule!! I completely understand its not the best comparison but you can at least see the plot.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on May 09, 2013, 08:09:48 AM
Sweep time of 2218s   :o
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 09, 2013, 08:32:09 AM
Funny you noticed that.. Yep that is a 37 minute sweep. It is the most detailed sweep I ever seen.
To add a bit of color this was done by the acoustic department at Colombia college here in Chicago.

Eric
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on May 09, 2013, 09:29:43 AM
Tsk whats the cost of your capsule?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 09, 2013, 10:20:26 AM
The cost is 250 plus shipping and Paypal fees.

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on May 09, 2013, 01:38:31 PM
Thanks for posting the chart, Eric. Yes, different circuits (and likely different headbaskets, too?), so it's apples and oranges to some extent, but it does help.
There are some dips there that show in both plots, so I guess that's the room. The U47/K47 is recessed around 8kHz which is right where sibilance resides. This dip could be in the room too, but it's what you'd expect so I assume this one is for real. It is also the area where K67s have a(n extra) lift and that's obviously not the case here. Then there's a subtle peak at 10k or so and then the roll off. Quite typical for a U47, I'd say. However, there's no broad mid/high-mid bulge here, which could be caused by the room or other circumstances.
Your capsule (in the G7) shows the 7-8k dip as well, albeit a little less pronounced. And the 10k lift comes a little "sooner" (towards 9k actually), though not so soon that it would cause noticeable sibilance problems. And then yours has an extra, subtle peak beyond 10k which will add some extra air over the U47 and especially over the RK-7 capsule.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 10, 2013, 06:31:49 PM
Micaddict,

I dig the assessment. It's interesting that my capsule ended up with a bit more air, I also feal the midrange is bit more in a pleasing way as well. Almost more modern sounding but sill the Neumann sound we all know and love!

Eric
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on May 11, 2013, 03:09:52 PM
Yes, the extra bit of air is interesting, especially if you used standard 6 micron Mylar. OK, different circuits.

BTW it seems your small holes are a little smaller, if that makes sense. Assuming I'm seeing that right, was that a deliberate choice or more of a practical one due to the available "drill bit" sizes? Please excuse a possibly poor choice of words.


Henk
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 11, 2013, 09:07:08 PM
Micaddict

It's interesting you think that, the small holes are actually the exact same size as an original 47
The larger blind holes are actually bigger. The reason why is a bit of secret sauce and a big part of the dual backplate design. Any case I am pretty pleased and don't plan on changing the design..

Let me know when you want one?  ;D ;D :D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on May 12, 2013, 06:47:11 AM
LOL Believe it or not, but I was going to add the other possibility, i.e. the "large" holes being larger.
Anyway, point is there's a "bigger" difference in size. And if that works, which it obviously does, do leave it that way.

Using it in clones is one thing, but even more interestingly IMO is which of the big boys will be first to design a new microphone around it.
Only a matter of time, I say.
 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Joekkel on May 22, 2013, 06:10:24 AM
hi folks,

if i use a cm-13101 trafo with this build, am i right with these connections from the transormer to the pcb (i just looked at the pics of tskguy's post #309):

brown - pad 1
red - pad 2
yellow - pad 3
orange - pad 4
black - glink

thx and many regards
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on May 22, 2013, 06:54:27 PM
That works great for my mic! There is data sheet on the cinemags site as well.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KasperNyhus on May 30, 2013, 06:12:19 PM
YES! I finally made it...  ;D

I took a T-bone sct700 and modded it to look a bit more u47fet stylish...  :o

(https://dl.dropboxusercontent.com/u/14107936/u47fet.jpg)

(https://dl.dropboxusercontent.com/u/14107936/u47fet2.jpg)

(https://dl.dropboxusercontent.com/u/14107936/u47fet3.jpg)

Thanks Dan for another fine mic project!

I now got this little family:
(https://dl.dropboxusercontent.com/u/14107936/Neuhaus%20family.JPG)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: baadc0de on May 31, 2013, 09:47:39 AM
YES! I finally made it...  ;D
...
I now got this little family:
(https://dl.dropboxusercontent.com/u/14107936/Neuhaus%20family.JPG)

Hey mate, where did you get the 3-pin XLR insert? Care to explain a bit on making of the mount? I made two SC700 -> U47FET mics already, looking to get them to the next level :)

Also thanks and big props to Dan for making these PCBs available and supporting them.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: useme2305 on May 31, 2013, 12:04:07 PM
cool stuff! what are those u87/67 type donor bodies?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KasperNyhus on May 31, 2013, 03:16:08 PM
I bought two of these in Germany: http://www.musicstore.com/en_EN/EUR/Fame-Studio-C02-Large-Diaphragm-Microfon/art-REC0001545-000?recId=daf53a13-053c-4dba-bf77-25a842f9df7e

@baadc0de
I will take some more pictures later so you can see what I've done :)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: imo on June 08, 2013, 03:14:03 AM
Just got my build running. Sounds spectacular! NOw a D67 and the U47fet. I used the Equinox capsule and body(repurposed from an earlier mic), as well as the AMI T49. I saw a solution for mounting the XLR somewhere in the thread a couple of days ago, and cant for the life of me find it now. I have the XLR just hanging for the time being.
Is there an insert for an XLR connector that will allow me to mount it in the Equinox body? 
Ian
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: 3nity on June 08, 2013, 10:50:32 AM
Quote
NOw a D67 and the U47fet
And whats the mic you're talking about then??
this is the U47Fet thread! lol.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on June 08, 2013, 11:38:37 AM
Hehe.. I was wondering the same thing..
I think he means that he already had the D67, and now he also has the U47fet completed.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: imo on June 08, 2013, 12:18:14 PM
Sorry. Meant to say i have 2 of Dans mics(including the D67 and the fet47).
My fet47 needs an insert for the XLR to fit into the Equinox body
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on June 17, 2013, 10:18:06 PM
Keen to hear if anyone comes up with a good solution for installing a normal three pin XLR in the Equinox bodies.

I was just going to make a conversion cable for my U47fet build, with Binder connector at the mic, and XLR male at the other end.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: uffetuff on June 25, 2013, 03:11:30 PM
I'm using a Golden Age TC-1 as donor body. I thought of buying a t.bone but I had this one broken laying around so I thought it was a better (cheaper) choice. I think I'm pretty much done with the soldering of the PCBs. Just have a few questions before I proceed.

I just recently built a DU87 where I needed to measure the FET to be in a desirable value. Is that needed here too? I already put it place, but I have a bunch more.

The LC jumper, is that for Low Cut?... if not, what?

There are two jumpers for PAD. S1A and S1B, how do I use those?
The TC-1 has two switches for Pad and Low cut. I'm thinking about using those if I can figure out how the S1-things works.

I have the RK7 capsule from microphone-parts.com. I read that if you connect both front and rear to the same, you get omni. Will that work with this, or will it get weird since it's super cardioid?

Sorry for stupid questions. But I there wasn't as much useful info about this as the DU87.

Edit: deleted one question, too stupid ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on June 25, 2013, 07:02:48 PM
I'm using a Golden Age TC-1 as donor body. I thought of buying a t.bone but I had this one broken laying around so I thought it was a better (cheaper) choice. I think I'm pretty much done with the soldering of the PCBs. Just have a few questions before I proceed.

I just recently built a DU87 where I needed to measure the FET to be in a desirable value. Is that needed here too? I already put it place, but I have a bunch more.
you can select for low IDsS as the U87 does but there is no bias it is a self bias circuit

The LC jumper, is that for Low Cut?... if not, what? Yes Low cut

There are two jumpers for PAD. S1A and S1B, how do I use those?
The TC-1 has two switches for Pad and Low cut. I'm thinking about using those if I can figure out how the S1-things works.
The pad uses a dpdt switching double pole double throw,  so in order to use it you need this kind of switch or 2 separate jumper 1 on S1a and the other one in S1b those will be be in the same position for no pad and the other same position for pad if your switch is a dpdt you can trace it with the schematic
 


I have the RK7 capsule from microphone-parts.com. I read that if you connect both front and rear to the same, you get omni. Will that work with this, or will it get weird since it's super cardioid?
you can try because i did not myself where did you read that,  i really like the u47FEt for his supercardiod behavior tough

Sorry for stupid questions. But I there wasn't as much useful info about this as the DU87.

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: uffetuff on June 27, 2013, 09:48:21 AM

The pad uses a dpdt switching double pole double throw,  so in order to use it you need this kind of switch or 2 separate jumper 1 on S1a and the other one in S1b those will be be in the same position for no pad and the other same position for pad if your switch is a dpdt you can trace it with the schematic
 


Ok, but if i leave those alone with nothing on them, does that mean no pad? I think i have one of those switches from a slaughtered mic. I'll try.


you can try because i did not myself where did you read that,  i really like the u47FEt for his supercardiod behavior tough

 I don't want to make it omni full time. Just thinking abou the possibilitys to add a switch for it. I reda about it on microphone-parts.com on the info page for the RK7.
"Alternatively, wire the rear diaphragm together with the front, making your Cardioid microphone into an Omnidirectional."


Plus one more question. The isolation pin should be wired to the g-link on opposit pcb, right?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on June 30, 2013, 01:53:11 AM
Keen to hear if anyone comes up with a good solution for installing a normal three pin XLR in the Equinox bodies.

I was just going to make a conversion cable for my U47fet build, with Binder connector at the mic, and XLR male at the other end.

I used a three pin insert from an XLR cable connector I got from Jaycar. A lot of XLR connectors use the same inserts.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on June 30, 2013, 04:44:36 AM
Cheers, Enchilada!
Do you mind posting a pic of how you got the XLR insert to stay securely in the base of the Equinox body kit?
Much appreciated.
I used a three pin insert from an XLR cable connector I got from Jaycar. A lot of XLR connectors use the same inserts.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on June 30, 2013, 06:56:26 AM
Finally got around to building my one of these using the Cathedral Pipes capsule and an Alctron MK47 body. I'll pop some photos and recording samples in my build thread soon. So far, I've noticed that the proximity effect isn't particularly flattering on my voice. Although it seems a pretty detailed sound, it is a touch muddy for my liking. I've used a transformer that came out of a stock Apex 460 so that probably doesn't help. I've got a T49 on order though so we'll see if that's the problem.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on June 30, 2013, 09:33:25 AM
Cheers, Enchilada!
Do you mind posting a pic of how you got the XLR insert to stay securely in the base of the Equinox body kit?
Much appreciated.
I used a three pin insert from an XLR cable connector I got from Jaycar. A lot of XLR connectors use the same inserts.
I'm using the Alctron MK47 mic body although I was sure it used the same 7 pin connector. I'll make sure I take photos of it in my thread.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on June 30, 2013, 10:10:21 AM
Quote
Plus one more question. The isolation pin should be wired to the g-link on opposit pcb, right?

Nope the G-Link here is just an extra grounding pad not to be confused with the Gate link in the D-U87,

hope this helps,  the isolation pin on the 47FET Just supports the HZ component that connet to the FET ,

Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on June 30, 2013, 10:40:08 AM
While you're about Dan, how important is it that the 18pf is Styroflex? I've used Silver Mica because I couldn't find Styroflex. I've got some spare 22pf Styroflex, could they work?
Also, do I really need the isolation pin? I couldn't find one of those either so I just connected everything over air.
One more Q, I haven't been using my AMI U47 too much, how do you think a T47 trafo would go in this mic?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on June 30, 2013, 10:48:13 AM
While you're about Dan, how important is it that the 18pf is Styroflex? I've used Silver Mica because I couldn't find Styroflex. I've got some spare 22pf Styroflex, could they work?

they will work fine, Silver mica is a very high end capacitor might just not be the exact same coloration , the filter RC calculation or feedback will just be a tiny tad different but that's it

Also, do I really need the isolation pin? I couldn't find one of those either so I just connected everything over air.

Yes you can leave the connections in the air.

One more Q, I haven't been using my AMI U47 too much, how do you think a T47 trafo would go in this mic?
the ratio might be a bit off if we compare 6.5:1 to about 9:1 but IMO it always worth a try DIY Rules :)
might you be able to wire it in 11:1 tough  ;)






Hope this helps,
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on June 30, 2013, 11:10:28 AM
Can I? It is dual bobbin. How would I go about doing that?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: HellfireStudios on June 30, 2013, 12:23:27 PM
Can I? It is dual bobbin. How would I go about doing that?


Look up the datasheet on that particular transformer. Although, if it doesn't have taps, and the associated extra leads, you may not be able to do anything about it.

-James-
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on June 30, 2013, 05:38:07 PM
Nothing about 11:1 on the spec sheet.
http://www.tab-funkenwerk.com/id81.html
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: digdoug on July 15, 2013, 09:57:55 PM
Hi Guys,

I have done a bit more investigating on donor bodies and these seem pretty good:

Aurcyle A620, Sterling Audio ST51 both are available from amazon really cheap

i just wondered on the sizes inside for mounting the PCB's.

any info very welcome.

regards

Spence.

I have a Sterling ST-55 here that I was hoping would be large enough to accommodate the pcbs, but it's not going to happen.  Inner diameter (42mm) looks too small.  The ST-51 might be the same body without the switch cutouts. (?)

Inner diameter is 42mm.  Rails are 39 at their widest.

(http://i1294.photobucket.com/albums/b604/dougwandell/IMG_20130715_213608_zpsca216adf.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on July 21, 2013, 02:23:21 PM
I did post the pcb dimension on the site , the pcb were specicifically made for the GT-2B alias thomannsct-700 and the like,

Might also Chunger from the groupdiy might have some more of those,

http://www.groupdiy.com/index.php?topic=50015.0

or

http://www.thomann.de/gb/the_tbone_sct700_roehrenmikrofon.htm

other mxl fit the bill as i can recall the mxl4000 Large like a glove ,

here is a link on it ,

http://www.mxlmics.com/microphones/900-series/4000XL/

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Joekkel on July 27, 2013, 12:08:29 PM
d-u47fet finished! beautiful sound!! thanks poctop, this is my third mic from you and it's killer like the other two!!

http://www.facebook.com/photo.php?fbid=10201801775952918&l=eec8c3b02e (http://www.facebook.com/photo.php?fbid=10201801775952918&l=eec8c3b02e)
http://www.facebook.com/photo.php?fbid=10201801776632935&l=97ab2ac92f (http://www.facebook.com/photo.php?fbid=10201801776632935&l=97ab2ac92f)
http://www.facebook.com/photo.php?fbid=10201801776152923&l=2136252469 (http://www.facebook.com/photo.php?fbid=10201801776152923&l=2136252469)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on July 27, 2013, 12:16:05 PM
Quote
d-u47fet finished! beautiful sound!! thanks poctop, this is my third mic from you and it's killer like the other two!!

http://www.facebook.com/photo.php?fbid=10201801775952918&l=eec8c3b02e (http://www.facebook.com/photo.php?fbid=10201801775952918&l=eec8c3b02e)
http://www.facebook.com/photo.php?fbid=10201801776632935&l=97ab2ac92f (http://www.facebook.com/photo.php?fbid=10201801776632935&l=97ab2ac92f)
http://www.facebook.com/photo.php?fbid=10201801776152923&l=2136252469 (http://www.facebook.com/photo.php?fbid=10201801776152923&l=2136252469)

Thanks For the kind Word , always appreciate the feedback.
I tried to acess the photo but i could not , might just be some delay in the server since it is freshly uploaded.   :)
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Joekkel on July 29, 2013, 05:10:18 PM
so, the pics should work now  8)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on July 29, 2013, 05:56:43 PM
Did you use Cinemag reprodution of the 47FET ?

how did you like it ,  :)

Thanks for the updates,

Best,
DAn,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Joekkel on August 01, 2013, 01:55:04 PM
yeah, the cinemag-transformer. i like it quite a lot. haven't really used it yet tough. i did a little shootout today between the d-u87, 67 and 47fet. the 47fet was the brightest in the very highs and the 67 the smoothest, didn't expect that. but all sound damn good. the 47fet has a nice presence-boost and less lower mids than the 87 and 67. need to shoot'em out against the real deal and will soon :)

if the lc-jumper is in, lc is in on the 47fet, right? i heard the 47fet is a bass-strong mic, but on voice it seems thinner than the other 2 mics, since it has less lower mids. could be the positioning as well, never easy to place big mics close enough...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on August 01, 2013, 01:57:15 PM
Quote
if the lc-jumper is in, lc is in on the 47fet, right?
Correct,


The Overall sound will also depends on the capsule you have in there  ;)
Best,
Dan, :)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Joekkel on August 01, 2013, 02:19:16 PM
yeah, capsules are mid to lowcost.

-beesneez phelicity k47 in the 47fet
-peluso k87 in the 87
-chinese k67 in the 67 (from chungers syt-5)

will upgrade capsules, if the comparison to the real neumanns isn't too favorable. but i have high expectations ;) and i think the d-u67 sounds perfectly smooth, no need for a smoother capsule. perhaps a neumann would sound a little clearer in the mids, we'll see
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on August 01, 2013, 05:11:10 PM
Quote
i think the d-u67 sounds perfectly smooth, no need for a smoother capsule.

That says something about the relatively cheap capsule and it says something about the clever circuit.
Hard to beat a 67.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Luax on August 11, 2013, 07:47:31 AM
Hi Guys,

I'm about to enter the final stage of my build: installing the M7 capsule.
But before I screw anything up(it's my first mic build), I wan't to double check some things.
The capsule is a Thiersch M7 with two wires on the back/front.
I've read many of the posts on the board, but I'd like to clear-up the following with regards to the wiring:

-If I solder one wire to front(pcb marking) and other to back(pcb marking) I get super cardioid?
-If I solder both wires to front and none to back (with a switch between one of the wires) I could make a cardioid/omni ?
-In both cases do I need to attach a third wire from the capsule mount to ground?

Hope you can confirm/correct my questions. I'll post pictures as soon as the build is finished.

All the best,

Lucas
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on August 11, 2013, 11:22:29 AM
Hi Guys,

I'm about to enter the final stage of my build: installing the M7 capsule.
But before I screw anything up(it's my first mic build), I wan't to double check some things.
The capsule is a Thiersch M7 with two wires on the back/front.
I've read many of the posts on the board, but I'd like to clear-up the following with regards to the wiring:

the wiring of this mic capsule is that the backplate (  metal middle portion)  goes to ground via the BCK pad there 2 pads but only one is labeled BCK and this one shows continuity trough  the large pad F and the front capsule goes to the floating connection of R1 and C1 , there is no circuitry for polarisation of the back capsule as it is a FET47 and the resulting pattern is the one that make the U47FET know for that is the super-cardiod

-If I solder one wire to front(pcb marking) and other to back(pcb marking) I get super cardioid?
-If I solder both wires to front and none to back (with a switch between one of the wires) I could make a cardioid/omni ?
-In both cases do I need to attach a third wire from the capsule mount to ground?

the third wire left will be the one from the back capsule diaphragme and this one should be isolated wih a shrink wrap and do no connect

Hope you can confirm/correct my questions. I'll post pictures as soon as the build is finished.

looking forward to see picture of your build ,

Also make a special atention for the capsule screw mount not to touch the headbasket you may want to move them or use the side one , as the capsule his sitting high in the headbasket ,

All the best,

Lucas

It is always of good pratice to always have a copy of the original schemactic while doing the Work,
hope this helps,

Best,
DAn,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Steph.B on August 28, 2013, 07:19:32 AM
Hi folks,

Just a few words to say that I ordered a pair of CM-13101 transformers from Cinemag and I was amazed by the customer service !

In the minutes I've sent my mail for an inquiry, David Geren replied back giving me all the purchasing infos and the invoice was on my paypal account just after my next confirmation mail.

David is actually the one who designed this transformer. He is also the president of Cinemag.

I wish all companies were this nice and responsive !  ;D

Anyways, thanks to David from Cinemag for the care he has for his customers and the great products he gives life to !  8)

Cheers,
Stéphane.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: yoons on September 11, 2013, 01:35:43 AM
Hello.

I almost finished my 2 D-U47. Just the transfo and capsule to connect (Cinemag cm-13101 and Beesneez K7). Should be done before the end of the day.
Thanks Dany for sharing those great projects ;)
Here are few pics :

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261987)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261988)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261989)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261990)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261991)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261992)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261993)

Dany=> I try to order M49 square pcb version but they aren't availlable. Do you plan to make new batch?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on September 12, 2013, 11:04:20 AM
Hello.

I almost finished my 2 D-U47. Just the transfo and capsule to connect (Cinemag cm-13101 and Beesneez K7). Should be done before the end of the day.
Thanks Dany for sharing those great projects ;)
Here are few pics :

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261987)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261988)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261989)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261990)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261991)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261992)

(http://img.audiofanzine.com/image.php?lang=fr&identifier=image&size=normal&module=user&userPhoto_id=261993)

Dany=> I try to order M49 square pcb version but they aren't availlable. Do you plan to make new batch?

Thanks for your posts  :) ,  very neat build  8)  for optimal results make sure the body of C1 is not touching the pcb.
one note on the backplate connection on the pad beside the label bck is actually connected to ground this is the one you will need to connect the back plate  ;)
Let me know how you like em once you get those new born fired up  :)

PMed you about the M49 square kit ,

Thanks Again, appreciate it ,
Best,
dAn,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: yoons on September 13, 2013, 06:09:12 AM
Here are few samples :

https://www.dropbox.com/s/jzfd3zprd7baaed/B%26C.mp3 (https://www.dropbox.com/s/jzfd3zprd7baaed/B%26C.mp3)
https://www.dropbox.com/s/msk3qcmatdjk3bq/Falling%20Star.mp3 (https://www.dropbox.com/s/msk3qcmatdjk3bq/Falling%20Star.mp3)

Here is the chain used : D-U47 => GML 8302=> Antelope Orion 32
No eq/comp/fx.

To soon to make solid comment, but at the moment I love what I hear. Real vintage feel with soft high and great mids/low-mids.
We did a short selection before starting rec. We choose the DU47 over U87 (first generation, not the AI) and Audiotechnica AT4060.
U87 had to much highs for this voice and AT4060 was great but too much ssss.
I can post thoose samples too if someone is intersted.

More info from Dan about C1 :

Quote
when you say that it must not touch the pcb you mean 1mm is enough or should it be at good distance?
Cause I haven't noticed problem in sound, how does it translate?

Best,
Younes
barely to make sure air becomes the isolation 1mm is plenty enough,
Best,
DAn,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on September 14, 2013, 11:27:26 AM
Here are few samples :

https://www.dropbox.com/s/jzfd3zprd7baaed/B%26C.mp3 (https://www.dropbox.com/s/jzfd3zprd7baaed/B%26C.mp3)
https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281993ed3.mp3 (https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281993ed3.mp3)

Here is the chain used : D-U47 => GML 8302=> Antelope Orion 32
No eq/comp/fx.

To soon to make solid comment, but at the moment I love what I hear. Real vintage feel with soft high and great mids/low-mids.
We did a short selection before starting rec. We choose the DU47 over U87 (first generation, not the AI) and Audiotechnica AT4060.
U87 had to much highs for this voice and AT4060 was great but too much ssss.
I can post thoose samples too if someone is intersted.

More info from Dan about C1 :

Quote
when you say that it must not touch the pcb you mean 1mm is enough or should it be at good distance?
Cause I haven't noticed problem in sound, how does it translate?

Best,
Younes
barely to make sure air becomes the isolation 1mm is plenty enough,
Best,
DAn,

Thanks Younes for this post , I am big Jazz Fan so i really appreciate it,  glad you happy with the results,
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: wir68 on September 24, 2013, 05:05:53 AM
Good morning
I'm in France and new on this forum.
What transformer for U47FET with R47 capsule : Cinemag 2480, 1303 Sowter, AMI T49 ??
Can you help me ?
The micro is for voice and guitare also.
Thank you for the answer
Pierre
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on September 25, 2013, 11:51:14 AM
Good morning
I'm in France and new on this forum.
What transformer for U47FET with R47 capsule : Cinemag 2480, 1303 Sowter, AMI T49 ??
Can you help me ?
The micro is for voice and guitare also.
Thank you for the answer
Pierre

Wich mic body will you be using ,.
these are all excellent transformer, the most suitable would be the AMIT49 or the cinemag 13101 specifically design as a replica of the original by Dave at cinemag when i had sent him an original to play with for a while.  :)

http://cinemag.biz/mic_output/mic_output.php CM13101

Best,
D


Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: wir68 on September 25, 2013, 04:53:03 PM
Quote
Wich mic body will you be using ,.
I'm using the T bone SCT700
Pierre
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Melodeath00 on September 26, 2013, 01:47:06 PM
I noticed Cinemag describes their CM13101 as having less distortion than the FET47 transformer yet "a similar THD at Fixed Frequency curve shape." Any idea what that means? And can they customize it to have more distortion? They mention there are different lamination choices based on the customer's preference.

Also, the ratio is 9.1:1, but AMI's T47 is 6.5:1. Odd.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on September 26, 2013, 02:11:51 PM
I noticed Cinemag describes their CM13101 as having less distortion than the FET47 transformer yet "a similar THD at Fixed Frequency curve shape." Any idea what that means? And can they customize it to have more distortion? They mention there are different lamination choices based on the customer's preference.

Also, the ratio is 9.1:1, but AMI's T47 is 6.5:1. Odd.

The AMI T47 is for tube 47 wich is 6.5:1 the AMI T49 is 9:1 for this build,

you sure can ask dave at cinemag he is very receptive .  :)  PS: somtimes distorsion is better and sometimes not  ;)

Best,
Dan
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Potikinawah on October 10, 2013, 06:12:02 AM
Hi Dan,

Just had a question. Is the D-U47 suitable for a multi-pattern U47fet (8-cardio-omni) ? Just need a good microphone capsule and (the difficult stuff) the right body with a 3-position switch on ?

Thanks,
Yoh
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 10, 2013, 10:05:18 AM
Hi Dan,

Just had a question. Is the D-U47 suitable for a multi-pattern U47fet (8-cardio-omni) ? Just need a good microphone capsule and (the difficult stuff) the right body with a 3-position switch on ?

Thanks,
Yoh

the D-U47 FET just like the originals beast is a supercardiod only microphone ,  there is a pad and a low cut but the pad require a dpdt switching device but as usual you can use the internal jumper setting to use them IMO once they are set i use it pretty much on everything without even thinking about it .

Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Leer on October 31, 2013, 11:53:21 AM
Does the Sowter transformer fit inside the Alctron-style mic?

Thanks, Peter.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 31, 2013, 01:57:43 PM
Does the Sowter transformer fit inside the Alctron-style mic?

Thanks, Peter.

do you have the precise dimension of the sowter transformer i could measure at home,

Let me know ,
Best,
dAN,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Leer on October 31, 2013, 07:16:39 PM
It's their 1303, cylinder shape
Quote
Ratio 9:1. Sowter designed transformer similar to Neumann U1 with a single secondary winding. Internal electrostatic shield to ensure good comon mode rejection.
Mumetal can with colour coded leads 34 mm dia. x 24 high.
from the sowter homepage
Thanks,
Leer.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 31, 2013, 07:24:50 PM
It's their 1303, cylinder shape
Quote
Ratio 9:1. Sowter designed transformer similar to Neumann U1 with a single secondary winding. Internal electrostatic shield to ensure good comon mode rejection.
Mumetal can with colour coded leads 34 mm dia. x 24 high.
from the sowter homepage
Thanks,
Leer.

I measured it on the first page you see a cinemag 2480 there for testing ,
so the space remaining after the boards are 38mm high and diameter of the shell,
if it is a gt2B style mic then you have 38mm*50mm left ,
plenty of room to accomodate about any transformer including the T49 or the sowter,
Best,
DAn
 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Leer on October 31, 2013, 08:17:20 PM
Thanks, looking forward to order some PCB's soon,
Leer.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: NorthernLight on December 17, 2013, 08:05:21 AM
Probably a simple question; I'm examining the mouser basket for this project, and see a lot of different brand and type resistors. I have a big stock of 1/4 watt 1% metal film resistors in values up to 10M, can I use these anywhere a 1/4 watt resistor is specified, or are there places where Carbon or "Think-film", or specified PPM of the resistors are critical?

Also in the basket are 3x 2N3819, 10x BC547B and 10x BC557B transistors, while only 1x 2N3819, 2x BC557B and 4x BC547B go on the PCB. I have not read anything about matching or testing for special properties, why the extra transistors?

Thanks,  Alex.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on December 19, 2013, 04:08:19 PM
Probably a simple question; I'm examining the mouser basket for this project, and see a lot of different brand and type resistors. I have a big stock of 1/4 watt 1% metal film resistors in values up to 10M, can I use these anywhere a 1/4 watt resistor is specified, or are there places where Carbon or "Think-film", or specified PPM of the resistors are critical?

Also in the basket are 3x 2N3819, 10x BC547B and 10x BC557B transistors,

some spares are always nice to have as long as the fairchild is in production  ;), and you can select for best HFE if you need to
for the FET selected on the best IDSS if you need to.

while only 1x 2N3819, 2x BC557B and 4x BC547B go on the PCB. I have not read anything about matching or testing for special properties, why the extra transistors?

some spares are always nice to have as long as the fairchild is in production  ;), and you can select for best HFE if you need to
for the FET selected on the best IDSS if you need to.

hope this helps,
Dan,


Thanks,  Alex.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on February 06, 2014, 04:55:36 AM
In case Eric (or Dany) is too modest to post this himself.

Pour a cup and watch this, folks.

http://www.youtube.com/watch?v=Kbd0TnvL_gA#t=18 (http://www.youtube.com/watch?v=Kbd0TnvL_gA#t=18)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on February 07, 2014, 05:56:33 AM
Oh, and the impatient can start at the 16.50 mark.
Do realize all the big boys were covered before that.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Winetree on February 07, 2014, 04:56:16 PM
I had gotten them in the past,
but Just Radios doesn't list 18pf/630v polystyrene caps,
just 15pf/630 or 20pf/630.
Can I use one of these?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 07, 2014, 05:05:04 PM
I had gotten them in the past,
but Just Radios doesn't list 18pf/630v polystyrene caps,
just 15pf/630 or 20pf/630.
Can I use one of these?

I do supply the closest value now it is 20pf
 best you can do indeed, tolerance is always in our favor  ;)
dD
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ArKay99 on February 09, 2014, 03:14:22 PM
I'm a recent sign-up and this is my first post.  :) This article caught my eye because I have an AT2035 (audio-technica) that frankly sounds pretty flat out of the box. I know the pcb's won't fit, but I can construct pcb's on my own that I could make fit, simply because of the simplicity, parts count, and real estate of the parts involved. It would be tight, but I believe I could do it if careful by making two round pcb's. This is the 1st part of my question... I'm 'curious' as to the 'real world' part number of the 8280800022 fet (is that the real world part number or a Neuman in house one), even though it would prolly be next to impossible to find one to purchase. I think that question was asked in the post but I didn't find an answer... The next part of my question regards the transformer. The 47FET transformer is out of the question as far as size goes, as is the Sowter 1303. I could shoehorn a T13 or a 2480 in there. The 2480, I understand was used in the last few pictures of the build documentation, and from the specs of the Sowter transformer it is pretty close to a T13. However, I have not been able to find the inductance of the FET47, so I have reference as to the inductance as it relates to the T13, so my question here is, can I use a T13 and expect desirable results? If so, what would I be trading off? Would I be able to alter the values of say C1 or C10 to reduce any non-linearities that might be introduced by using this transformer. Finally, the AT2035 has 2 switches at the bottom of the body. If I'm creating two boards to hold the electronics I can create a board to hold the switches...what I'm concerned about is the noise pickup due to running 8 wires 2 inches inside the mic body. I can keep them out and just use the jumpers or hard-wire the conns using a s couple of close pads on the pcb. Sorry for the long post as I wanted to enumerate my concern for shooting myself in the foot before I pull the gun out... I can do the pcb layout easily as that's what I'm currently doing for a living (in addition to being a musician), and because of that I can get pcb's in small quantities 'dirt cheap' relatively'. What I am painfully aware of is the old adage 'a little knowledge is dangerous'. The whole point being, that if this experiment doesn't work out, I'd only be out a couple of pcb's and a T13 or other transformer, as I would just buy a donor body and finish the design there, but I would like to try the AT body first.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on February 09, 2014, 03:28:18 PM
I'm a recent sign-up and this is my first post.  :) This article caught my eye because I have an AT2035 (audio-technica) that frankly sounds pretty flat out of the box. I know the pcb's won't fit, but I can construct pcb's on my own that I could make fit, simply because of the simplicity, parts count, and real estate of the parts involved. It would be tight, but I believe I could do it if careful by making two round pcb's. This is the 1st part of my question... I'm 'curious' as to the 'real world' part number of the 8280800022 fet (is that the real world part number or a Neuman in house one), even though it would prolly be next to impossible to find one to purchase. I think that question was asked in the post but I didn't find an answer... The next part of my question regards the transformer. The 47FET transformer is out of the question as far as size goes, as is the Sowter 1303. I could shoehorn a T13 or a 2480 in there. The 2480, I understand was used in the last few pictures of the build documentation, and from the specs of the Sowter transformer it is pretty close to a T13. However, I have not been able to find the inductance of the FET47, so I have reference as to the inductance as it relates to the T13, so my question here is, can I use a T13 and expect desirable results? If so, what would I be trading off? Would I be able to alter the values of say C1 or C10 to reduce any non-linearities that might be introduced by using this transformer. Finally, the AT2035 has 2 switches at the bottom of the body. If I'm creating two boards to hold the electronics I can create a board to hold the switches...what I'm concerned about is the noise pickup due to running 8 wires 2 inches inside the mic body. I can keep them out and just use the jumpers or hard-wire the conns using a s couple of close pads on the pcb. Sorry for the long post as I wanted to enumerate my concern for shooting myself in the foot before I pull the gun out... I can do the pcb layout easily as that's what I'm currently doing for a living (in addition to being a musician), and because of that I can get pcb's in small quantities 'dirt cheap' relatively'. What I am painfully aware of is the old adage 'a little knowledge is dangerous'. The whole point being, that if this experiment doesn't work out, I'd only be out a couple of pcb's and a T13 or other transformer, as I would just buy a donor body and finish the design there, but I would like to try the AT body first.

Welcome! 

One tip:
Divide your posts into (logical) paragraphs and more people will read them.  ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on February 09, 2014, 03:59:10 PM
Yes for sure!! Most of us here have add and I spaced out after the audio techn........:)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 09, 2014, 04:00:14 PM
Do You mean Something Like This  ;)   A version i have but never used it yet , I am preparing this one for a customer,  it has been made for the U47 3 railing body like the AMI and/or IOaudio, So it is round , as you notice I also added a O-ring supension set that suppose to work in my favor.  it is indeed a lot of fun ,

I might have only one Left but not sure, Let me know if interested,

D-47FET    3 Railing system (AMI-IOaudio) microphone body type.  i am working with Oliver to have the tube Cut , i am expecting a prototype soon, so will see,

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a067ed.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a06819.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a06829.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0683a.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a0684b.jpg)

(https://dl.dropboxusercontent.com/u/43869772/U47/U47FET%20Round/CAM00163.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d028199401c.jpg)

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ArKay99 on February 09, 2014, 07:41:38 PM
micaddict... sorry, didn't mean to rewrite the Magna Carta, I started describing what I wanted to do and tried to justify my whim... I'll try to follow your advice in the future.

poctop: yes that is the idea, although I am inferring that assembly was created for a u47 body. My AT has an internal diameter of 44.5mm and a height of 38mm. If those dims are compatible I'd be very interested as it would save me a ton of work. If the diameter is a fit, but the height out of spec, would using a transfo like a T13 work?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Jim50hertz on February 10, 2014, 07:08:01 AM
I'm fortunate enough to have one of these in the works (thanks Dany! ;)).  How easy would it be to  implement pattern switching?

Apologies if this is something that has been gone over.

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 11, 2014, 08:23:43 AM
I'm fortunate enough to have one of these in the works (thanks Dany! ;)).  How easy would it be to  implement pattern switching?

Apologies if this is something that has been gone over.

the original design of the U47FET has been made to render this mic very special since it has only one pattern available wich is in this case Supercardiod as opposed to cardiod resulting in a very nice flatting transient response and very tight pattern something like in the middle of figure 8 and cardiod to my ears, implementing a patttern switching would be doable-DIYable by adding a cross polarisation scheme and feedback-filtering as simple as the M49 pattern scheme for example and of course a switching for  both side,  but i would alter this solely purpose of this mic,  the M49 Style mic would be something to reference to.
as the  ''lengend''  ;)  says the U47Fet original capsule were the K49 style that did not meet the matching on both side so Neumann would take those capsule and put them in the U47Fet making it this very special animal in that time , so very different minding as putting a one sided gold depostion diaphrgame as in the TLM49 

Best,  ;)
DAn
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: muffy1975 on March 04, 2014, 04:58:44 PM
Guys,

if i wish to remove the 10db pad and the low cut filter, which parts do i not stuff?


many thanks in advance

Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: MatthisD on March 04, 2014, 05:25:07 PM
Regarding the pad, do you already have the parts listed in the BOM? if not you can substitute the 2 capacitors and 2 resistors for one of each by choosing values to emulate the unpadded position and jumper across the unstuffed component pads which would mean omitting R2,C2 and installing a bridge across one or the other.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: muffy1975 on March 08, 2014, 06:07:27 PM
Hey thanks for that.


I have the 100m and the 200m and the 20m all connected together and i have the 33pf and 18pf all connected together too. Seems to be working out.


Cheers


Michael.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: MatthisD on March 09, 2014, 03:07:32 AM
No problem, you have five components there where two would do the job but you have already paid for them so no need to replace.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Jim50hertz on March 09, 2014, 09:45:35 AM
Got mine up and running this morning, Beesneez K7 and Cinemag Trafo.

Sounds great! I can see why these are so favoured on bass amps, sounds great on my B15.  Great pickup :)

I'm very happy, thanks for this Dany  8)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 17, 2014, 08:44:21 AM
Thanks To my Brother , I should have some 47Fets PCB available soon,
Best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 24, 2014, 08:24:08 AM
New Run of this are on their way ,
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 28, 2014, 11:45:38 AM
Finally Received a Short U47 FET Prototype Body From Oliver At AMI ,

i have sent the mic to higher authorities to get it evaluated, So Far So Good,

I should hear back soon,

Best,
DAn,
 
Oliver Archut U47Fet Short Body Prototype

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a069a3.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a069b4.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a069c1.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a069d3.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a069e4.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a06a0f.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a06a21.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a06a32.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00176.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d02819940ad.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Melodeath00 on March 28, 2014, 01:25:14 PM
Awesome! Probably a fairly expensive body, though :(
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 28, 2014, 01:29:35 PM
Awesome! Probably a fairly expensive body, though :(

Actually Have no idea :)
DdD
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Steph.B on March 28, 2014, 08:09:34 PM
Holy cow this sure looks nice !  8)

Wonder if the body would sell separately.

It will be a hard time to choose between this one and the GT-2B V.2 Chunger is getting made...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Melodeath00 on March 28, 2014, 09:24:07 PM
Dany, which tranny is in that prototype?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 29, 2014, 10:07:30 AM
Holy cow this sure looks nice !  8)

Wonder if the body would sell separately.

It will be a hard time to choose between this one and the GT-2B V.2 Chunger is getting made...

I am sure Both will mic body will be awesome knowing that Chunger has so much attention to details,
the AMI one is sort of a long shot , i have no deadline for those neither a price and the volume will be probably pretty limited for a starter. My Bet is that Chunger will have a Nice stock of the Gt-2B before this one shows up. this is I guess just a Primer of somthing coming but I really have no deadline as everyone knows that Oliver is a very Busy Man,


The transfo I have used is the T47 from Oliver ,

Best,
dAN,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 03, 2014, 09:32:09 AM
I should have them as of tommorow ,
Best,  :)
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 03, 2014, 08:48:32 PM
they Arrived,
Best,
DAN ,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Leer on April 16, 2014, 06:00:49 PM
Hi Dany.
How do I pick the right transistors? Highest possible HFE or?
And how about the trim resistor?
Best Regards,
Peter.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 17, 2014, 08:40:07 AM
Hi Dany.
How do I pick the right transistors? Highest possible HFE or?
And how about the trim resistor?
Best Regards,
Peter.

Pick the highest HFE. but in reality according to the spec sheet of the transistor use in the bom they are in a class where the hfe should be meet so it is not a worry,  you can skip the trimpot and replace with the proper resistor also in the bom ,
look on page 1 of this thread and you will find explanation regarding this,
Best,
dAN, <
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: dandeurloo on April 27, 2014, 02:08:39 PM
Has anyone been able to confirm the polarity is correct on these when the AMI transformer is wired as below?  I have mine wired this way and I have the OUTPUT pads to XLR wired Pin 1 to pin 1, pin 2 to Pin2, Pin 3 to pin3. 

In headphones it seems to be out of phase with other known mics.  I would love to know if it AMI is correct or not?

AMI Transformer wired:
D to pad 3
C to pad 4
A to pad 1
B to pad 2
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 27, 2014, 02:16:24 PM
Has anyone been able to confirm the polarity is correct on these when the AMI transformer is wired as below?  I have mine wired this way and I have the OUTPUT pads to XLR wired Pin 1 to pin 1, pin 2 to Pin2, Pin 3 to pin3. 

In headphones it seems to be out of phase with other known mics.  I would love to know if it AMI is correct or not?

AMI Transformer wired:
D to pad 3
C to pad 4
A to pad 1
B to pad 2

According to these this is correct,
it should be in phase,  maybe you have made a mistake with the xlr connector and not the transfo, double check to make sure,
hope this helps,


Best,
DAn,

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a06c6e.jpg)


(https://dl.dropboxusercontent.com/u/43869772/FET%20TRansfo%20connection.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d028199418a.jpg)

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Graph on April 28, 2014, 08:16:36 PM
Hi, i am planning to make a pair of u47 fet :) i saw that MXL 550 may work in the build, did anyone test if it fits right? Or is it there any other cheap donor mic?

Alctrons are not in stock right now :(

Thanks!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on May 05, 2014, 06:09:02 AM
Does the JFet IDSS matter with this circuit like the U87 as far as Gain and headroom is concerned? I have the following 2n3819 IDSS's 6.80ma, 7.13ma, 7.21ma, 8.29ma and 8.61 ma. What would be the ideal FET IDSS be?

Thanks  :)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on May 25, 2014, 12:49:13 PM
Hi Guys!

Just chiming in to report another D-U47FET-build in progress!  :)

This is yet another well designed set of PCBs from poctop, so the build is very fun and straight forward.
I opted for the R2 and bias bridge combination to make things easy..

The plan is to use the GT-2B donor body from Chunger when they arrive.
I am thinking of using the Cinemag 13101 transformer as I have read good things about it, and it seems designed specifically for the U47FET.

Anyone here who has tried the T49 and wants to add something about it in U47FET applications?
The price is virtually the same, though I have not read som much regarding the T49 and I don't know if it is specifically made for the U47FET.
Feel free to let me know your thoughts!  ;)

Best,
Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on May 30, 2014, 09:59:19 AM
Hi guys. I finished my build. I used the RK47 capsule, Styrene caps and Cinemag 13101. In the first test it sounded really thin and the sibilance was terrible. So I went through my work and everything seemed to be correct. I decided to change out the 20pF styrene cap (supplied by Danny) with a 10pF Mica Mouser #598-cd15cd100d03f. The difference was night and day. The Mid'ss Mid/Hi's and Hi's all fell into place. I guess it is possible that the styrene was faulty but, I could not test it as I don't have a capacitance meter. I did wonder if the RK47 was brighter than the original capsule when I ordered it as the RK47 only has a 3 microns rather than the original K47 being 6 microns.

I also noticed this mics has a fair whack more output than my 87 clone. Has anyone else noticed this?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 30, 2014, 05:12:47 PM
Hi guys. I finished my build. I used the RK47 capsule, Styrene caps and Cinemag 13101. In the first test it sounded really thin and the sibilance was terrible. So I went through my work and everything seemed to be correct. I decided to change out the 20pF styrene cap (supplied by Danny) with a 10pF Mica Mouser #598-cd15cd100d03f. The difference was night and day. The Mid'ss Mid/Hi's and Hi's all fell into place. I guess it is possible that the styrene was faulty but, I could not test it as I don't have a capacitance meter. I did wonder if the RK47 was brighter than the original capsule when I ordered it as the RK47 only has a 3 microns rather than the original K47 being 6 microns.

I also noticed this mics has a fair whack more output than my 87 clone. Has anyone else noticed this?

Polystyrene caps can go bad really quick if overheated special care with those,
as far as the gain goes , it should not be really really more hotter than the U87i, if the impedance is not correct it will have more gain and pretty bright ,
I would defo check the transformer wiring to make sure you did not put it in reverse , have seen it before, 
this will make it bad,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on May 30, 2014, 11:35:38 PM
Cool thanks mate. I'll check over the wiring of the trans.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on June 01, 2014, 06:06:56 AM
Hmmm okay It checked through the wiring of the Trans and all is correct. Ohms reading are correct and the phaseing is correct. Any other reason why the mic sounds thin with hot gain? 

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on June 01, 2014, 09:43:32 AM
Hmmm okay It checked through the wiring of the Trans and all is correct. Ohms reading are correct and the phaseing is correct. Any other reason why the mic sounds thin with hot gain?

a transistor badly oriented or a build error,
Best,
DAn
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on June 01, 2014, 04:23:22 PM
Check the orientation on T4.
It is easy to assume it should be aligned as the others and overlook that it is actually turned the other way round.
I almost made myself unhappy with that one..

Good luck and let us know your progress!

Cheers,
Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on June 02, 2014, 05:39:54 AM
I have checked all components. Transistors are in the correct orientation, Caps are correct value components and in the correct orientation. Resistors are correct values (I measure each before stuffing). Have checked my work over and over. This is not my first DIY. IT's maybe the 30th.

My suspicions are the RK-47 I have is a piece of sh*t.
In any case I'll just chuck it in the cupboard and use my D87 instead. It has come up fantastic.  Thanks
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on June 02, 2014, 06:08:34 AM
My suspicions are the RK-47 I have is a piece of sh*t.
That's what I thought.....

Udo.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kidvybes on June 02, 2014, 02:21:10 PM
...I also find the 3-micron RK-47 rather bright...the microphone-parts RK-7 is not quite so bright and uses 6-micron mylar...

...but here's the interesting thing I found...the 35mm center-terminated capsule that Chunger sells as his "K67" for $32 bears more than a coincidental similarity to the Peluso CEK-47, below (same metalwork, 6-micron mylar and even the wiring is the identical colors)...if I remember correctly Chunger put it in one of his 47-style builds, then he lent it to a studio for testing, and they expressed a desire to keep it...that 35mm K67 does not display the typical high-end bump associated with classic K67 and K87 capsules...as a matter of fact, Dave Thomas uses that same capsule as the stock option on his CM-47 tube mic...

...just thought I'd put that out there...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Matador on June 02, 2014, 03:25:26 PM
...I also find the 3-micron RK-47 rather bright...the microphone-parts RK-7 is not quite so bright and uses 6-micron mylar...

...but here's the interesting thing I found...the 35mm center-terminated capsule that Chunger sells as his "K67" for $32 bears more than a coincidental similarity to the Peluso CEK-47, below (same metalwork, 6-micron mylar and even the wiring is the identical colors)...if I remember correctly Chunger put it in one of his 47-style builds, then he lent it to a studio for testing, and they expressed a desire to keep it...that 35mm K67 does not display the typical high-end bump associated with classic K67 and K87 capsules...as a matter of fact, Dave Thomas uses that same capsule as the stock option on his CM-47 tube mic...

...just thought I'd put that out there...

Recordinghacks.com says that "The CEK-47 uses imported metalwork; diaphragms of German Mylar are fitted and tuned in the US."...do you think the brass-work is identical and simply the diaphragms are different?  Or are you thinking that Peluso is selling the Chinese K67 as-is?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kidvybes on June 02, 2014, 05:03:15 PM
Recordinghacks.com says that "The CEK-47 uses imported metalwork; diaphragms of German Mylar are fitted and tuned in the US."...do you think the brass-work is identical and simply the diaphragms are different?  Or are you thinking that Peluso is selling the Chinese K67 as-is?

...Dave Thomas has on more than one occasion stated that his K67 capsule is the result of John Peluso and Verner Ruvalds original designs as manufactured in China (same as Chunger's capsule)...Peluso/Ruvalds article linked below...

...I can't comment on what Peluso actually does in terms of skinning, but the metalwork/screwheads are clearly the same as well as the wire colors and connections...the subject about skinning came into question when it was noted that the capsules had red lock-tight on all of the wire terminations (as they are shipped from China) and grey lock-tight on the backplate screws (see pic below)...why 2 colors of lock-tight?...was Peluso simply adding the grey lock-tight after manufacturing?...when you consider the distribution of Peluso products worldwide, could he be skinning all of these capsules on his workbench himself?...draw your own conclusions...

http://www.npr.org/templates/story/story.php?storyId=89705610
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Matador on June 02, 2014, 05:17:08 PM
Yup, makes sense.

I'm curious why people are running away from talking about "Chinese brasswork" in their products:  the pieces I have seen in samples coming from China are really top-notch and of remarkable quality (especially for the price)...

Nothing to be ashamed of in my opinion!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on June 03, 2014, 04:06:51 AM
Yeah I suspected it was the capsule. I might buy chungers 67 cap and give it a whirl.  I'll be back with my findings.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Andydrum82 on June 24, 2014, 06:59:33 AM
Hey guys this is my first post & first time building a DIY mircophone. So I have populated the PCB's & have wired in the XLR connector. I am nervous about wiring the capsule to the board as it has 2 wires for the backplate & 1 on the side. Where do these go? Do they connector to one of the molex pins? Also the Gound hole near the XLR holes is that for the transformer ? I am using the Cinemag 13101.   
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: wave on June 24, 2014, 09:10:01 AM
Hey guys this is my first post & first time building a DIY mircophone. So I have populated the PCB's & have wired in the XLR connector. I am nervous about wiring the capsule to the board as it has 2 wires for the backplate & 1 on the side. Where do these go? Do they connector to one of the molex pins? Also the Gound hole near the XLR holes is that for the transformer ? I am using the Cinemag 13101.

Have you looked through the build up pics that Dany posted in the 1st page of this thread?

-Dave
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Andydrum82 on June 24, 2014, 07:50:42 PM
All sorted out now. Just a dumb moment on my behalf
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on July 03, 2014, 08:38:56 AM
Hi Guys, Finally I got my hands on another capsule. It was supposed to be for my M49B build, but it ain't coming out of this mic in a hurry. I'll have to order another.

Sound files between the RK47 capsule and Cathedral Pipes (Dale) M7.
No processing apart from gain matching.
No creamy pre just recorded through an A&H QU24 console into Cubase 7

Love the Dale M7! So smooth

Also the test confirms my thoughts, the RK-47 (well the one I bought anyway) is junk.



RK-47
https://www.dropbox.com/l/Lqt3IhDnIgmfLLQ3K2NAAq? (https://www.dropbox.com/l/Lqt3IhDnIgmfLLQ3K2NAAq?)

M7
https://www.dropbox.com/l/AQWyj6DptojEDj53JKAoZn? (https://www.dropbox.com/l/AQWyj6DptojEDj53JKAoZn?)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on July 03, 2014, 09:35:56 AM
Sound files between the RK47 capsule and Cathedral Pipes (Dale) M7.

Wow - They're SO different!

I also have the Cathedral Pipes "Dale M7" capsule in my MK47 (PCB) mic, and it sounds pretty fine there, too!
I kind of recognise the "weight" that I hear in your recording from that capsule, I guess.

It partly makes me curious to try something more akin to a traditional K47 capsule in my MK47 mic at some stage, to hear the difference, and it also makes me feel like I should get of my butt and complete my 2x D-U47fet PCB's some time!

Thanks for sharing.
Evan
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on July 03, 2014, 09:39:22 AM
Hi Guys, Finally I got my hands on another capsule. It was supposed to be for my M49B build, but it ain't coming out of this mic in a hurry. I'll have to order another.

Sound files between the RK47 capsule and Cathedral Pipes (Dale) M7.
No processing apart from gain matching.
No creamy pre just recorded through an A&H QU24 console into Cubase 7

Love the Dale M7! So smooth

Also the test confirms my thoughts, the RK-47 (well the one I bought anyway) is junk.



RK-47
https://www.dropbox.com/l/Lqt3IhDnIgmfLLQ3K2NAAq? (https://www.dropbox.com/l/Lqt3IhDnIgmfLLQ3K2NAAq?)

M7
https://io.groupdiy.com/file/gdiy-2017/u/39511/58d02819942af? (https://io.groupdiy.com/file/gdiy-2017/u/39511/58d02819942af?)

Thanks For taking the time to record these samples,
I Love the accent as well, we dont have those arround here :)
always appreciated,
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: EvLoutonian on July 03, 2014, 09:48:28 AM
I Love the accent as well, we dont have those arround here :)
Haha - Kiwi accent?
I wasn't sure if it's "bonza" Ozzie accent or "minty" Kiwi.     -Maybe different depending on which capsule?    ...harr harr
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Bassniac on July 03, 2014, 03:13:30 PM
I built one Mic with an RK7 capsule and one with the generic K47 -Beesneez capsule. Both sound just fine for the money. The one with the K47 was a budget project for a friend. My own with the RK7 will be mainly used on Bassdrumd and Speaker Cabs so i didnt see the point putting in a more expensive capsule. Cant go wrong with both of them.

Did anyone check the Advanced Audio capsules?

Cheers.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: OPR on July 03, 2014, 11:19:35 PM
Quote
Did anyone check the Advanced Audio capsules?

I'm 99.9 %sure the RK7 And AA capsule are the same thing. ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Andydrum82 on July 16, 2014, 09:22:19 AM
Hey Just finished mine. It sounds great. I used the Beesneez AK47 capulse
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Andydrum82 on July 16, 2014, 09:23:40 AM
And another picture
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on July 28, 2014, 02:28:55 PM
Hi Guys!

I'm reporting back to HQ here with my finished D-U47fet build!
It has a Cinemag CM-13101 and for the moment an RK-47 capsule.

I must say that I am very impressed with this mic!
It has authority, detail and presence. Basically a really good mic.

It is absolutely not dark, probably due to the RK47, and still handles sibilance very well.
It gives the detail of the TLM 103, without being harsh or thin, and with much more authority and punch. I really like it.

My plan was to change the capsule to a Thiersch or original Neumann once it was operational, but now I'm not sure anymore..
I think the RK47 performs really well in this config, and I can imagine it will sound very good on acoustic guitar.
It will probably work great as vocal mic too in many situations. 

So the new plan now is to build another one with a Neumann capsule and see if the difference is worth the money.

A big shout out to Poctop for making this wonderful kit, and to Chunger for making the GT-2B bodies available to us!

Best regards,
Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on July 28, 2014, 02:36:42 PM
Another pic of the D-U47fet with its clothes on, hard posing on the console.

Hmm...should I powder coat it..?
Maybe matte black as the cool looking one MicDaddy did?  8)

//Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on July 29, 2014, 12:48:36 PM
Another pic of the D-U47fet with its clothes on, hard posing on the console.

Hmm...should I powder coat it..?
Maybe matte black as the cool looking one MicDaddy did?  8)

//Michael

 :) :) :),
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: taliska on August 27, 2014, 08:29:56 PM
Hey all,

Just thought I'd post and chime in on my findings after finishing off my fet47. I used a cinemag 13101 and RK47 in my build.

Good points: straight forward build, t.bone body is solid.

Bad points: rk47 has got horrible mids. On voice will only be useful if keeping to a lower register, or wanting something approaching a telephone style effect. I'm going to try it on acoustic guitar as a last chance, but in all likeliness I'll be putting the stock capsule back in tomorrow.

<edit> Take the next bit with a pinch of salt, I may have been a little harsh... (I've kept it in there as it was my actual initial reaction) </edit>

To sum up, the 32mm capsule that came with the t.bone sounds more balanced and takes eq better than the RK47. Of course, perhaps that's what a 47 is supposed to sound like, but I highly doubt it. Seriously, I'm usually pretty reserved when it comes to product criticism, but do yourself a favour and choose something else...anything else...

Cheers,

Kaz
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on August 28, 2014, 06:29:28 AM
Hey Taliska,

I understand your frustration in not liking your mic!  :-[

However, what you describe does not sound like my build at all, and there are several others here who have liked their U47fet builds.
I have compared it to several other good mics I have (Neumann, Manley and my C12, M251 builds etc.), and I think I would have noticed if it would have "horrible mids".

Maybe you got a bad RK-47 capsule? Or perhaps the wrong value in a component? Maybe something got overheated? Contamination? Ground issue?
These are just suggestions that you might go over the circuit again and double check for errors before you discard this (in my opinion) wonderful mic!

I am actually so fond of it that I am building another one right now, so I strongly suggest that you give it another try..  :D

BTW: Did you make the self bias (I did) or the a bit more tricky one?
Let us know what you find!

Best,
Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: taliska on August 28, 2014, 09:04:55 AM
Hey Taliska,

I understand your frustration in not liking your mic!  :-[

However, what you describe does not sound like my build at all, and there are several others here who have liked their U47fet builds.
I have compared it to several other good mics I have (Neumann, Manley and my C12, M251 builds etc.), and I think I would have noticed if it would have "horrible mids".

Maybe you got a bad RK-47 capsule? Or perhaps the wrong value in a component? Maybe something got overheated? Contamination? Ground issue?
These are just suggestions that you might go over the circuit again and double check for errors before you discard this (in my opinion) wonderful mic!

I am actually so fond of it that I am building another one right now, so I strongly suggest that you give it another try..  :D

BTW: Did you make the self bias (I did) or the a bit more tricky one?
Let us know what you find!

Best,
Michael

Hi Michael,

Thanks for the support! ;)

I think it probably comes down to expectations vs personal preference quite a bit. I'm not saying it's completely unusable, but just falls outside what I would call useful based on the way I would like to work which is as follows (I'm a hobbyist so my techniques are a work in progress):

- Try to get the source sounding roughly correct on the way in (we're not talking about nailing it, just ballpark, generally with a max of a couple of tweaked eq bands on the way in).
- Once ITB, "nudge" the sound in the right direction with a little more eq to make it work in the context of the arrangement.
- The idea is basically sound refinement by a few minor tweaks, rather than taking big leaps.

Now I have nothing against "coloured" mics, but super coloured mics are almost always going to fall down on that first step. I'm probably always going to choose something else if the frequency response is too biased, which is where I'm at with the RK47.

I don't have a huge mic collection, but I'm trying to cover the bases slowly. All my points of reference are first-hand store bought specimens. I've got a K2, C214, RE20, and a SM58 to compare it to. I like to experiment with various styles, and I've got a selection of (cover) tracks that I've set up projects for in Logic that I try all those mics on for the sake of comparison and they (my other mics) all basically work without having to try too hard (lost kitten-metric, since i fell for you-nina simone, walkaways-counting crows, wicked game-chris isaac). I can honestly say that the K2/C214/RE20 are all awesome and are all equally likely to be chosen as the best fit for a particular song even though they're quite different sounding (K2 I would say is dark-ish, C214 is crisp, RE20 is somewhere in the middle plus has that whole different sound due to how dynamics handle transients).

I also did my first power up with the stock capsule and the sound was actually quite usable apart from the slight raspiness (I'm referring to sound quality here, not frequency response) at the top end which I expect to hear with cheap capsules.

Today I've tried the RK47 on acoustic guitar and the problem I have with it is this: I can actually make it sound quite nice once I'm ITB...where it fails is just at a common sense level. If I'm having to try too hard to make it sound good, then it's probably not a good choice. Again, I managed to get it sounding pretty nice, but I don't expect to have to be so surgical with my eq for a mic that's capturing ordinary sources in ordinary situations.

Oh and yeah, I suppose I should elaborate on horrible mids. That's what I thought I was hearing, but after more investigation today, I'd say it's got more to do with some pretty strong roll-off from 5khz upwards. In fact, what I'm hearing is pretty much exactly the graph they have on their site. I've attached it for reference. The rk47 might work better in a circuit that exaggerates the high frequencies, but I don't feel that the d-47 is that kind of circuit (just because I've never read that complaint in this thread).

At this point I'm pretty confident in my building abilities and the reasonable response from the stock capsule makes me think that things are working as they should. Check my post history for context, but I've been getting my hands fairly dirty for a while now, and while I'm lacking a bit in terms of the theoretical aspects of being a solder monkey, I don't think I've made a mistake in the build, especially as things tally with the mparts graph.

Anyway, I'm glad that you're getting on with your RK47 ok. :) Apologies if I came off a little bit harsh in my previous post...I'm not trying to get anyone in trouble, but I also can't see other people finding this capsule particularly usable in this circuit and I wanted to provide another viewpoint to balance out your previous enthusiastic post (it was actually your post that motivated me to try it out...before that I was going to avoid it as that guy posted samples compared with a dale m7, which had put me off getting it).

To sum up, the RK47 didn't sound like I expected it to, but it's entirely my own fault. It matches the graph they publish, but I just didn't think it would be that extreme. As always, this is just my opinion and other people should feel free to make up their own minds! ;)

Cheers,

Kaz

P.S. Here's a link to some screenshots of eq settings in logic that I had to use to push the raw recordings where I wanted them. For these I didn't use any eq on the way in, as the rk47's freq response was something of a mystery at the time. For anyone not familiar with the UI, for each track (vocal, guitar) I've included two images (pre-eq-curve, post-eq-curve). The eq settings are the same between pre and post images, but different between vocal and guitar images for obvious reasons. It's the frequency distributions at the bottom of the images that you should compare. The pre and post screenshots weren't taken at corresponding moments in time, so shouldn't be compared precisely, but rather just used to examine the trends.

https://www.dropbox.com/sh/9878lr9aa22tfvy/AADBsy8c-hhuhHhLcQjzhlN4a?dl=0
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on August 28, 2014, 02:05:48 PM
Thx for your elaborate response, I think I understand where you come from a bit better now!  :)

Your reference mics are what one could call "modern sounding" in that sense that they are quite open in the higher frequencies.
The U47fet is more of a vintage sounding mic, and the K-47 capsule is part of that. Ironically, the RK-47 is too much on the "bright" side for some..  :-\

If you prefer modern mics, you will find most vintage mics "dull".
People who prefer vintage mics will find modern mics "over bright".

So I guess it is just up to what you are used to, what you like and what you expect to hear.

Bear in mind that the DIY scene is quite focused on the vintage "unobtainable" mics, since good quality modern mics, like your AKG, are available cheaper than the cost of building one..
I am sorry if I mislead you to think that the D-U47fet is a bright and modern sounding mic. I was speaking in relative terms, trying to be politically correct.
Some people here would certainly discard "my" U47fet for being too bright (although for what we do, I think it is absolutely perfect!).

Take a look at the Numann TLM103 if you haven't tried it. It can be had quite cheaply second handed.
It is a high quality modern sounding mic. Too bright for some, but no doubt very usable for modern recordings, and sits well in a mix without too much tweaking.
It may work for you! We have used it a lot.

Given that there is nothing wrong with your capsule it may just be that you, as you point out, do not like the darker character of the U47fet.
But I strongly urge you to give it some time. Let the electronics "burn in" for a couple of days (although not a tube mic), record some more and try to get the feel for its relative qualities.
Maybe you will learn to appreciate it for what it does?

I come from the same "modern mic" background as you, so I have made the same journey!  :)

Best,
Michael
 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: taliska on August 28, 2014, 05:39:20 PM
Thx for your elaborate response, I think I understand where you come from a bit better now!  :)

Your reference mics are what one could call "modern sounding" in that sense that they are quite open in the higher frequencies.
The U47fet is more of a vintage sounding mic, and the K-47 capsule is part of that. Ironically, the RK-47 is too much on the "bright" side for some..  :-\

If you prefer modern mics, you will find most vintage mics "dull".
People who prefer vintage mics will find modern mics "over bright".

So I guess it is just up to what you are used to, what you like and what you expect to hear.

Bear in mind that the DIY scene is quite focused on the vintage "unobtainable" mics, since good quality modern mics, like your AKG, are available cheaper than the cost of building one..
I am sorry if I mislead you to think that the D-U47fet is a bright and modern sounding mic. I was speaking in relative terms, trying to be politically correct.
Some people here would certainly discard "my" U47fet for being too bright (although for what we do, I think it is absolutely perfect!).

Take a look at the Numann TLM103 if you haven't tried it. It can be had quite cheaply second handed.
It is a high quality modern sounding mic. Too bright for some, but no doubt very usable for modern recordings, and sits well in a mix without too much tweaking.
It may work for you! We have used it a lot.

Given that there is nothing wrong with your capsule it may just be that you, as you point out, do not like the darker character of the U47fet.
But I strongly urge you to give it some time. Let the electronics "burn in" for a couple of days (although not a tube mic), record some more and try to get the feel for its relative qualities.
Maybe you will learn to appreciate it for what it does?

I come from the same "modern mic" background as you, so I have made the same journey!  :)

Best,
Michael

Hi Michael,

Thanks for the feedback. Yeah, it's quite possible that it will grow on me, so I'm going to give it some time and see how things go.

Regarding the dull vs bright stuff. Don't worry I wasn't misled by your description in your original post, I acted upon it more because of how happy with the result you were than anything else, but that's totally on me! ;)

I was certainly expecting something a little different than my usual mics frequency response wise and that was part of the reason for building this...(I haven't got much use for microphones that all sound the same!)

I'm feeling a bit better about the sound at the moment, though I'm not really hearing the big bottom end that I was expecting from the 47fet so I'll keep on experimenting and see what happens.

FWIW, those previous eq curves were for a rather bright song, definitely brighter than I'd normally go, so that probably doesn't quite give an accurate representation of my typical target, but that was kind of the point...it was an exercise in trying to make it work in a situation where I just put up my c214 and recorded with minimum tweaking. Perhaps it was a flawed comparison from the start!

I'll stop polluting this thread now, but just to help those that come after me, and also to give you a bit more context on why I think it's lacking in bass, here's a clip (forgive the singing and the room! ;) ):

https://www.dropbox.com/s/f6oyxhzb174pesf/tired%20of%20you-snippet.wav?dl=0

First take is C214, followed by RK47, followed by RE20 (with high pass engaged on mic).

Chain: mic -> SSL9k500 -> EQN(bypassed) -> F76 -> audio interface.

Completely flat, nothing applied apart from the side chain HPF on the F76...which should make the bass more obvious I guess. I think my C214 & RE20 both have more bass than the rk47...

Cheers,

Kaz
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on August 29, 2014, 02:48:22 PM
The Capsule Plays a Major Role in the sounds of this mic ;) it does not have a very complex feedback circuitry for taming the HF as per neumann capsule needs,

Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kidvybes on August 29, 2014, 06:02:22 PM
I'll stop polluting this thread now, but just to help those that come after me, and also to give you a bit more context on why I think it's lacking in bass, here's a clip (forgive the singing and the room! ;) ):

https://www.dropbox.com/s/f6oyxhzb174pesf/tired%20of%20you-snippet.wav?dl=0

First take is C214, followed by RK47, followed by RE20 (with high pass engaged on mic).

Chain: mic -> SSL9k500 -> EQN(bypassed) -> F76 -> audio interface.

Completely flat, nothing applied apart from the side chain HPF on the F76...which should make the bass more obvious I guess. I think my C214 & RE20 both have more bass than the rk47...

Cheers,

Kaz

...to best judge a vocal mic on a particular voice, it's sometimes more productive to evaluate with a backing track similar to what will be used in the actual final mix...often, what vocal track sounds best soloed, will not be the best choice when combined with the other backing tracks...in most cases, during the mix process, you'll be rolling of low-end on the vocal track anyway, so mids are more critical...of the 3 mics on that clip you posted, the RK47 sounds fine, IMHO...

...try putting those clips on the intended backing track and listen again...it may change your entire perspective...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: taliska on August 30, 2014, 10:52:39 AM
...to best judge a vocal mic on a particular voice, it's sometimes more productive to evaluate with a backing track similar to what will be used in the actual final mix...often, what vocal track sounds best soloed, will not be the best choice when combined with the other backing tracks...in most cases, during the mix process, you'll be rolling of low-end on the vocal track anyway, so mids are more critical...of the 3 mics on that clip you posted, the RK47 sounds fine, IMHO...

...try putting those clips on the intended backing track and listen again...it may change your entire perspective...

Thanks for the guidance kidvybes. I'm not overly experienced as you can probably tell, so my whole adventure in DIY is part of my commitment to spending more time learning about this stuff and it all definitely helps! ;)

Yeah, those takes were just for test purposes, so nothing to put them up against, but I take your point. I've actually been dealing with that very issue today in a busy mix. I decided to stay up until 3am last night noodling on my acoustic guitar in logic with the RK47 to try and get a feel for it. I'm actually liking it quite a lot for guitar at the moment. Once it's EQ'd it seems quite full and umm "blurry" (in a nice way!) for want of a better word. Obviously can't say how much of that is the capsule, transformer, or circuit...but hey, it's working at least!

Of course as these things do, it all got out of control and my guitar noodling turned in to some kind of attempt at an emo-rock song. It probably started off with around 6 acoustic tracks and nothing else, and ended up with 3 acoustic tracks and a massive drop in to a short distorted rock chorus. I ended up with so many tracks (for me anyway), that it was certainly a task to notch out all the various bands to make it work. It's still a bit busy, but it kind of got there in the end. Anyway, my reason for mentioning that is that in the chorus refrain, I think I decided to use the RE20 as it seemed to be working best for those vocal lines...but because it has to weave in between the main vocal line for the chorus, it did indeed end up being heavily cut at the top and the bottom.

I've attached a screenshot of the eq I ended up using on the RE20, and as you say, clearly the rk47 frequency response wouldn't have been a problem being used in that situation given that amount of cutting I needed to do to make the lines sit right.

The jury's still out a little bit on how well it will work on my vocals, but it's all good fun and I'm totally happy to put the time in to work out it's intricacies...

Cheers,

Kaz
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kambo on September 12, 2014, 12:12:40 AM


Also the test confirms my thoughts, the RK-47 (well the one I bought anyway) is junk.



i dont think its fare to compare 100$ capsule to 325$ capsule...
(unless u paid 300$ for ur rk-47)

i have one with cheap capsule too,
it gives incredible sparkle, when combined with coles 4050 8)



Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Nyquist on September 12, 2014, 08:02:27 AM
Plenty fair I think. I have a RK-87 and it sounds very good and extremely close to the original. As I said the RK-47 I bought was junk. Does not mean others out there are. 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kambo on September 12, 2014, 12:18:04 PM
i think u are not understanding what i am trying to say.
we dont call other peoples products junk here, u may go to grsltz and call it what ever u wanna call...

respect...

if its not sounding good enough for you, its not good enough.... thats fair...
i listened to your recordings... there is nothing sounding junk...
you have no respect at all....

 



Plenty fair I think. I have a RK-87 and it sounds very good and extremely close to the original. As I said the RK-47 I bought was junk. Does not mean others out there are.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kidvybes on October 12, 2014, 04:30:03 PM
One has to wonder if all the interest in DIY classic mic clones was the inspiration for Neumann's (Sennheiser) latest decision to re-issue the 47fet...a friend at the AES show said that the Neumann rep said that based on the interest in this 47fet re-issue, they may decide on additional classic re-issues for the future...I suspect the DIY clone market was an, albeit small, but still a partof that decision making process at the Sennheiser headquarters...

http://www.u47fet.neumann.com/content/en/index.html
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 14, 2014, 05:16:39 PM
One has to wonder if all the interest in DIY classic mic clones was the inspiration for Neumann's (Sennheiser) latest decision to re-issue the 47fet...a friend at the AES show said that the Neumann rep said that based on the interest in this 47fet re-issue, they may decide on additional classic re-issues for the future...I suspect the DIY clone market was an, albeit small, but still a partof that decision making process at the Sennheiser headquarters...

http://www.u47fet.neumann.com/content/en/index.html

I guess only the Price of this mic is not vintage ......  :o,
Best,
dAN
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kidvybes on October 14, 2014, 11:57:20 PM
I guess only the Price of this mic is not vintage ......  :o,
Best,
dAN

...that's true, but to some, the difference in cost is qualified by the "badge"...
...certainly not me!
 ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on October 15, 2014, 05:11:56 AM
It's a single pattern, transistor microphone is what it is.
The price is madness.
But they own the goldmine name, so the market will bear it.
OK, perhaps they had to do some tooling to get things precise.
On the other hand, they may have had enough spare parts to do a hundred pieces (similar to the scenario when the U67 was reissued).

BTW, I think it's no coincidence they came with this reissue now.  ;)


Henk
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: RuudNL on October 15, 2014, 05:41:21 AM
Someone recently asked my why the price of the Neumann microphones is so high?
I grabbed a U87 and pointed with my finger to the small square logo plate on the body.
"You see this?" I said, "This is a VERY expensive part of the microphone"...

(By the way: good to see you back Micaddict!)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mappyo on November 11, 2014, 03:39:08 PM
Hi all,

I have come close to finishing my FET47 build. I have a question about the capsule connections. My capsule has both a front and a back diaphragm. I see the markings for FD, front diaphragm, and BCK, backplate. I don't know what to do with the back diaphragm connection. Any suggestions?

Here is a picture  of my build so far. 

Thank you in advance for your help!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 11, 2014, 04:15:05 PM
Hi all,

I have come close to finishing my FET47 build. I have a question about the capsule connections. My capsule has both a front and a back diaphragm. I see the markings for FD, front diaphragm, and BCK, backplate. I don't know what to do with the back diaphragm connection. Any suggestions?

Here is a picture  of my build so far. 

Thank you in advance for your help!

Very Nice build  :),   the back diaphrgame in this build is not connected just isolate the wire and leave it where it wont comes loose or create microphonics noise in the headbasket ,

Let Us know how this thing works out ,  i am jealous  ;),

Best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mappyo on November 11, 2014, 05:53:23 PM
Hi all,

I have come close to finishing my FET47 build. I have a question about the capsule connections. My capsule has both a front and a back diaphragm. I see the markings for FD, front diaphragm, and BCK, backplate. I don't know what to do with the back diaphragm connection. Any suggestions?

Here is a picture  of my build so far. 

Thank you in advance for your help!

Very Nice build  :),   the back diaphrgame in this build is not connected just isolate the wire and leave it where it wont comes loose or create microphonics noise in the headbasket ,

Let Us know how this thing works out ,  i am jealous  ;),

Best,
Dan,

Thank you!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on November 21, 2014, 06:43:54 PM
Hey guys,

Yesterday the missing WIMAs came from Mouser so I could finish my second D-U47fet. Now we can make stereo recordings with them!

I finally went for the black powder coating with some structure. I left the headbasket as is though. Viery happy with the result, and love the sound!

Thanks again Poctop for this wonderful PCB!

Cheers,
Michael

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jrasia on December 18, 2014, 02:06:09 PM
Hi, 

I have a couples questions before starting assembly of PCB 'B' of this build.  Particularly about the pad network.  I've read through the posts but still not %100 clear.
I'm using the cm3101 tranny, Styroflex caps, with Eric's hk47 on its way.  I'm trying to stay as truthful to the original u47FET as possible.

With that;

1.  What do the resistors options (33M vs 2x68m) translate to in terms db padding level.  If that's indeed what these resistors options are used for?  Does one offer more padding level than the other, or are they simply what was in stock and available through the BOM?

2.  Further, can someone also clarify the jumper settings for s1a, s1b so I know how to properly engage the pad?  I don't believe I'll be using a switch, but rather simply using jumpers on the pcb.  If I understand correctly, no jumpers, or jumpers in the same position on s1a, and s1b is the equivalent as NO PAD, but what is the correct jumping setting to engage it?  Does it matter exactly which pins and as which position?

Apologies, for the rookie questions.  I'm sure there will be more:)

Thanks



Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Andydrum82 on December 22, 2014, 06:00:39 PM
I just fitted a Beesneez M7 capsule to my u47fet. I will try to get back to you with the results
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: lyricalgeek on January 19, 2015, 02:29:59 PM
Does the JFet IDSS matter with this circuit like the U87 as far as Gain and headroom is concerned? I have the following 2n3819 IDSS's 6.80ma, 7.13ma, 7.21ma, 8.29ma and 8.61 ma. What would be the ideal FET IDSS be?

Thanks  :)

Bump
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 19, 2015, 03:29:17 PM
Does the JFet IDSS matter with this circuit like the U87 as far as Gain and headroom is concerned? I have the following 2n3819 IDSS's 6.80ma, 7.13ma, 7.21ma, 8.29ma and 8.61 ma. What would be the ideal FET IDSS be?

Thanks  :)

Bump

6.80ma
 ;)
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on January 23, 2015, 06:23:13 PM
Hi fellas,
what kind of capsule can or should I use for this nice U47-FET Project and were can I get them?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on January 24, 2015, 07:49:06 AM
Hi fellas,
what kind of capsule can or should I use for this nice U47-FET Project and were can I get them?

If you want to stay close to the original you need a K47 capsule. The cheapest ones are China made; the most expensive one is the K47/49 from Neumann itself.

Between those extremes there are other options. 
And worth mentioning are the hybrids (best of two worlds) designs by BeesNeez (K7; K47 meets M7) and tskguy (double backplate K47).
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on January 24, 2015, 09:47:18 AM

@ burn4ever:You should update your profile.Where are you located?I'm happy with my Thiersch M7,available here in germany.


Udo.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on January 24, 2015, 10:17:55 AM
Yes, M7 was K47's predecessor. It was never in the U47fet, but it has a similar vibe.
Thiersch does those well.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 02, 2015, 02:29:22 PM
Where are the 18pf Styroflex/630V and  33pf styroflex/630V, that are mentioned above, in use?
Can´t see no one at this documentation.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 02, 2015, 02:58:28 PM
Where are the 18pf Styroflex/630V and  33pf styroflex/630V, that are mentioned above, in use?
Can´t see no one at this documentation.

when i had done the demonstration of mounting the pcb i did not have them available ,
but they are used in this build   for C2 and C3,
hope this helps, see schematic,
Best,
dAn,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 02, 2015, 04:06:07 PM
Where are the 18pf Styroflex/630V and  33pf styroflex/630V, that are mentioned above, in use?
Can´t see no one at this documentation.

when i had done the demonstration of mounting the pcb i did not have them available ,
but they are used in this build   for C2 and C3,
hope this helps, see schematic,
Best,
dAn,

Alright, I see.
I wonder cause at the PCB PDF the 18pf and 33pf (C2, C3) are declared with 160V and not  with 630V
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 05, 2015, 01:32:30 PM
Where are the 18pf Styroflex/630V and  33pf styroflex/630V, that are mentioned above, in use?
Can´t see no one at this documentation.

when i had done the demonstration of mounting the pcb i did not have them available ,
but they are used in this build   for C2 and C3,
hope this helps, see schematic,
Best,
dAn,

Alright, I see.
I wonder cause at the PCB PDF the 18pf and 33pf (C2, C3) are declared with 160V and not  with 630V

160V there will also be fine ,  most of the styroflex available are 50V please avoid those
I supply 630V they are small package and much more robust.
Best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 07, 2015, 05:51:10 AM
Well, it´s me again  ;)
Are there any documentations how to calibrate the Trimmer Resistors and how to connect (solder) the capsule?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 07, 2015, 10:13:19 AM
Well, it´s me again  ;)
Are there any documentations how to calibrate the Trimmer Resistors and how to connect (solder) the capsule?

the Pot was only for testing purposes so if you installed it anywhay , you don't have to adjust anything ,
you can also decide to not installed it and follow this procedure.
as far as the capsule goes , check on the first page  tutorial , the front diaphgrame connect ( floating to the 1G resistor )
and the backpate of the capsule goes to a jumper-pad labeled BCK only one of the pad goes to gnd.


(http://dl.dropbox.com/u/43869772/U47/PIC%20GT/Terrebonne-20121015-00602.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d02819944b6.jpg)

Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 08, 2015, 12:19:28 PM
Sorry, but the BOM seem don't be correct. That's normal?
I found caps/resistors who shouldn't be here, because there aren't on the schematic?

I don't found those caps and others in the BOM...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 08, 2015, 01:51:32 PM
Sorry, but the BOM seem don't be correct. That's normal?
I found caps/resistors who shouldn't be here, because there aren't on the schematic?

I don't found those caps and others in the BOM...

Those capacitors are in the BoM but they are not electrolytics as in this pictures as they were not available at this time ,
they are actually Tantalum Capacitors,  note that tantalum capacitors are polarized.

here is an excert from the current BOM,

https://ca.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=4bdecadc37

also if you hit the refresh key while viewing  the BOM form mouser , you will be able to see all the notes in the customer part number column it tells alternative part number as well as part that are optional if you some others are available,



 Mouser #:  80-T356E475K035AT 
 Mfr. #:  T356E475K035AT 
 Manufacturer:   Kemet 
 Desc.:  Tantalum Capacitors - Solid Leaded 4.70uF 35.0V10% 
 RoHS:   RoHS Compliant 
 Availability
1  Ships Now
 $1.78  $1.78


Mouser #:  80-T356A334K050AT 
 Mfr. #:  T356A334K050AT 
 Manufacturer:   Kemet 
 Desc.:  Tantalum Capacitors - Solid Leaded 50volts 0.33uF 10% 
 RoHS:   RoHS Compliant 
 Availability
1  Ships Now
 $1.29  $1.29


Mouser #:  80-T356B105K050AT 
 Mfr. #:  T356B105K050AT 
 Manufacturer:   Kemet 
 Desc.:  Tantalum Capacitors - Solid Leaded 1.00uF 50volt 10% 
 RoHS:   RoHS Compliant 
Availability
2  Ships Now
 $1.46  $


Best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 08, 2015, 04:49:27 PM
Ok, thanks Dan !

In the BOM, There are a 1000pf - 400v (505-MKP21000/400/5). It's a replacement caps instead of 2200pf at C1?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 08, 2015, 05:05:28 PM
Ok, thanks Dan !

In the BOM, There are a 1000pf - 400v (505-MKP21000/400/5). It's a replacement caps instead of 2200pf at C1?

yes it is an option , original value is 2200pf,  note says option gate coupling cap,
I think I will remove this to avoid confusion in a later time ,  Thanks
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 08, 2015, 05:18:25 PM
Ok, thanks Dan !

In the BOM, There are a 1000pf - 400v (505-MKP21000/400/5). It's a replacement caps instead of 2200pf at C1?

yes it is an option , original value is 2200pf,  note says option gate coupling cap,
I think I will remove this to avoid confusion in a later time ,  Thanks
Best,
Dan,
Thanks again, and a last question.

I don't want to buy styroflex, 'cause I don't found in Europe (I'm French) and buy them in USA, it's too much.

So, if I remplace them by Mica 18pf - 500v and Mica 33pf - 500v? Like that :

18pF :
http://www.mouser.fr/ProductDetail/Cornell-Dubilier/CD15CD180JO3F/?qs=sGAEpiMZZMtLiKaZgV7flaroxyCpcgny9mqIOjWCBkQ%3d

33pF :
http://www.mouser.fr/Search/ProductDetail.aspx?R=CD15ED330GO3Fvirtualkey59850000virtualkey598-CD15ED330GO3F

Thanks
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 08, 2015, 05:23:47 PM
Ok, thanks Dan !

In the BOM, There are a 1000pf - 400v (505-MKP21000/400/5). It's a replacement caps instead of 2200pf at C1?

yes it is an option , original value is 2200pf,  note says option gate coupling cap,
I think I will remove this to avoid confusion in a later time ,  Thanks
Best,
Dan,
Thanks again, and a last question.

I don't want to buy styroflex, 'cause I don't found in Europe (I'm French) and buy them in USA, it's too much.

So, if I remplace them by Mica 18pf - 500v and Mica 33pf - 500v? Like that :

18pF :
http://www.mouser.fr/ProductDetail/Cornell-Dubilier/CD15CD180JO3F/?qs=sGAEpiMZZMtLiKaZgV7flaroxyCpcgny9mqIOjWCBkQ%3d

33pF :
http://www.mouser.fr/Search/ProductDetail.aspx?R=CD15ED330GO3Fvirtualkey59850000virtualkey598-CD15ED330GO3F

Thanks

there is no problem on doing that too, that is the beauty of DIY sometimes you have to take what you have in hand to make it work,
Best,
dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mappyo on February 09, 2015, 03:13:03 AM
Just want to chime in here to say I've been really enjoying using this mic. I had a great time building it and am thrilled that it works and sounds good. I decided to use the Thriersch red line capsule and a Cinemag CM-13101 transformer.

I've found this combination to have a full low end with a bit of high mid presence. It has kind of a mellow top end in a nice way. It's definitely very usable on many instruments. It sounds full and rich. The mic's rejection comes in quite handy when micing a bass drum or bass amp too.

Here's a link to a soundcloud playlist with some samples:
https://soundcloud.com/mappyo/sets/dfet47-samples

Hope this is of interest. I'm looking forward to making more mics.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on February 09, 2015, 11:52:14 AM
Thanks for sharing!
On "Far far away",is it the D-U47 on the vocal?If so,what was the chain?


Best,


Udo.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mappyo on February 09, 2015, 01:10:32 PM
Hey Udo,
It was the D-47FET on the vocal. The chain was a classic api VP28 into a leviathan opto compressor, taking off at most 3 dB's. Then into lynx converters straight to protools. There wasn't any EQ. For "Far Far Away" I did put a limiter on the 2-bus, but it is hardly doing any gain reduction at all, maybe a decibel here and there. There isn't any limiting on the bass and bass drum tracks though.

Best

Thanks for sharing!
On "Far far away",is it the D-U47 on the vocal?If so,what was the chain?


Best,


Udo.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kante1603 on February 09, 2015, 01:22:15 PM
Sounds really great,congrats!VP28.....that gives some additional "magic" to the vocal,I have 8 of them.
Great Mic & PreAmp-Combo I must say!I use them nearly daily with U87s.....
Very nice indeed,


best,


Udo.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mappyo on February 09, 2015, 04:14:55 PM
Thanks!
Sounds really great,congrats!VP28.....that gives some additional "magic" to the vocal,I have 8 of them.
Great Mic & PreAmp-Combo I must say!I use them nearly daily with U87s.....
Very nice indeed,


best,


Udo.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: gevermil on February 10, 2015, 11:07:06 PM
This build with a Beesneez K7 is very nice .
It was impressive in a shoot out with a few expensive mics .
I used a cinemag transformer and a old equinox U47 body .


Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 11, 2015, 02:03:24 PM
Hi everyone !

Sorry, but I search and search for this part... And I don't found it on Mouser... An idea?

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 11, 2015, 02:09:55 PM
Hi everyone !

Sorry, but I search and search for this part... And I don't found it on Mouser... An idea?

send a PM to Mappyo i might be able to help on this find as this one is its build ,
Best,
Dan,
or you could practice on mousering it ,  i bet you can find it ,
once you get use to mouser you can find about anything ( they have)
if you need a clue check here ,
http://ca.mouser.com/Connectors/Terminal-Blocks/Fixed-Terminal-Blocks/_/N-7rqd7/?

 ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 11, 2015, 02:34:31 PM
Freeeeeeeeeeeeedoooom ! Thanks ahah ;D

Finally ! http://www.mouser.fr/ProductDetail/Phoenix-Contact/1725672/?qs=sGAEpiMZZMvZTcaMAxB2AF3qQv3QF5c1cqzdDV%2fmZgo%3d (they show 10P in pic, but it's a 4P) great !  :D

It's the good pitch? 2,54mm?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 11, 2015, 03:04:38 PM
Freeeeeeeeeeeeedoooom ! Thanks ahah ;D

Finally ! http://www.mouser.fr/ProductDetail/Phoenix-Contact/1725672/?qs=sGAEpiMZZMvZTcaMAxB2AF3qQv3QF5c1cqzdDV%2fmZgo%3d (they show 10P in pic, but it's a 4P) great !  :D

It's the good pitch? 2,54mm?

Do not remember by heart but user a ruler and check the pcb up,
i dont have acces to one right now,
dont worry about the pictures refer to the details and spec always,
D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mappyo on February 11, 2015, 04:48:11 PM
That's the exact part I used--2.54 pitch too.

Freeeeeeeeeeeeedoooom ! Thanks ahah ;D

Finally ! http://www.mouser.fr/ProductDetail/Phoenix-Contact/1725672/?qs=sGAEpiMZZMvZTcaMAxB2AF3qQv3QF5c1cqzdDV%2fmZgo%3d (they show 10P in pic, but it's a 4P) great !  :D

It's the good pitch? 2,54mm?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on February 11, 2015, 07:32:17 PM
Two happy FETs waiting for a stereo recording..  :)

Cheers!
//Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 13, 2015, 03:38:33 PM
Two happy FETs waiting for a stereo recording..  :)

Cheers!
//Michael
You painted it by yourself? Beautiful mics !
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on February 13, 2015, 07:06:15 PM
Thanks, acdc-angus!

No, I did not do it myself.
I had them powder coated here in Stockholm.

Considering the total cost of a project like this, I think it is worth the little extra cost to powder coat instead of using normal spray color. The finish and durability is so much better.

//Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 14, 2015, 06:19:11 PM
Hey fellas,
did I have to use the jumpers? But how?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 14, 2015, 08:17:42 PM
s1a s1b ,  jumper in both places  1 direction = pad
no jumper both position you can place the jumper only in 1 pin to let them hang there = no pad

LC = jumper on = low cut ,

Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 15, 2015, 02:02:55 AM
Thanks for the patience and quick reply Dan  ;)

Is it right that I have to use the 1000pF Capacitor instead the 2200pF for C1?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 15, 2015, 09:56:22 AM
Thanks for the patience and quick reply Dan  ;)

Is it right that I have to use the 1000pF Capacitor instead the 2200pF for C1?

use the 2200pf,
Dan
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 16, 2015, 12:53:23 PM
Sorry, what the difference between "pad" and "no pad"? I'm a noob... Ahaha ;D

Mouser orders done ! But Molex 2 headers wasn't available... So, I must wait until 20th March...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 24, 2015, 11:31:05 AM
Hi,

I have some wire from a JMP 2203 project. Can I use these for the U47Fet? (TR32 22 Awm 600v) XRL to PCB and link both side?

Thanks

That's my project for now

(https://lh3.googleusercontent.com/-AUvYLP89X9M/VOyXnDYFbCI/AAAAAAAAGRQ/JAa2FMEHq50/w500-h375-no/5.jpg)

(https://lh3.googleusercontent.com/-wwPjQmoVxJc/VOyX_AjjW7I/AAAAAAAAGRs/MzklCOIF9BI/w500-h375-no/6.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 24, 2015, 12:40:21 PM
Hi,

I have some wire from a JMP 2203 project. Can I use these for the U47Fet? (TR32 22 Awm 600v) XRL to PCB and link both side?

Thanks

That's my project for now

(https://lh3.googleusercontent.com/-AUvYLP89X9M/VOyXnDYFbCI/AAAAAAAAGRQ/JAa2FMEHq50/w500-h375-no/5.jpg)

(https://lh3.googleusercontent.com/-wwPjQmoVxJc/VOyX_AjjW7I/AAAAAAAAGRs/MzklCOIF9BI/w500-h375-no/6.jpg)
Nice Picture,
have you been using the 30M + 100M in the Z region connecting the fet ?
i see the R5+ spot is empty if you did then you are fine :)
you can use teflon isolated 26-27 gauge wire this is the best stuff ,
if not regular 26-27 gauge wire will do fine ,
if you use too big wire you will be missing the flexibility of the wire
Best,
DAn,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on February 24, 2015, 01:04:20 PM
Nice Picture,
have you been using the 30M + 100M in the Z region connecting the fet ?
i see the R5+ spot is empty if you did then you are fine :)
you can use teflon isolated 26-27 gauge wire this is the best stuff ,
if not regular 26-27 gauge wire will do fine ,
if you use too big wire you will be missing the flexibility of the wire
Best,
DAn,
Thanks !

Yes it's 30M and 100M. I wanted the minimum possible of composants. More easier to soldering

So, I can use my wire? If I don't need buying others, it's good ! Ahah

If not, I have this (picture below), can I take the wire on it to use in mic?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 25, 2015, 05:50:45 PM
Two happy FETs waiting for a stereo recording..  :)

Cheers!
//Michael
Looks very nice!
Were did you build these custom badges?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 27, 2015, 01:42:13 AM
Hey guys,
does anybody knows what kind of screws I need to fix the pcb to an GT-2B body?
The screws from this mouser list
http://www.vintagemicrophonepcbkit.com/DU47FET.html
are to big:
http://www.mouser.de/Search/ProductDetail.aspx?R=9300virtualkey53400000virtualkey534-9300

And what kind of cable diameter do you use to connect the components, like the transformer, to the pcb?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 27, 2015, 11:13:59 AM
Hey guys,
does anybody knows what kind of screws I need to fix the pcb to an GT-2B body?
The screws from this mouser list
http://www.vintagemicrophonepcbkit.com/DU47FET.html
are to big:
http://www.mouser.de/Search/ProductDetail.aspx?R=9300virtualkey53400000virtualkey534-9300

And what kind of cable diameter do you use to connect the components, like the transformer, to the pcb?

I Am under the impression that the screws should come with the GT-2B body but I may be wrong ,
the bracket and screw inside this current BOM is for the New version of the D-47FET pcb that will adapt the U47 style Mic
body,  if you don't need them you can skip them out of this BOM
IIRC the screws for the pcb to gt-2b are 2mm screws (M2).

(https://dl.dropboxusercontent.com/u/43869772/D47FET%20-Alctron%20Style/DMain47F.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281994515.jpg)
Best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 27, 2015, 11:39:42 AM
Hey Dan,
thanks.
No screws to mount the pcbs comes with the GT-2B body, but I think  to buy 6 extra screws is in my budget  ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on February 27, 2015, 12:42:23 PM
Is it possible to buy the Neumann k47, since now they are reissuing the mic?  Price?

The k67 is not very expensive, so if the k47 is in that range I'll go for the Neumann for #2.

I have one of ChuckD's m7 in my first, but he no longer offers the m7 to DIYers.

Thanks
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on February 27, 2015, 01:49:08 PM
Is it possible to buy the Neumann k47, since now they are reissuing the mic?  Price?

The k67 is not very expensive, so if the k47 is in that range I'll go for the Neumann for #2.

I have one of ChuckD's m7 in my first, but he no longer offers the m7 to DIYers.

Thanks

Quote
I have one of ChuckD's m7 in my first, but he no longer offers the m7 to DIYers.

I am Hoping To be soon able to fix this problem,
See Here:
http://groupdiy.com/index.php?topic=58663.0
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kidvybes on February 27, 2015, 05:26:24 PM
I am Hoping To be soon able to fix this problem,
See Here:
http://groupdiy.com/index.php?topic=58663.0

...and some of us continue to wait patiently...
 ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: burn4ever on February 28, 2015, 02:50:22 AM
I have a question to the position (mount) of the capsule.
This is a realy nice build from a member here, but
looks like the capsule sits to high, or am i wrong?

And does anybody have experience what kind of mound from Thiersch http://thiersch-mic.de/en/estm_produkte.html (http://thiersch-mic.de/en/estm_produkte.html) will fit into the GT-2B body? Mounts from Thiersch have hights from 52mm - 58mm. But I think these all to high for the GT-2B body.

(http://groupdiy.com/index.php?action=dlattach;topic=49758.0;attach=19570;image)

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on February 28, 2015, 04:56:33 AM
It sits pretty high in the original and there's a theory why that is.

I'll see if I can post the picture I have in mind.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on February 28, 2015, 05:08:15 AM
(http://www.twin-x.com/groupdiy/albums/userpics/normal_DSC01986.JPG)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: kidvybes on February 28, 2015, 10:35:33 AM
It sits pretty high in the original and there's a theory why that is.

I'll see if I can post the picture I have in mind.

...we have been having that debate over at realgearonline.com, as to whether the height of the capsule mount in the U47 was deliberate and if so, for what purpose...do the rumors it was designed to limit plosives/sibilance have any historical basis?...so I decided to reach out to a few "experts" and here's what they had to say about it...

Here's Klaus Heyne's thoughts on the positioning of the U47 capsule:

"The U47 capsule mount is at the end of a stiff rubber column whose height and material properties need to be an ideal compromise between elasticity (shock absorption) and stiffness (preventing the capsule to whiplash against the inside of the head basket after a shock). Making it shorter gets you into the territory of the C12 and its capsule mount problem: heavy subsonic Trittschall-transmission. The whole thing transmits too much at 20 hz and below when triggered with even the smallest external excitement.

The secondary, and probably unintended (positive) consequence of the column length Neumann chose is this: the higher you place the capsule inside the basket, the father away it gets from two parallel and reflective surfaces-the basket wall and the base plate-and the closer it gets to the domed (and diffractive) top.

Here is an experiment I have made a few times to understand the real-world consequences of an acoustical obstacle placed close to a diaphragm: mount the same CK12 capsule, once in a C12 (no obstacle in front of the front diaphragm) and then in a C24 (a nasty support bar crossing right through the middle of the front diaphragm): I cannot hear an difference.

That leads me to believe that the small circular weld connecting the U47's cylindrical basket with the domed portion of the basket must be quite negligible, acoustically.

I speculate that the capsule's proximity to the support/weld was known, considered, and found to be not a fatal flaw for the overall head design."



...I then got a response from David Bock :

"Nothing Neumann did, or does, is unintentional.

Even when they use series reg on re-issue U67 psu's (!!!!!), or internal switching psu on fet mics. Tells you everything.
Remember, they used to RUN the microphone world."



...And Toni Roger Fishman of Telefunken had this to say:

"The internal capsule mount has changed form the original design. The first 200 U47 had a mesh surround that was like a divider that split the head grill I will look for some photos and try to post them but this is very rare and hard to find as so many mics have been modified. This (pic below) is the real way it was to be set up but why they changed to what we see today would take much research to figure out.

The height is slightly shorter in the original and taller in the later units. It would be interesting to do some test with modified capsule mounts and heights. We may be willing to look into some tests as I've always wanted to make the earlier mount available to those that needed the parts to restore the fist 200 units to stock."
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on March 01, 2015, 08:34:44 PM
Some pics of my build.  Alctron GT-2B body, Advanced Audio AK47 capsule, AMI T49 transformer
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on March 01, 2015, 08:35:30 PM
Inside
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on March 01, 2015, 08:36:22 PM
other inside  ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: MicDaddy on March 03, 2015, 04:57:04 PM
Neumann returned my call today with pricing for what I asked for in the K47 capsule.

Their response was part #514753 at a cost of $587.86 USD.... but the message was choppy and I'm not even sure she understood clearly what part I was asking for.


I also didn't realize that the rear diaphragm wasn't sputtered?  That kind of kills the idea I had but would still be viable for this kit.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Patrick from Davis on March 03, 2015, 06:33:12 PM
It would be very interesting to get on and compare it to some of the offerings out there, but at that price...  Depending on shipping, that is about the cost of the whole thing with Tskguy's capsule.  I'd love to know, but that is hard to justify.
Patrick

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on March 04, 2015, 08:57:47 AM
What about grounding?

  The XLR pin1 can be in electric contact with the body where the XLR connector is set..
  The PCB can be in electric contact with the body via the screws...
  The PCB can be in electric contact with the body via a wire that is connected to XLR's pin1..

Should all these connections be made ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 04, 2015, 09:01:05 AM
Neumann returned my call today with pricing for what I asked for in the K47 capsule.

Their response was part #514753 at a cost of $587.86 USD.... but the message was choppy and I'm not even sure she understood clearly what part I was asking for.


I also didn't realize that the rear diaphragm wasn't sputtered?  That kind of kills the idea I had but would still be viable for this kit.

the Capsule that is not Sputtered on 1 side should be the K49 capsule , Since one of the side did not meet the machining spec for gaping distance for the backplate it is not sputtered , this is the capsule you will find in a tlm49 and style,
a K47 capsule should be on both side 100% sure,  in the case of the K49 it is a perfect match for this project beeingt only hypercardiod mic , but the price seems odd to me for a K47 Capsule,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 04, 2015, 09:13:45 AM
What about grounding?

  The XLR pin1 can be in electric contact with the body where the XLR connector is set..
  The PCB can be in electric contact with the body via the screws...
  The PCB can be in electric contact with the body via a wire that is connected to XLR's pin1..

Should all these connections be made ?

PCB Gnd will always have Gnd connection trough screw to chassis unless plastic screw are used  ;)
then you need to make sure xlr pin 1 is to mic chassis as well,
Best,
Dan,


Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on March 04, 2015, 09:22:01 AM
I'm asking because I'm fighting with a strange body to set everything together inside..
I should avoid ground loops I suppose?

  So XLR's pin1 always connected to the body, 2 options :
1 :  PCB to ground via the srews
2 : PCB to ground via a wire to XLR's pin1

  But not both at the same time right?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 04, 2015, 09:40:58 AM
I'm asking because I'm fighting with a strange body to set everything together inside..
I should avoid ground loops I suppose?

  So XLR's pin1 always connected to the body, 2 options :
1 :  PCB to ground via the srews
2 : PCB to ground via a wire to XLR's pin1

  But not both at the same time right?

PCB to mic chassis via screw  and XLR pin 1 to mic chassis via pcb xlr pin 1 pad and you will be fine ,
Best,
dAN,
 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on March 04, 2015, 09:43:28 AM
Neumann returned my call today with pricing for what I asked for in the K47 capsule.

Their response was part #514753 at a cost of $587.86 USD.... but the message was choppy and I'm not even sure she understood clearly what part I was asking for.


I also didn't realize that the rear diaphragm wasn't sputtered?  That kind of kills the idea I had but would still be viable for this kit.

the Capsule that is not Sputtered on 1 side should be the K49 capsule , Since one of the side did not meet the machining spec for gaping distance for the backplate it is not sputtered , this is the capsule you will find in a tlm49 and style,
a K47 capsule should be on both side 100% sure,  in the case of the K49 it is a perfect match for this project beeingt only hypercardiod mic , but the price seems odd to me for a K47 Capsule,
Dan,

I would say it's the other way around, sort of.
In any case the number 49 alone would indicate two sides active, because of all the patterns in an M49.

Last I heard the double sided capsule was called K47/49 and the single sided one K47fet.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on March 04, 2015, 09:44:56 AM
And if I can't connect pcb to chassis via screws..
can I  connect XLR pin1 to chassis via the XLR connector himself and connect pcb ground to XLR pin1 ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 04, 2015, 09:51:48 AM
Neumann returned my call today with pricing for what I asked for in the K47 capsule.

Their response was part #514753 at a cost of $587.86 USD.... but the message was choppy and I'm not even sure she understood clearly what part I was asking for.


I also didn't realize that the rear diaphragm wasn't sputtered?  That kind of kills the idea I had but would still be viable for this kit.

the Capsule that is not Sputtered on 1 side should be the K49 capsule , Since one of the side did not meet the machining spec for gaping distance for the backplate it is not sputtered , this is the capsule you will find in a tlm49 and style,
a K47 capsule should be on both side 100% sure,  in the case of the K49 it is a perfect match for this project beeingt only hypercardiod mic , but the price seems odd to me for a K47 Capsule,
Dan,

I would say it's the other way around, sort of.
In any case the number 49 alone would indicate two sides active, because of all the patterns in an M49.

Last I heard the double sided capsule was called K47/49 and the single sided one K47fet.

I had actually a neumann capsule for reskin here, Yes I do Reskin here but not for the public yet but it is coming.... the box was labelled K49 capsule and the backside was not sputtered,
well,  maybe that was the box but this is how i undestand it.  Gold rules...... :)
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 04, 2015, 09:54:08 AM
And if I can't connect pcb to chassis via screws..
can I  connect XLR pin1 to chassis via the XLR connector himself and connect pcb ground to XLR pin1 ?

Yes you can ,
Best,
DAn,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on March 04, 2015, 09:56:04 AM
But in this case I should make sure there's no contact of the pcb to the chassis right?
(I know, it sounds stupid, but.. you know what it is ...)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 04, 2015, 10:12:37 AM
But in this case I should make sure there's no contact of the pcb to the chassis right?
(I know, it sounds stupid, but.. you know what it is ...)

Dont worry about the ground loop for now as the  , it is another topics,
just hooked it up and start from there, the essence here is that the mic chassis acts as a " star groud point"
best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on March 08, 2015, 01:10:56 PM
You make me doubt !

I need to connect the XLR ground connector to the chassis or on the GND pad on the PCB?  'Cause the PCB are in contact with the body with the screws... I'm lost

And I have an another question : The turret connect some components to the ground, but the turret don't touch the PCB because of the white protection... It's normal?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 09, 2015, 10:40:02 AM
You make me doubt !

I need to connect the XLR ground connector to the chassis or on the GND pad on the PCB?  'Cause the PCB are in contact with the body with the screws... I'm lost

usually the xlr connector pin 1 goes to pcb xlr pad , so you will ground it from there

And I have an another question : The turret connect some components to the ground, but the turret don't touch the PCB because of the white protection... It's normal?
it does not connect to ground it the turrets serves a support to isolate the pcb from those connection but they are part of the circuit ,


Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on March 17, 2015, 05:22:59 PM
That's my built (in progress) I waiting wires from Chunger :

The capsule RK7 from Microphone-parts and the T.Bone SCT700 used for Donor Body

(https://lh3.googleusercontent.com/-FhDAuuXbG8o/VP9tY6gR5ZI/AAAAAAAAGpE/3RXLYNwkH28/w339-h452-no/11.jpg) (https://lh3.googleusercontent.com/-WBCsV6OFU7w/VP9tVJbMslI/AAAAAAAAGo8/qSA1NS8NZ8c/w339-h452-no/13.jpg)

Both side

(https://lh6.googleusercontent.com/-8ESwSkbQlxU/VQiUNmSzuJI/AAAAAAAAGyA/-fhtqhwREAQ/w339-h452-no/23.jpg) (https://lh4.googleusercontent.com/-lvXz0CPQbW0/VQiUNky5BAI/AAAAAAAAGx8/ymzQNeBr_lk/w339-h452-no/24.jpg)

The headbasket before and after

(https://lh6.googleusercontent.com/-WrhhlntaKHs/VP9uRRw4biI/AAAAAAAAGqI/OUgXHxuFWRs/w452-h339-no/gtrhrthr.jpg)

Previous capsule and Tube PCB

(https://lh6.googleusercontent.com/-gD2-HHXgd8o/VP9uC2qgSiI/AAAAAAAAGps/59ybrlbka8s/w339-h452-no/19.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: notlenny2 on April 03, 2015, 06:44:10 PM
Hey guys, this is a great forum!  Very helpful for a novice like myself.  I'm currently at the end of this build and I'm running into a problem with my Sowter 1303 F transformer.  The color code isnt lining up with the PCB color code and I can not for life of me find a chart for it.  The colors coming off of my transformer are Green Blue Brown Black and Grey, any idea how they correspond to the PCB?

Thanks for all the help, hope I can push this across the finish line!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TLRT on April 05, 2015, 06:00:03 AM
Hey guys, this is a great forum!  Very helpful for a novice like myself.  I'm currently at the end of this build and I'm running into a problem with my Sowter 1303 F transformer.  The color code isnt lining up with the PCB color code and I can not for life of me find a chart for it.  The colors coming off of my transformer are Green Blue Brown Black and Grey, any idea how they correspond to the PCB?

Thanks for all the help, hope I can push this across the finish line!

My PCB - sowter connections are:

BL - brown
VI - grey
BR - green
RT - blue
Ground - black

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: notlenny2 on April 06, 2015, 04:36:58 PM
Thanks!  I wired it up and I have zero sound though.  I'm sure its through something i did wrong.  I'm just not quite sure how to go about finding the problem.  Pretty much in over my head at this point.  Any insight one where to start testing would be greatly appreciated!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on April 07, 2015, 05:31:14 PM
How I do to place the jumpers for have -10dB?

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on April 11, 2015, 10:22:04 AM
That's mine ! Finished  :D

(Click on for enlarge)
(http://i19.servimg.com/u/f19/11/18/97/34/th/3510.jpg) (http://www.servimg.com/view/11189734/533)   (http://i19.servimg.com/u/f19/11/18/97/34/th/3310.jpg) (http://www.servimg.com/view/11189734/534)


Video test :)
https://www.youtube.com/watch?v=AMtOxiP0LBI (https://www.youtube.com/watch?v=AMtOxiP0LBI)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 11, 2015, 11:13:01 AM
That's mine ! Finished  :D

(Click on for enlarge)
(http://i19.servimg.com/u/f19/11/18/97/34/th/3510.jpg) (http://www.servimg.com/view/11189734/533)   (http://i19.servimg.com/u/f19/11/18/97/34/th/3310.jpg) (http://www.servimg.com/view/11189734/534)


Video test :)
https://www.youtube.com/watch?v=AMtOxiP0LBI (https://www.youtube.com/watch?v=AMtOxiP0LBI)

Yeah,  I really Enjoyed the Vid and the sound of the Axe.
Thanks for posting  8)
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: afdobbert on April 11, 2015, 07:25:08 PM
Here's another happy build! It sounds so nice, I had to do a quick test. Once I'm back from vacation in a week, I'll record another little sample at my studio, so we can hear it through my REDD pre clone and other fun things.

Here's a quick test I recorded at my apartment, just through an apollo twin and with me playing my crappy student model acoustic I usually just use for songwriting.  The mic made the acoustic sound much more expensive, I think  :)

https://soundcloud.com/alex-dobbert/fet-47-test-1?hc_location=ufi
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 11, 2015, 09:25:23 PM
Here's another happy build! It sounds so nice, I had to do a quick test. Once I'm back from vacation in a week, I'll record another little sample at my studio, so we can hear it through my REDD pre clone and other fun things.

Here's a quick test I recorded at my apartment, just through an apollo twin and with me playing my crappy student model acoustic I usually just use for songwriting.  The mic made the acoustic sound much more expensive, I think  :)

https://soundcloud.com/alex-dobbert/fet-47-test-1?hc_location=ufi

Very Nice sounding Voice your have there  8),  let us know how you make out,
Thanks For posting ,
Best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: acdc-angus on April 12, 2015, 06:29:53 PM
That's mine ! Finished  :D

(Click on for enlarge)
(http://i19.servimg.com/u/f19/11/18/97/34/th/3510.jpg) (http://www.servimg.com/view/11189734/533)   (http://i19.servimg.com/u/f19/11/18/97/34/th/3310.jpg) (http://www.servimg.com/view/11189734/534)


Video test :)
https://www.youtube.com/watch?v=AMtOxiP0LBI (https://www.youtube.com/watch?v=AMtOxiP0LBI)

Yeah,  I really Enjoyed the Vid and the sound of the Axe.
Thanks for posting  8)
Best,
Dan,
Thanks to you Dan, for the help  ;)

And an another one, the last posted on GroupDiy. Follow me for more:

https://www.youtube.com/watch?v=8UCZnPqavQ8

Good luck for the rest, see ya everyone ;D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: deveng on April 14, 2015, 12:05:05 PM
KasperNyhus

I like your custom L mic mount for the U47Fet.  Where did you find the mic stand adapter part for it?   Is the L made of stainless?

Regards,
Jeff
Title: Re: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on April 17, 2015, 06:39:48 PM
Make sure your link A to F are Solid continuity , that might be your problem here [...]
Hope this helps,
Dan,

Hey Dany.  My second U47FET build, I'm having a problem.  VERY VERY low output.  Have to crank the gain on the mixer ALL the way up to hear any signal.  Quite a while back in these posts, I found something you had written (above).  So this means I should have solid continuity between PCB transformer pin 1 (T-49 "A") and ground?  I don't, so could this be the issue?  I'm quite confused.

I'm using your T-49 PCB.  The AMI T-49 transformer measurements: A-B (primary) reads 675 ohms.  C-D (secondary) reads 18.8 ohms.  Looks right to me.

  Jimi Ray

******UPDATE - I removed the trim pot, bridged the connection and replaced R6 with the 6.8k resistor.  I also touched on all the solder joints with my iron.  The mic is now working fine.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on April 20, 2015, 05:00:25 PM
Here's a vocal test done with the first D-47FET kit I built.   Thanks Dany :)

I used Marvin Gaye's actual multitracks for "I Heard It Through The Grapevine" and had my singer layer a new lead vocal over it:

https://dl.dropboxusercontent.com/u/47755719/JaneyB-Motown/05%20I%20Heard%20It%20Through%20The%20Grapevine%20%28RS2-150322%29.mp3
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on April 20, 2015, 08:47:19 PM
  Just finished ours..
Thiersch red line M7, cinemag 13101, body from Ruud, it was really difficult to assemble but I don't regret.
So here is the armature I've built with screws and epoxy :
(http://img11.hostingpics.net/thumbs/mini_678277874.jpg) (http://www.hostingpics.net/viewer.php?id=678277874.jpg) (http://img11.hostingpics.net/thumbs/mini_247417393.jpg) (http://www.hostingpics.net/viewer.php?id=247417393.jpg) (http://img11.hostingpics.net/thumbs/mini_822464532.jpg) (http://www.hostingpics.net/viewer.php?id=822464532.jpg) (http://img11.hostingpics.net/thumbs/mini_678611421.jpg) (http://www.hostingpics.net/viewer.php?id=678611421.jpg)



  You can also see the capsule holder I've made with a 3cm  aluminium tube slice someone cut for me..
Here is the XLR and some kind of structure to hold the transformer, and also a small pcb I've added for the LC and Pad switches :
(http://img11.hostingpics.net/thumbs/mini_872402495.jpg) (http://www.hostingpics.net/viewer.php?id=872402495.jpg)  (http://img11.hostingpics.net/thumbs/mini_570398276.jpg) (http://www.hostingpics.net/viewer.php?id=570398276.jpg)

Then the pcb and the transformer :
(http://img11.hostingpics.net/thumbs/mini_195914277.jpg) (http://www.hostingpics.net/viewer.php?id=195914277.jpg)  (http://img11.hostingpics.net/thumbs/mini_556153648.jpg) (http://www.hostingpics.net/viewer.php?id=556153648.jpg)

Then I just have to put the capsule and to put the mic inside the body, I've drilled 2 holes to access the switches :
(http://img11.hostingpics.net/thumbs/mini_232724769.jpg) (http://www.hostingpics.net/viewer.php?id=232724769.jpg)

The mesh (I bought on ebay some great stainless steel mesh sheets) :
(http://img11.hostingpics.net/thumbs/mini_7687898510.jpg) (http://www.hostingpics.net/viewer.php?id=7687898510.jpg)  (http://img11.hostingpics.net/thumbs/mini_6091653811.jpg) (http://www.hostingpics.net/viewer.php?id=6091653811.jpg)

Some polish and that's it :
(http://img11.hostingpics.net/thumbs/mini_6859465413.jpg) (http://www.hostingpics.net/viewer.php?id=6859465413.jpg)

(http://img11.hostingpics.net/pics/6061339612.jpg)

  It's a very nice fet U47 in a kind of C12 body and last but not least, it sounds great!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 20, 2015, 08:53:09 PM
  Just finished ours..
Thiersch red line M7, cinemag 13101, body from Ruud, it was really difficult to assemble but I don't regret.
So here is the armature I've built with screws and epoxy :
(http://img11.hostingpics.net/thumbs/mini_678277874.jpg) (http://www.hostingpics.net/viewer.php?id=678277874.jpg) (http://img11.hostingpics.net/thumbs/mini_247417393.jpg) (http://www.hostingpics.net/viewer.php?id=247417393.jpg) (http://img11.hostingpics.net/thumbs/mini_822464532.jpg) (http://www.hostingpics.net/viewer.php?id=822464532.jpg) (http://img11.hostingpics.net/thumbs/mini_678611421.jpg) (http://www.hostingpics.net/viewer.php?id=678611421.jpg)



  You can also see the capsule holder I've made with a 3cm  aluminium tube slice someone cut for me..
Here is the XLR and some kind of structure to hold the transformer, and also a small pcb I've added for the LC and Pad switches :
(http://img11.hostingpics.net/thumbs/mini_872402495.jpg) (http://www.hostingpics.net/viewer.php?id=872402495.jpg)  (http://img11.hostingpics.net/thumbs/mini_570398276.jpg) (http://www.hostingpics.net/viewer.php?id=570398276.jpg)

Then the pcb and the transformer :
(http://img11.hostingpics.net/thumbs/mini_195914277.jpg) (http://www.hostingpics.net/viewer.php?id=195914277.jpg)  (http://img11.hostingpics.net/thumbs/mini_556153648.jpg) (http://www.hostingpics.net/viewer.php?id=556153648.jpg)

Then I just have to put the capsule and to put the mic inside the body, I've drilled 2 holes to access the switches :
(http://img11.hostingpics.net/thumbs/mini_232724769.jpg) (http://www.hostingpics.net/viewer.php?id=232724769.jpg)

The mesh (I bought on ebay some great stainless steel mesh sheets) :
(http://img11.hostingpics.net/thumbs/mini_7687898510.jpg) (http://www.hostingpics.net/viewer.php?id=7687898510.jpg)  (http://img11.hostingpics.net/thumbs/mini_6091653811.jpg) (http://www.hostingpics.net/viewer.php?id=6091653811.jpg)

Some polish and that's it :
(http://img11.hostingpics.net/thumbs/mini_6859465413.jpg) (http://www.hostingpics.net/viewer.php?id=6859465413.jpg)

(http://img11.hostingpics.net/pics/6061339612.jpg)

  It's a very nice fet U47 in a kind of C12 body and last but not least, it sounds great!


DIY at its best , Love it , thanks for posting ,
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on April 21, 2015, 05:14:13 AM
Very impressive work, saint gillis, you clearly put a lot of effort into this!

It looks great and has a look of its own. I like it a lot!

How did you do the markings on the body, I mean the cardioid mark and text etc? Screen printing?
And did you put some clear cote over it?

I have been wondering about good ways to mark metal, such as the PSUs for instance, without the need for badges.
This looks like just the way to do it!

//Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on April 21, 2015, 06:58:02 AM
Thank you Michael!
I used waterslide decals from Musikding, printed reverse, and put some spray matt varnish over it, at first it really looked like sh*t as there was some uggly drops over the body which had to stay right, but when it dried it was perfect..
I use this technic for frontpanels also, I failed several times before getting the right way to do it, and I still fail time to time, after putting the waterslide decals you can put your mic body/frontpanel at the oven  (progressive rise to 90°, ~3mins). If you have painted it you have to find the right varnish which goes with your paint, some might interact badly, and never put 2 layers, just one!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: mgronroos on April 21, 2015, 02:51:06 PM
Thanks for the info, saint gillis!

I will try the waterslides, I haven't done that since I built models as a kid..  :D

//Michael
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rlucas41 on April 28, 2015, 11:43:16 AM
Howdy folks, this is my first post in this thread and my first mic build too... Just needing a bit of guidance and clarification... I used the Cinemag 13101 transformer and have hooked it up (left to right) yellow, orange, brown, red. Needing to verify this is correct... Also what do I do with the black (center tap?) wire? I have terminated at this time and just left it alone. I'm getting good sound through the mic though I may have wired the xlr out of phase cause it sounds a bit thin... Also could I get some jumper clarification? The two prong jumpe (LC I think) does that control something beside activating the phantom power because if I don't have that jumper installed the mic goes dead? The two 3prong jumpers are for padding correct? I have experimented with them and found the best level for my RME Fireface but just want to be clear on their defined functions.  I've been reading through the posts and just needed some extra help please. Very excited about the mic and have already ordered my second PCB for another U47 FET from Poctop... Oh and I used a capsule from MicAndMod the vintage 47 capsule. Thanks for the help!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on April 28, 2015, 11:51:01 AM
I believe the CM-13101 connections should be:
brown - pad 1
red - pad 2
yellow - pad 3
orange - pad 4
black - glink
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rlucas41 on April 28, 2015, 11:56:28 AM
Hi Jimi,
Thanks for the fast reply, I will rewire and see how that sounds! I'm actually at the airport right now flying out for a couple week gig but am excited about his build! What capsule(s) have you used?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on April 28, 2015, 12:04:55 PM
I've built three of the D-U47FET's.  I put an Advanced Audio AK47 in the 1st, a Peluso P-K47 in the second, and a Microphone-Parts RK-7 in the third (not yet finished building).  I used AMI's T49 transformer in all three.  There is a sound clip above somewhere with the first build.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on April 30, 2015, 07:22:00 AM
Hi,
My mic sounds really great, but time to time I ve got a small amount of a kind of red noise appearing, it is an intermittent problem, do you have an idea about why? (the capsule..?)
..
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 30, 2015, 07:55:57 AM
i would definively check you HZ section at the Fet on the isolation pin  for cold solder ,
reheat this part if anything ,
hope this helps,
BEst,
DAn,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on April 30, 2015, 10:33:49 PM
It looked quite solid.. but sure I will check it carefully! thank you for this advice..
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on May 10, 2015, 10:32:47 AM
Hi again, so I re-soldered  the Hi-Z spot..
But then I had some big hum, I realised I made a ground loop when mounting back the body, so I fixed it, now it's good but I have a new problem, after 5 or 10s, the sound dissappears completely... I checked the voltages :
http://hpics.li/a97737e (http://hpics.li/a97737e)
A strange 44,6v instead of 21,5v at B point... Any idea about what's going on?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 11, 2015, 11:46:35 AM
Hi again, so I re-soldered  the Hi-Z spot..
But then I had some big hum, I realised I made a ground loop when mounting back the body, so I fixed it, now it's good but I have a new problem, after 5 or 10s, the sound dissappears completely... I checked the voltages :
http://hpics.li/a97737e (http://hpics.li/a97737e)
A strange 44,6v instead of 21,5v at B point... Any idea about what's going on?

what is the configuration of the 220M resistor is it 200 + 20 or 220M and if it is 220M only did you solder to no r+ pad as described in the build.
send a picture of this section , 
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on May 11, 2015, 12:48:23 PM
what is the configuration of the 220M resistor is it 200 + 20 or 220M and if it is 220M only did you solder to no r+ pad as described in the build.
send a picture of this section , 
Best,
Dan,
Damn not... I solder the 220M to the wrong hole...
I'm corecting that... Do you think it could have damaged something?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on May 11, 2015, 01:13:25 PM
Ok I soldered the 220M resistor properly , but I still have the pbm of the sound switching off after 10s...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 11, 2015, 01:38:02 PM
Ok I soldered the 220M resistor properly , but I still have the pbm of the sound switching off after 10s...

remove capsule and inject sine tone in the amp just before the fet coupling cap ,  2200pf IIRC,
this will rule out the capsule for contamination , and recheck voltage ,
Check for cold solder in the HZ bridge,
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on May 11, 2015, 02:19:13 PM
remove capsule and inject sine tone in the amp just before the fet coupling cap ,  2200pf IIRC,
this will rule out the capsule for contamination , and recheck voltage ,
Check for cold solder in the HZ bridge,
Best,
Dan,
Ok, did what you said, so same voltages, and still same 44,6V at "B" point...
And concerning collector of T4 it takes about 20s on the voltmeter from 38v untill it reaches the voltage of 26,9V... (it was the same last time but I did not mention it) ...
Thanks for helping Dany!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 11, 2015, 07:04:01 PM
remove capsule and inject sine tone in the amp just before the fet coupling cap ,  2200pf IIRC,
this will rule out the capsule for contamination , and recheck voltage ,
Check for cold solder in the HZ bridge,
Best,
Dan,
Ok, did what you said, so same voltages, and still same 44,6V at "B" point...
And concerning collector of T4 it takes about 20s on the voltmeter from 38v untill it reaches the voltage of 26,9V... (it was the same last time but I did not mention it) ...
Thanks for helping Dany!

if you missed this , I would suggest you check out the build guide just to make sure you haven't made a mistake with the lwire ink on both pcb,  check for leaky cap around T4 ,  and potentiometer configuration if you haven't used it or installed it ,
reverify transistor number and position ,
Hope this helps,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on May 12, 2015, 04:52:55 PM
Hi Dany,
So I'm an asshole for many reasons..
1st of all for having said the mic sounded great, because now that everything's ok it 's nothing compared than before, it's f**king amazing!
I replaced C7 & C8, but it changed nothing, then I changed all the bipolar transistors, it's not the way I like to fix stuff, but I lost patience... and now I discovered an amazing microphone, awesome!!!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Biasrocks on May 12, 2015, 09:47:57 PM
Project complete.

Badaax GT-2B for donor
RK47 Capsule
Cinemag Transformer

Easily completed in about 3 hours, powered up and worked from the hop.

Mark

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Biasrocks on May 12, 2015, 09:48:52 PM
Another shot.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Biasrocks on May 12, 2015, 09:50:03 PM
Another shot.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Biasrocks on May 12, 2015, 09:52:06 PM
One more.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Biasrocks on May 14, 2015, 12:23:43 PM
Here's a quick drum recording I did to showcase what the 47FET brings to the party.

Photo's

https://www.dropbox.com/s/szj92zha84vwz6q/IMG_0991.JPG?dl=0
https://www.dropbox.com/s/gu56yqu96whrp1x/IMG_0992.JPG?dl=0

Audio 24/88kHz, RE20, U47FET Kick, SM57 Snare, U87 Overheads,
No EQ or processing aside from some parallel compression.

Full kit w/47FET
https://www.dropbox.com/s/1hvhmnk897chd4x/Drums-U47FET-All.wav?dl=0

Full kit wo/47FET
https://www.dropbox.com/s/inaqlkg8wtavv87/Drums-U47FET-Off.wav?dl=0

47FET  Solo
https://www.dropbox.com/s/bxjp19z3qtia3nv/Drums-U47FET-Solo.wav?dl=0

RE20 Solo - Inside Kick
https://www.dropbox.com/s/95b1n3i6r8syt9j/Drums-RE20-Solo.wav?dl=0

RE20 47FET Combined
https://www.dropbox.com/s/eiyxhv9b89m3w5v/Drums-RE20-U47FET-Solo.wav?dl=0

FULL KIT Processed
https://www.dropbox.com/s/gt7hfsi5ex7ie46/Drums-Processed.wav?dl=0

Mark
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Matt55 on May 27, 2015, 11:01:00 AM
Hello Dany,

So I have just started populating the board and realised Mouser made a cock up on my order and missed some of the parts out of the BOM!

I have ordered the parts that were missing so I am waiting for them, not a problem as I uave my U87 to be finishing off.

I have a few questions regarding the build;

1) I noticed there are many additional parts for BC5578 and BC5478. What is the aim here? Do i need to measure them like the JFET in the U87 build and pick a certain on based on their measurements? Should they be as similar as possible etc??

2) Resistors (R18+R19) and (R20+R21) also have additional parts. Do these need to be matched within a certain percetage like the ones in the u87 build? I can use a wheatstone bridge like i did there if thats what they need? What percentage do they need to be matched to?

3) On the schematic the Styrene at C2 reads 18pf, the one from you has 20K printed on it? Is this ok?

4) On the schematic R5+ and R5 suggest 33M or 2x68M, the one in the BOM is 30M. Is this ok?

Thanks for creating these builds they are quite marvelous :) I cant wait to get both my U87 and U47FET working and in use in my studio :)

Regards,

  Matt
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 28, 2015, 08:25:46 AM
Hello Dany,

So I have just started populating the board and realised Mouser made a cock up on my order and missed some of the parts out of the BOM!

I have ordered the parts that were missing so I am waiting for them, not a problem as I uave my U87 to be finishing off.

I have a few questions regarding the build;

1) I noticed there are many additional parts for BC5578 and BC5478. What is the aim here? Do i need to measure them like the JFET in the U87 build and pick a certain on based on their measurements? Should they be as similar as possible etc??

normally you would check for highest HFE on these but they are already garanteed , so keep those as spare as those fairchild transisitor wont be here for muc much longer

2) Resistors (R18+R19) and (R20+R21) also have additional parts. Do these need to be matched within a certain percetage like the ones in the u87 build? I can use a wheatstone bridge like i did there if thats what they need? What percentage do they need to be matched to?
0.4%

3) On the schematic the Styrene at C2 reads 18pf, the one from you has 20K printed on it? Is this ok?
yes it is ok it is 20pf with 10% tolerance  =  20K

4) On the schematic R5+ and R5 suggest 33M or 2x68M, the one in the BOM is 30M. Is this ok?
if you have R5 at 30M this is ok use only R5  if you have 2*68M then use R5 and R5+ as they are in parralele

Thanks for creating these builds they are quite marvelous :) I cant wait to get both my U87 and U47FET working and in use in my studio :)

Regards,

  Matt
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on May 28, 2015, 08:28:26 AM
Hi Dany,
So I'm an asshole for many reasons..
1st of all for having said the mic sounded great, because now that everything's ok it 's nothing compared than before, it's f**king amazing!
I replaced C7 & C8, but it changed nothing, then I changed all the bipolar transistors, it's not the way I like to fix stuff, but I lost patience... and now I discovered an amazing microphone, awesome!!!

dont worry your not.....  :).  everybody make mistake and this is where you learned the most when
i will have now to like your post for the second part of it , Thanks for posting ,
Best,
dAn,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: roger.unc on June 27, 2015, 08:48:54 PM
Hi - I've just "completed" my build of the U47FET. The mic passes audio but cuts out at regular intervals every few seconds. I injected continuous white noise into my amp and recorded the result with the mic - dropbox link below. I've also attached a picture of the waveform. Any ideas on what could be causing this? Bad styroflex caps? Thanks. --Roger

https://www.dropbox.com/s/y3yvmas35iub89o/u47FET_test.mp3?dl=0
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on June 27, 2015, 10:15:12 PM
Hi - I've just "completed" my build of the U47FET. The mic passes audio but cuts out at regular intervals every few seconds. I injected continuous white noise into my amp and recorded the result with the mic - dropbox link below. I've also attached a picture of the waveform. Any ideas on what could be causing this? Bad styroflex caps? Thanks. --Roger

https://www.dropbox.com/s/y3yvmas35iub89o/u47FET_test.mp3?dl=0

you probably solder the HZ resistor in the wrong pad , No R+ pad is using the 220M resistor ,
(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d0281994680.jpg)
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: roger.unc on June 27, 2015, 10:55:05 PM
Bingo! I did not solder the correct pad for the 220. Funny how I can read the directions, look at the picture, and still not understand how it's supposed to be done. Many thanks! The mic sounds great.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: plinker on July 28, 2015, 11:10:27 AM
Hey folks,

Has anyone measured the noise performance on this build?  I realize it's the same circuit as the original Neumann product, but with all the low noise components available now I'm curious how it compares.

Thanks,
Jim
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rlucas41 on July 29, 2015, 08:07:31 PM
Hello folks,
 I wanted to post a picture and sound clip of my U47fet... what a great mic this is! I have built two of them now both with the Cinemag MM13101 transformer and the MicAndMod vintage 47 capsule...
The clip is of an acoustic guitar track I did with a Gibson J45>U47fet>Redd 47>RS124>RME Fireface 800

https://www.dropbox.com/s/wfcpbvmfqoofzi3/Berts%20Acoustic%20guitar_05.wav?dl=0
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on August 31, 2015, 07:41:32 AM
My 4th U47FET build.   MXL V89 donor body, MP RK-47 capsule, Cinemag CM-13101 transformer...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on August 31, 2015, 07:42:11 AM
This shows the modifications to the inner rails and the assembled mic...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TLRT on August 31, 2015, 02:15:17 PM
Drum OH's / acoustic guitars / vocals were all recorded with my u47fet clones, band was number one in the local radio charts:

https://www.youtube.com/watch?v=VnlMOa-GiXA
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on August 31, 2015, 02:19:57 PM
Drum OH's / acoustic guitars / vocalls were recorded with my u47fet clones, band was number one in the local radio charts:

https://www.youtube.com/watch?v=VnlMOa-GiXA

Aweseome,
Best,
DAn,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on September 30, 2015, 05:49:48 AM
Hey guys,

Been a while since I've been asking these parts. I built me U47 FET probably over a year ago now and while I love the sound it is soooooo noisy so it's almost impossible to use. Anyone else have noise issues?

I took plenty of care building it. Constantly cleaning with alcohol. Could I have a dud FET? Or could it be a bias problem? I used a jumper instead of a trimmer because I don't have a scope.

Cheers,

Kris
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tmuikku on September 30, 2015, 06:43:44 AM
Hey guys,

Been a while since I've been asking these parts. I built me U47 FET probably over a year ago now and while I love the sound it is soooooo noisy so it's almost impossible to use. Anyone else have noise issues?

I took plenty of care building it. Constantly cleaning with alcohol. Could I have a dud FET? Or could it be a bias problem? I used a jumper instead of a trimmer because I don't have a scope.

Cheers,

Kris

is mic enclosure grounded and to xlr pin 1 only? i haven't built this mic yet but this is crucial on most i believe.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on September 30, 2015, 08:05:00 AM
is mic enclosure grounded and to xlr pin 1 only? i haven't built this mic yet but this is crucial on most i believe.

Yep
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Enchilada on October 26, 2015, 09:49:25 AM
I'm way too lazy to troubleshoot these days. I just ordered a new PCB, hammered out a soldering session and now it's all good  ;D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Andriejus on November 12, 2015, 02:42:19 AM
I have the same issue. It sounds nice but a lot of ocean noise.
Can I clean pcbs with components in ultrasonic bath with water?

Where did you use a jumper? I used no trimmer and no jumper, maybe there is a problem? :D

Kind regards,
Andrew
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: saint gillis on November 12, 2015, 09:56:27 AM
I have the same issue. It sounds nice but a lot of ocean noise.

Hello, I also had the same issue, so as Dany advised me I cleaned around A B C D E F points, and I also cleaned everywhere high value resistors were involved and around the high-Z zone, I also dug a bit with a cutter and a small screwdriver between the traces involved to make sure the isolation was optimum because my pcb was kind of really dirty... and now the mic sounds perfect...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: lp1000 on November 30, 2015, 06:55:48 AM
Hello,

I use a capacitor 18pF and 33pF / 4000V instead 18pf and 33pF / 630 V, it will affect the sound?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: deveng on November 30, 2015, 07:40:44 PM
Just finished up my U47FET clone today.   Worked first power up and is nice and quiet.   I used the GT-2B donor body from Chunger,
a Cinemag 13101 and a Equinox Q47D I got from Skylar quite awhile back.   I've got a 10 song tracking session starting this week and it will make its debut as outside kick.   I was going to use the Q47D for a second MK47 but decided this mic would be a good use of the capsule (will go with either a Beesneez M7 or Thiersch for my second MK47).   

Thanks to Poctop for the kit!  Easy and fun build with great results.

Next mic on the list will be a pair of  U67's.

regards,
Jeff
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on November 30, 2015, 07:51:56 PM
Just finished up my U47FET clone today.   Worked first power up and is nice and quiet.   I used the GT-2B donor body from Chunger,
a Cinemag 13101 and a Equinox Q47D I got from Skylar quite awhile back.   I've got a 10 song tracking session starting this week and it will make its debut as outside kick.   I was going to use the Q47D for a second MK47 but decided this mic would be a good use of the capsule (will go with either a Beesneez M7 or Thiersch for my second MK47).   

Thanks to Poctop for the kit!  Easy and fun build with great results.

Next mic on the list will be a pair of  U67's.

regards,
Jeff

Thanks Jeff for the Nice word always glad to hear those Stories,

regarding the M7 you should check out my New D7 Capsule here

http://www.vintagemicrophonepcbkit.com/Caspsule.html

this is my take on the M7 Capsule.
Let me know then,

Best,
Dan,

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: deveng on December 01, 2015, 10:22:07 AM
Dan,

Might just do that!  Price is significantly lower and the feedback appears to be all good for your D7.     

So far I've used a Peluso CEK12 (in a 251 recreation), a Charles/Ulan M7 in my first MK47 and now one of the Q47D's in the 47FET.   All sound really nice.    Still have the U67's to build as well and will need a pair of capsules for those.

Keep up the great work Dan,
Regards,
Jeff
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: deveng on December 04, 2015, 11:42:42 AM
I'm setting up a tracking session and while checking all mic connections/routing etc on the drums one of the first things I notice is how quiet this U47 FET is.    The self noise is much lower than most of the mics in my locker.   

Speaking of noise, I can't over emphasize for new builders the importance of clean PCB's.    This includes body oils as well as flux.  Especially in the high impedance sections.    Look closely at the solder pads and make sure no flux remains.  Sometimes its tough to get it all off and may take a good scrubbing to remove all the flux.   

Regards,
Jeff
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: deveng on December 06, 2015, 11:05:33 AM
Now have the first 2 tracks of drums using RE-20 inside kick and the U47-FET outside.  Its about 1 foot off the head and off center and it sounds very good.  I have to say, Skylar's (Equinox) Q47D capsule works quite well with this mic.   When I bought his MK47 kit, spare Equinox body and misc parts he tossed in the capsule as part of the deal.  I was blown away by his generosity.   Just want him to know that the capsule has found a good home and will get plenty use.

I'm very pleased with Dan's pcb kit. 

I've had the DIY disease for many years (building mostly discrete preamps) but my affliction has spread to input transducers!

Regards,
Jeff
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Biasrocks on December 14, 2015, 01:10:12 PM
My preferred combination on Kick drums as well.

The FET brings so much to the party.

Mark

Now have the first 2 tracks of drums using RE-20 inside kick and the U47-FET outside.  Its about 1 foot off the head and off center and it sounds very good.
Regards,
Jeff
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: nielsk on December 23, 2015, 07:36:19 PM
About to undertake a build, and today the search engine no worky...
Can someone save me searching every page and point me to a regular BOM (NOT a shopping cart) that covers everything and explains what the deal is with the Styro caps as it looks like it is all Wimas?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Zjcc56 on January 09, 2016, 01:38:03 PM
So I've built one of theses with the alctron GT-2B body and its killer!
the only problem is that the shock mount is nice but it makes it hard to get in to some places with the mic, does anyone know of just a screw on mount for this body? (non Shock Mount)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: andybaker28 on January 26, 2016, 12:33:02 PM
Finally Received a Short U47 FET Prototype Body From Oliver At AMI ,

i have sent the mic to higher authorities to get it evaluated, So Far So Good,

I should hear back soon,

Best,
DAn,

Hi Dan,

I just assembled the round pcb version of the Fet 47 that got from you last week. I am not getting any output as of yet, so just starting to trouble shoot. I wanted to ask a couple of things. I am using a 9.5/1 transformer that I got from 3U audio, and I have it connected red-1 brown-2 orange-3 and yellow-4.  I am not sure if this is correct. I have attached a schematic I was sent from them. The other question is that I noticed the jumpers are this version in the photo, it is my understanding that without these on the mic is without any pad and or low cut. Is that correct?

I will double check all the connections and voltages next! It was a fun build and I am excited to get this one sorted out.

here is a link to the transformer on ebay..

http://www.ebay.com/itm/3U-Audio-GZT-87-Output-Transformer-for-Condenser-Microphone-/111683319855?hash=item1a00d8382f:g:f6kAAOSwiCRUg89Z

thanks much!

 
Oliver Archut U47Fet Short Body Prototype

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00168.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00169.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00170.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00171.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00172.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00173.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00174.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00175.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00176.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00177.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on January 26, 2016, 07:26:30 PM
Finally Received a Short U47 FET Prototype Body From Oliver At AMI ,

i have sent the mic to higher authorities to get it evaluated, So Far So Good,

I should hear back soon,

Best,
DAn,

Hi Dan,

I just assembled the round pcb version of the Fet 47 that got from you last week. I am not getting any output as of yet, so just starting to trouble shoot. I wanted to ask a couple of things. I am using a 9.5/1 transformer that I got from 3U audio, and I have it connected red-1 brown-2 orange-3 and yellow-4.  I am not sure if this is correct. I have attached a schematic I was sent from them.

this is correct   
Quote
connected red-1 brown-2 orange-3 and yellow-4.

 The other question is that I noticed the jumpers are this version in the photo, it is my understanding that without these on the mic is without any pad and or low cut. Is that correct?

Correct
Make sure you have the backplate of the capsule connected to the pad where it says bck this is pad is gnd , so your backaplte should be grounded to mic chassis , if this is not the case you will have this issue,


I will double check all the connections and voltages next! It was a fun build and I am excited to get this one sorted out.

here is a link to the transformer on ebay..

http://www.ebay.com/itm/3U-Audio-GZT-87-Output-Transformer-for-Condenser-Microphone-/111683319855?hash=item1a00d8382f:g:f6kAAOSwiCRUg89Z

thanks much!

 
Oliver Archut U47Fet Short Body Prototype

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a08a52.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a08a63.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a08a74.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a08a85.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a08a97.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d1402a08aa8.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00174.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00175.jpg)

(https://dl.dropboxusercontent.com/u/43869772/FET47%20aMI/DO-47FET/DO-47FET/CAM00176.jpg)

(https://io.groupdiy.com/file/gdiy-2017/u/39511/58d028199489e.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Haberdasher on February 17, 2016, 02:14:29 PM
Hello everyone, I'm here to report another success story.  This was my first diy mic, and I think I picked a great one.  I'm very happy to say it fired right up on the first try, and is very quiet.  We put it up against my sister's "good" mic and it blew it out of the water, so she is pretty excited.

I used the GT-2B body and a 47 type capsule from aliexpress, which sounds really good to me.  Cinemag 13101 for the xformer.

(http://s22.postimg.org/banxswdhd/Front.jpg)

(http://s22.postimg.org/5nrkvfayp/Guts1.jpg)

(http://s15.postimg.org/ndnr61863/Guts2.jpg)

I thought it might be helpful if I posted some notes I made while I was building.

- The GT-2B body doesn't come with screws for the pcb's.  These were perfect.  No affiliation.
http://www.ebay.com/itm/111607847719?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

- You don't need the screws or L-shape brackets on the Mouser BOM if you are using the square pcb's.

- If you are going to use the 30M resistor for R5, you really only need to order 1x 68M, not 3.

- The hole in the pcb is too small for the binding post on the Mouser BOM.  It would be better to dry fit that & drill it out a tad if necessary before population, because it's more difficult after there are components everywhere.

Thanks for the awesome project, it was a blast.  Now I kinda want to build another mic, haha. Too bad I'm broke!  ;)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on February 17, 2016, 02:27:10 PM
Congrats!

Build your next with an edge terminated capsule (CK12 type). That would be a great complement.  :P
And are you ready for tubes?

But for now, enjoy!


Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Haberdasher on February 17, 2016, 05:41:02 PM
Congrats!

Build your next with an edge terminated capsule (CK12 type). That would be a great complement.  :P
And are you ready for tubes?

But for now, enjoy!
Thanks!

Yes, I'd love to do something with a tube and a edge termed capsule but that's more of a long term project, I'm afraid.

A D87 is up next, because I have everything but the tapered circuit boards and the capsule.  ;D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on February 17, 2016, 05:55:51 PM
Nice one, too.
Come to think of it, it doesn't really matter which one is next.
In the end you'll want them all anyway.  ;)
Just take your time and work your way through all the D-models.  8)

Oh, and don't forget to use them!  ;D

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: nielsk on March 04, 2016, 09:26:31 AM
Finished some builds using Vintage Microphones D7 capsules, sounding great!
No problems at all, everything works perfect upon first fire up.
I did a few things that worked out well for me, first the transformer mount for the Cenimag:
I took a bit of plastic drywall J-bead, cut it to fit and bent in some sides, put some neoprene in to cushion and used tiny self tapping screws to secure it using the existing holes in the rails
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: nielsk on March 04, 2016, 09:26:58 AM
pic #2
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: nielsk on March 04, 2016, 09:28:53 AM
I also used micro-mini toggle switches right on the PCB for the PAD and FILTER, as I rarely use these on this mic it is no problem to remove the cover to switch them, works great:
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: crackerjack555 on April 11, 2016, 01:24:59 PM
Vinylwall,

 I see you used an Advanced Audio Ak47 capsule with your one of your mics.  Did you like it?  I'm shopping for a 47 capsule right now and preparing to start the D-47 project from http://www.vintagemicrophonepcbkit.com/D-47.html (http://www.vintagemicrophonepcbkit.com/D-47.html) .  Seems like the AK47 price is very reasonable. 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on April 11, 2016, 01:38:54 PM
Vinylwall,

 I see you used an Advanced Audio Ak47 capsule with your one of your mics.  Did you like it?  I'm shopping for a 47 capsule right now and preparing to start the D-47 project from http://www.vintagemicrophonepcbkit.com/D-47.html (http://www.vintagemicrophonepcbkit.com/D-47.html) .  Seems like the AK47 price is very reasonable.

I haven't been able to hear a noticeable difference between the Advanced Audio and Microphone Parts 47 capsules.  Both work equally good.  I have been using my U47fet builds almost exclusively on guitar cabinets.

FYI: here is something I posted a while back regarding some of the microphone builds I've done: http://groupdiy.com/index.php?topic=60417.msg766068#msg766068
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: crackerjack555 on April 11, 2016, 02:04:56 PM
Vinylwall,

 I see you used an Advanced Audio Ak47 capsule with your one of your mics.  Did you like it?  I'm shopping for a 47 capsule right now and preparing to start the D-47 project from http://www.vintagemicrophonepcbkit.com/D-47.html (http://www.vintagemicrophonepcbkit.com/D-47.html) .  Seems like the AK47 price is very reasonable.

I haven't been able to hear a noticeable difference between the Advanced Audio and Microphone Parts 47 capsules.  Both work equally good.  I have been using my U47fet builds almost exclusively on guitar cabinets.

FYI: here is something I posted a while back regarding some of the microphone builds I've done: http://groupdiy.com/index.php?topic=60417.msg766068#msg766068

That's great news because I just finished my first mic kit from microphone-parts.  It's the T-12 kit with Rk12 capsule and I LOVE it. Sounds better on vocals than our TLM103! I figure if a fet mic sounds THAT good, I have to try a tube mic (U47 clone of course!).

 I read your post and I am very impressed with your collection and building experience.  I see one of your builds was the D-47 that I want to build.  How do you like your D-47?  I saw it in your list, but you didn't mention it after that.

Thanks,

Troy
Auburn Hills, Michigan

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: vinylwall on April 11, 2016, 02:08:18 PM
Vinylwall,

 I see you used an Advanced Audio Ak47 capsule with your one of your mics.  Did you like it?  I'm shopping for a 47 capsule right now and preparing to start the D-47 project from http://www.vintagemicrophonepcbkit.com/D-47.html (http://www.vintagemicrophonepcbkit.com/D-47.html) .  Seems like the AK47 price is very reasonable.

I haven't been able to hear a noticeable difference between the Advanced Audio and Microphone Parts 47 capsules.  Both work equally good.  I have been using my U47fet builds almost exclusively on guitar cabinets.

FYI: here is something I posted a while back regarding some of the microphone builds I've done: http://groupdiy.com/index.php?topic=60417.msg766068#msg766068

That's great news because I just finished my first mic kit from microphone-parts.  It's the T-12 kit with Rk12 capsule and I LOVE it. Sounds better on vocals than our TLM103! I figure if a fet mic sounds THAT good, I have to try a tube mic (U47 clone of course!).

 I read your post and I am very impressed with your collection and building experience.  I see one of your builds was the D-47 that I want to build.  How do you like your D-47?  I saw it in your list, but you didn't mention it after that.

Thanks,

Troy
Auburn Hills, Michigan

I have a couple of the D-47 builds now.  I have been trying out one of them and like how it sounds on acoustic guitar.  Haven't recorded much else with it yet.

Here are some photos of one of the builds:  http://groupdiy.com/index.php?topic=58609.msg769203#msg769203
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: crackerjack555 on April 11, 2016, 02:40:43 PM
Very cool! Can't wait :D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on April 15, 2016, 02:08:21 PM
Dan, or anybody,
Any ideas what I might be dealing with here? My D-U47FET has worked fine for a few years. But now it has low output and is noisy.
Checking voltages, I get good readings at T7 and T5, and phantom power is 47V at XLR pins 2 and 3.
But, at T3 I get 43V at the collector, but only 29.5V at the Base (and positive side of C6), and I get 38V at the emitter.
I only get 21V at the positive side of C5. Other values in that area of the circuit are also incorrect.

I replaced T3 with a new one, but it didn't help.

Any ideas on where to look next?
Thanks,
JS
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: skidmorebay on April 17, 2016, 09:26:26 PM
Solved my problem - broken wire between the two PCB's (A to AA) . Back in business.
JS
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on April 19, 2016, 11:16:39 AM
Solved my problem - broken wire between the two PCB's (A to AA) . Back in business.
JS

Another one Down ,
 8)
Dan
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TLRT on April 25, 2016, 12:05:39 PM
Another "official" track, 47fet clone with Thiersch M7 capsule:

https://www.youtube.com/watch?v=c0KooOUYV7o&index=11&list=PLkaemF17IwDLnW4JyPK-n2RhjsmEqUhIv
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on April 25, 2016, 02:10:42 PM
Nice.  :)

How much treble lift?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TLRT on April 25, 2016, 03:12:13 PM
I wasn't there at the mixing,so I'm not sure, the raw version is pretty nice also.

Nice.  :)

How much treble lift?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: seancook on June 01, 2016, 10:07:03 AM
ive been tinkering away on a build here, hk47 capsule and cinemag transformer so looking forward to hearing it!

only problem is i haven't got it going yet.

triple checked my soldering and components but still no luck

at the moment i can get sound out of it (however thin) when i first switch on phantom but a few seconds later it cuts out and wont give me any more sound.... any thoughts?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: tskguy on June 01, 2016, 12:35:09 PM
You may want to make sure that you have the leg of R2 resistor in the top hole.. I messed that up once and if I recall had a similar issue.

Eric
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: seancook on June 01, 2016, 06:23:51 PM
yeh i have r2 going into the the no R+ hole
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: thegoldenrulers on June 19, 2016, 11:24:23 AM
Hi All,
I have 3 questions I am hoping someone can assist  :)
1) I exposed part of the trace on the pcb when pulling the 3.6 to add the 6.8 - Is this really, really bad? (Third solder point down from top left in photo)

2) I was going to jumper where the bias goes. Ok to just use the wire cutoff from the styrocap?

3) I have 3 mini jumpers, (2) 2c header, (1) 3c header, and 1 turret to pin leftover. Did I miss something??
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: thegoldenrulers on June 19, 2016, 11:25:25 AM
Image for question #2
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: thegoldenrulers on June 19, 2016, 11:26:06 AM
Image for Question #3
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TLRT on August 12, 2016, 08:55:45 AM
Which cap value should be changed if I want to reduce the highs? (9k area) the styro 33pf, or the 2200pf one?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: dchang0 on December 16, 2016, 01:37:09 PM
On the original Neumann schematic that has transformer U1, p/n 90 331, this is the wiring:

RT = pin 1 on U47fet PCB
BR = pin 2 on U47fet PCB
VI = pin 3 on U47fet PCB
BL = pin 4 on U47fet PCB
WS is shorted to WS*
GE is shorted to GN* (ignore switch S3)

Here are the wiring details I figured out for the AMI T49 transformer and poctop's T49 adapter PCB. I have confirmed the following to work properly in my own build.

See AMI's T49 schematic attached. On my transformers, A-B does measure at higher resistance on a multimeter--around 658 ohms. C-D does measure at lower resistance--around 15 ohms.

To read the chart, use this legend:
U47fet PCB pin => wire color => AMI T49 pin

1 => brown => A "capacitor"
2 => red => B "ground"
3 => yellow => D "xlr pin 3"
4 => orange => C "xlr pin 2"

The Cinemag CM-13101 wire colors are the same and should work, but I have not confirmed that the wiring is correct as above, as I do not own one.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: dchang0 on December 16, 2016, 01:43:26 PM
Next are the photos for the AMI T49 adapter PCB and how it is mounted in the GT-2B body. I had to drill and tap one hole in each rail to mount the board. My advice: don't bother using a tap. Use self-tapping M2 screws. The tap thread is so fine and the metal so mushy that it basically was useless.

The transformer is huge, so it is necessary to sandwich the rails between the PCB and the transformer.

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: dchang0 on December 16, 2016, 01:47:53 PM
Photo showing the rails sandwiched between the T49 and the adapter PCB:

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: dchang0 on December 16, 2016, 01:55:44 PM
Now on to a totally different topic:

I researched DPDT switches that would fit the 2x3 2.54mm x 2.54mm grid labeled "Pad" that is an optional replacement for the s1a and s1b 1x3 2.54mm male headers and found that the NKK "ultra-miniature" switches will work.

Of the NKK switch designs, their slide switch is the shortest vertically:

http://nkk.com/documents/products/illuminated_slide/ss/ssnonilluminated.pdf

The part number I chose is SS22SDP2 and is available at Mouser, Digikey, and Allied Electric.

For the 1x2 2.54mm male header labeled "LC (Low Cut)" there are two options for a switch:

1) Buy the SPDT NKK SS12SDP2 and cut one leg off. The body is somewhat large for the spot, so it will overlap onto the space for the trimmer (where the jumper is).

2) Erg Components makes an ingenious little slide switch with a tiny footprint exactly for the purpose of replacing 1x2 jumpers.

Allied Electric is the only USA carrier that stocks them so far, as Erg is a British company:

http://www.alliedelec.com/erg-jsa4-01-go/70746110/

Attached is the photo of the tiny NKK "ultra-miniature" switches. They fit perfectly. Given how much space is inside the GT-2B body, I could have ordered the 9mm tall ultra-miniature toggle or rocker switches that NKK also makes.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Vac11 on March 20, 2017, 10:09:14 AM
There are some resistors marked as 1/2W in BOM (6K8, 100K, 4K7, 470K, 47K....). Can I safely use 1/4W metal film resistors instead?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Vac11 on March 23, 2017, 08:32:16 AM
Bump...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on March 23, 2017, 08:37:56 AM
yes you can ,
D,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rixsta on May 21, 2017, 07:25:24 PM
Hey just a question

Are those yellow caps on the board of good quality or do they not matter so much ? also Is this a Class-A circuit ?
Im quite interested in making a U47 this one looks quite nice :)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rixsta on May 31, 2017, 07:47:40 AM
Hey all, Just wondering, can this mic be built for £500 ?

Thanks
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rixsta on June 04, 2017, 01:28:06 PM
Hello folks,
 I wanted to post a picture and sound clip of my U47fet... what a great mic this is! I have built two of them now both with the Cinemag MM13101 transformer and the MicAndMod vintage 47 capsule...
The clip is of an acoustic guitar track I did with a Gibson J45>U47fet>Redd 47>RS124>RME Fireface 800

https://www.dropbox.com/s/wfcpbvmfqoofzi3/Berts%20Acoustic%20guitar_05.wav?dl=0

Did you notice the noise in this recording ?
Its great sounding but theres a buzzing ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on June 09, 2017, 07:00:51 PM
short question,
will the thiersch capsule mount holder will fit a t-bone sct700 body, or is the holder to high ?
Maybe someone hast already experience with it.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rixsta on June 10, 2017, 08:39:08 AM
short question,
will the thiersch capsule mount holder will fit a t-bone sct700 body, or is the holder to high ?
Maybe someone hast already experience with it.

Thats what I wanted to know too, so looks like a Thiersch is suitable for this Fet47 mic then ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on June 10, 2017, 09:04:49 AM
You're in Europe (like Thiersch), but there's this new trade treaty between Canada and the EU. Britain is still in (and later on there may be a Commonwealth deal?). Anyway, our own Dany (maker of the D-U47fet PCB that this thread is about) makes an M7, too.

Also, the Canadian dollar is relatively cheap. As is the Aussie dollar BTW (BeesNeez K7). Ben and Veronica are members here, as well.

And while I'm at, Eric (HK47) is a fellow member, too. But he's in the US. FWIW.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rixsta on June 10, 2017, 04:06:37 PM
By the looks of it here on the forum that will work well with both this D-U47 Kit and the Valve U47 Kit from ioaudio
I hope so anyway :D

The thiersch capsule Im still not sure about so If anyone knows if their holder I can get working with the T-bone sct700 body, or that Alctron GT-2B  let us know, cheers!

micaddict
Cheers, Ive heard some samples by Chunger and I felt like I like the sound of Eric (HK47) and the Thiersch M7 most, Erics has more top end and Thierch M7 has more body and depth and I really like both and really dig how great it is people are making such good Capsules

Now the Bees capsules from Ben and Veronica are also really nice but felt a bit too dark for what I need for my next recordings.

Danny is in Canada is he ?

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on June 10, 2017, 04:14:30 PM
Quote
Danny is in Canada is he ?

Yup.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on June 10, 2017, 04:21:27 PM
Quote
Now the Bees capsules from Ben and Veronica are also really nice but felt a bit too dark for what I need for my next recordings.

From what I recall, the one in the Chunger sample is the BeesNeez M7, not the K7.
The latter gets great reviews. And it was Klaus' favourite after the Neumann FWIW.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Rixsta on June 10, 2017, 04:33:52 PM
Aha!! Ok thats interesting, do you know of any audio samples floating around that use that capsule ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KrIVIUM2323 on July 12, 2017, 07:42:15 AM
Hi,
I m going to start a 47fet build and would like to know what is the correct height of capsule in an original ( from headbasket plate to capsule center)?

Thanks.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: sebastianzet on July 14, 2017, 03:53:17 PM
Hi, i want to build this, i ordered the transformer and components and body, but then when i tried to order the pcb it said it is unavailable, what can i do? somebody please help. i'm worried i wasted money
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on July 14, 2017, 03:54:47 PM
Have you spoken with Dany (poctop)?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: sebastianzet on July 14, 2017, 04:06:16 PM
i emailed him, waiting on a response. i'm just a very nervous person and sometimes i do foolish things and i'm praying this wasn't a foolish thing. i'm antsy waiting for a response so i thought i'd try here. thanks for responding.
i guess the other option is if there is another pcb that would fit the gt-2b  body that creates a 47 fet. if anyone knows of one, please help me out. i am nervous i did something dumb.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on July 14, 2017, 05:13:39 PM
There's no reason whatsoever to panic. You'll be fine. What you need is a little calmness and patience. That's all.  :)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on July 14, 2017, 05:30:46 PM
i emailed him, waiting on a response. i'm just a very nervous person and sometimes i do foolish things and i'm praying this wasn't a foolish thing. i'm antsy waiting for a response so i thought i'd try here. thanks for responding.
i guess the other option is if there is another pcb that would fit the gt-2b  body that creates a 47 fet. if anyone knows of one, please help me out. i am nervous i did something dumb.

just wait until Dany have them back in stock.
There is no another PCB except Dany's.
You don't did something dumb or wrong. Just wait until it get back in stock.
If you are nervous, chill down. You have to learn to wait when you do DIY mics.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: micaddict on July 14, 2017, 06:23:12 PM
Oh, I forgot to mention faith.  :)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on July 14, 2017, 06:49:22 PM
All in stock now ,  ;D
Best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Lordward on August 30, 2017, 11:51:37 AM
Cool mic :)

I just made one with a K47 capsule and a FAB V8F transformer.   It's about 7db quieter than my 251, for example, but I'm highly impressed by the sound so far.  Great build :)

I used a T.Bone SCT 700 body.  Was a bit tight and I had to cut away a bit of metal but it works!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Lordward on August 30, 2017, 11:55:06 AM
Another shot
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Lordward on August 30, 2017, 11:56:51 AM
Last one..... 8)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Vac11 on August 31, 2017, 03:00:45 AM
Nice build, congrats!!!!

Can somebody confirm me a proper connection between FAB V8F transformer and Poctop´s u47fet pcb?

Black wire ......................................to BL pin on the pcb
Red wire .........................................to VI pin on th pcb
Blue wire ........................................to BR pin on the pcb
Yellow wire....................................to RT pin on the pcb
Brown wires ..................................to Chassis or GND pin on the pcb

Thanks

M.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Vac11 on September 11, 2017, 06:05:41 AM
Sound of this mic is beautiful!!!

I used Fab V8F transfomer and Maiku k47 capsule. Some vintage Tesla resistors. Transformer fits very well with plastic "L brackets"...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Vac11 on September 11, 2017, 06:07:30 AM
pic2
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Vac11 on September 11, 2017, 06:10:54 AM
pic 3
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: babaorum on September 27, 2017, 04:52:47 PM
Is the T-bone SCT700 the closest to the GT2B body for the U47 FET or is there a very close body to the original Neuman U47FET ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on September 27, 2017, 04:57:01 PM
Its the same body
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: FABMICROPHONES on September 27, 2017, 05:16:02 PM
Here's another mod  using a T-Bone SCT 700. The FAB V8 FET transformer fits using a couple of cable ties to secure.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: babaorum on September 28, 2017, 07:22:30 AM
Its the same body
ha ok cool  :D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Mrosso on October 04, 2017, 10:31:29 PM
Cheers, Enchilada!
Do you mind posting a pic of how you got the XLR insert to stay securely in the base of the Equinox body kit?
Much appreciated.

I know this is an old topic, but I just got an old Equinox U47 body that's missing the XLR connector (binder connector, I think is what it's called). Can you tell me how you solved getting an XLR connector in your mic body and which one you used?
Thanks
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Christopher L on October 29, 2017, 02:58:33 PM
I just finished my 2nd U47fet and I'm having trouble with the mic cuting on and off about every 30 seconds with a pop.  I did get some alcohol on the back of traces where polystyrenes are.? Anyone had a similar prob,  thanks in advance
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ilikeit on October 31, 2017, 10:03:32 AM
Hi all
I m starting me too!!!
PCB are ordered (poctop ;))
I want a GT2B body
and a thiersch capsule
Do you know What STS are ok?

Thanks a lot for this forum!!!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on October 31, 2017, 10:06:52 AM
I just finished my 2nd U47fet and I'm having trouble with the mic cuting on and off about every 30 seconds with a pop.  I did get some alcohol on the back of traces where polystyrenes are.? Anyone had a similar prob,  thanks in advance

you should verify your configuration at the 200 or 220M ohm pad , make sure you solder it in the no r+ pad if using the 220M resistor ,
Hope this helps,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ilikeit on November 06, 2017, 03:34:35 AM
Hi all
I m starting me too!!!
PCB are ordered (poctop ;))
I want a GT2B body
and a thiersch capsule
Do you know What STS are ok?

Thanks a lot for this forum!!!


Anyone??
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: wave on November 16, 2017, 01:33:55 PM

Anyone??

What do you mean by "STS"?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KrIVIUM2323 on November 16, 2017, 02:01:21 PM
I suppose Sts is the type of Thiersh's capsule mount as he offer different models.
If you want to stay thru to the original it should be the 58mm type (i say it should because it seems the capsule height is the same than 47 tube, but i never had a definitive answer about that.).
Anyway the capsule mount and headbasket of gt2 is different from an original so it should not matter too much.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: karloff70 on November 19, 2017, 11:44:08 AM
Hi chaps......has anyone built this thing with the Sowter 1303 at all? Any impressions or sound files?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on November 19, 2017, 11:48:04 AM
I had do it.
It just sounds good.
I used it with a Thiersch M7.
Used it on my Bassdrum.
Just tell me, what kind of soundfiles you need.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: karloff70 on November 19, 2017, 03:59:16 PM
Wow, thanks! Any tiny snippets of acoustic guitar or vocal would be very interesting. Which Thiersch do you have?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on November 19, 2017, 05:11:35 PM
Well acoustic guitar could be difficult.
But I’ve a vocal snipped.
Just pm me your email and I’ll send you everything.

I use a Thiersch M7 redline Capsule.
But I’ll change them when my Maiku k47 Capsule arrive, cause I want to use the thiersch in my M49.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ilikeit on November 20, 2017, 04:35:29 AM
I had do it.
It just sounds good.
I used it with a Thiersch M7.
Used it on my Bassdrum.
Just tell me, what kind of soundfiles you need.

Hi TillM
What is the body of your microphone?
If it is a GT2B what is the height of your thiersch capsule holder?
Thanks!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on November 20, 2017, 06:47:25 AM
Yes I take the Tbone sct700 body, which is the same.
The mount is the smallest you get from Thiersch.
Should be 52mm high.
Don’t forget to take a small acrylic plate under the holder.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ilikeit on November 20, 2017, 08:59:41 AM
Yes I take the Tbone sct700 body, which is the same.
The mount is the smallest you get from Thiersch.
Should be 52mm high.
Don’t forget to take a small acrylic plate under the holder.

Thank you for your answer!
where did you buy the acrilic plate?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on November 20, 2017, 12:14:19 PM
I do it on my own ;)
https://www.wir-bedrucken-shirts.com/acrylglas-rund-2-mm-staerke-durchmesser-von-10-120-mm.html?MODsid=28081445bc6803a2a87aa88dc0fd3824

I take 12mm and drill a 3mm hole in the middle.
Its just because the M7 don't like metal plates.

Here is a sound sample.
Thiersch M7 Redline, Sowter 1303.
It's use it just on my kick. No processing. Recorded through my Hairball Lola with gar2520 DOAs
https://www.dropbox.com/s/6gm9a4t7z0u15w0/Kick%20Out%20U47FET%20with%20Thiersch%20M7%3ASowter.wav?dl=0
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ilikeit on November 20, 2017, 03:43:03 PM
I do it on my own ;)
https://www.wir-bedrucken-shirts.com/acrylglas-rund-2-mm-staerke-durchmesser-von-10-120-mm.html?MODsid=28081445bc6803a2a87aa88dc0fd3824

I take 12mm and drill a 3mm hole in the middle.
Its just because the M7 don't like metal plates.

Here is a sound sample.
Thiersch M7 Redline, Sowter 1303.
It's use it just on my kick. No processing. Recorded through my Hairball Lola with gar2520 DOAs
https://www.dropbox.com/s/6gm9a4t7z0u15w0/Kick%20Out%20U47FET%20with%20Thiersch%20M7%3ASowter.wav?dl=0

Yessss it s a great sample !
Thanks for your tips with the acrylic I didn't know!
I live in France any body have a shop for me ?
I don t speak Germain so it s very difficult to make an order om this website!
Ans for a piece about 1€ i paid 12€ for the travelling ...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KrIVIUM2323 on November 20, 2017, 04:14:47 PM

www.plastiquesurmesure.com
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ilikeit on November 20, 2017, 04:30:05 PM
www.plastiquesurmesure.com
I m must stupid....
Thanks for the link but everything looks like  very expensive !
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KrIVIUM2323 on November 20, 2017, 04:50:04 PM
Prices given are for 1m2.
Ask for a piece cut to your needs (10cm/10cm min).

Les prixs sont donnes pour 1m carre... Fait faire une decoupe de 10cm carres (ou aux dimensions minimum) que tu redecoupes aux dimensions requises... c est plus abordable comme ca. Ceci dit tu as une limite n dessous de laquelle tu devras payer un forfait de decoupe.
Sinon tu vas dans une grande surface specialise en bricolage et tu demandes une decoupe de plexi, acrylique ou pmma...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: karloff70 on November 23, 2017, 06:28:40 AM
Well acoustic guitar could be difficult.
But I’ve a vocal snipped.
Just pm me your email and I’ll send you everything.

I use a Thiersch M7 redline Capsule.
But I’ll change them when my Maiku k47 Capsule arrive, cause I want to use the thiersch in my M49.
Oh wow, then I'll wait if I could, as I am thinking of building it with the Maiku and the Sowter, so would be amazing to hear anything at all from that combo to give me an idea whether it will do what I think it will.... 8)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on November 23, 2017, 09:08:38 AM
I will send you a sample, when I change the Capsule.
Just have to wait until Banzai shipped the M49 bodies, he just have to wait for the Binder connectors.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: karloff70 on November 23, 2017, 11:54:59 AM
I will send you a sample, when I change the Capsule.
Just have to wait until Banzai shipped the M49 bodies, he just have to wait for the Binder connectors.

Amazing, thank you!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on December 04, 2017, 07:54:27 AM
Hello there.
I'm having trouble with the board. Looks like something's wrong

That's the regular input feeded where the capsule lands.
(https://i.imgur.com/LBjzwla.jpg)

Here's the output.
(https://i.imgur.com/yRkcosA.jpg)

And this is what I got on B/BB
(https://i.imgur.com/La4t8gs.jpg)

I did re-heat everything and re-solder some suspicious pads. I also checked C1, C2, C3, R2 (although I just can guess it's more than 20M) and replaced T2. Voltages seem fine, considering that I only got 44v from the phantom.
 I'm quite lost actually.  :-\
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: poctop on December 05, 2017, 08:13:30 AM
Did you follow the proper instruction for the 200 or 220m resistor in No R+ pad ?
this is a common mistake ,
hope this helps,
best,
Dan,
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on December 05, 2017, 09:40:22 AM
Thank for replying.

Well I think I did. :(

(https://i.imgur.com/BKa2Im1.jpg)

As I can't directly test the 200M, I did run a parrallel test for the 2 (200+20) of them. I got a perfect 18.18M, so both are ok.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: niconeemis on January 02, 2018, 11:54:36 AM
I'v just finished to build the board.
i have some trouble with it.

I have a reallly reallly  tinny  output level. but it seemed to be a clean signal (my voice for test). But with or without the 48V i have the same little output signal.

i'v checked everythin Twice. The cinemag is wired as the pictures. The 220M resistor is at the right place. the  jumper instead of the pot and the 6.8r at r6 too. where can i start to trouble shoot?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: niconeemis on January 02, 2018, 11:56:24 AM
and for putting the tranny in place i printed this thing : (https://www.dropbox.com/s/3dzygeizf10lp91/IMG_1053.JPG?dl=0)
https://www.dropbox.com/s/3dzygeizf10lp91/IMG_1053.JPG?dl=0

and here is the STL file if you want to print it too :

https://www.dropbox.com/s/clsqunge1x123hf/circuit%20adaptation%20U47FET%20V4.stl?dl=0
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Dcarrow555 on January 12, 2018, 05:22:49 PM
Hello,

I am working on the D-47Fet. I am having some trouble figuring out where the back diaphragm is placed, I might just be missing it but i can't seem to find it on the schematic. I am also confused about the FD. the schematic seems to say something other then the build thread.

I would be very appreciative of any feedback.

Cheers
D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: KrIVIUM2323 on January 12, 2018, 05:31:51 PM
Hi,
There is no back diaphragm used in a u47fet, this is a cardioid (supercardioid in fact) mic only, D47 fet is the same.
If you use a dual diaphragm capsule just leave the back diaphragm unconnected (you can use a sleeve of heatshrink to cover the end of cable).
For the front diaphragm just follow the build guide, it is right and follow the original schematic.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Dcarrow555 on January 13, 2018, 09:40:05 AM
Thank you so much for your reply! That makes sense why i couldn't find the BK.

Cheers
-Dylan
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on January 13, 2018, 09:42:59 AM
Hi there,
As I wasn’t able to find out what went wrong, I started to build a new one.
I did check everything twice, ´ve been very carefull : same sh*t.
Now, I am an unhappy owner of two non-working pieces of crap.
What a waste of time.  :'(

Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on January 13, 2018, 11:08:01 AM
You missed r16 the 10M resistor.
And please check your floating connection with the 1g resistor and so on. This seams not right to me.
Where are you living ?
Also take some isopropanol and clean.
Be careful with the styroflex.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: deveng on January 13, 2018, 11:17:08 AM
Boomfred,

Correct me if I'm wrong but from the pictures of your bench, it looks like you're injecting a large signal.   If you're using a simple capacitor to simulate the capsule, the signal is very small, in the order of milivolts.   You're output may just be clipping.  What is the level you're injecting and what is the voltage you read?

Regards,
Jeff
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on January 13, 2018, 11:21:48 AM
Thanks for trying with me.
I did not miss r16, I had to rewire it from the other side because I tried too much/too hard to find out what went wrong. Project n2 got everything in place.
The  floating connection have been checked and re-checked on both projects.
And I did clean almost everytime.
But obviously, I do something wrong.
I’m in France.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on January 13, 2018, 11:47:07 AM
Did you use everything from the BOM?
I Used first  the bc212 at my build, as on the original schematic,
They don’t work. So I take the 550/560 from the BOM.
What happen, when you install a capsule.
Did you check the voltages as shown on the schematic ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on January 13, 2018, 12:02:11 PM
it looks like you're injecting a large signal.   
:o  :-[
Thank a lot Jeff. I was hitting that poor thing as hard as I can. Shame on me.
Of course,  it now looks like it is working.  :-[   ::)  ;D
I do have work / tests to do to find out if everything is fine but it seems way better.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: deveng on January 13, 2018, 01:01:21 PM
boomfred,

Next thing to do is use some isopropyl alcohol and clean the solder flux off the pcb.   Make sure its very clean as any flux on a high impedance circuit can mess with your signal!

Regards,
Jeff
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on January 15, 2018, 04:57:42 AM
So, tests have been run, and everything works perfectly.

My advice : don't try to build this mic while you are trying to repair an Acoustic 126. Levels don't match.  ;)
Did I mention how dumb I am ?

Did you use everything from the BOM?
I Used first  the bc212 at my build, as on the original schematic,
They don’t work. So I take the 550/560 from the BOM.
What happen, when you install a capsule.
Did you check the voltages as shown on the schematic ?
I did stick to the BOM, and of course voltages were perfectly fine.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: babaorum on January 15, 2018, 01:44:16 PM
(https://groupdiy.com/index.php?action=dlattach;topic=49758.0;attach=46972)

how did you make the edges around the transformer? pieces of wood ? and is it black tape?

Thanks,
Baba
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: babaorum on February 18, 2018, 01:07:16 PM
To use the additional pad :
Do I have to put the 220M R but not in the R+No Hole or use 200 + 20 R ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: alx on February 23, 2018, 10:01:04 AM
Hello there !

Quote
To use the additional pad :
Do I have to put the 220M R but not in the R+No Hole or use 200 + 20 R ?

babaorum : from what i've understood,  if you have a 220M resistor, just put it like the picture above, with an end into the No R+ hole.
if you don't , and if you have a 200M + 20M resistors then just put them in R2 and R2+ (and nothing in the No R+ hole).


I just finished mine, it has a clean sound (no hum) , output level is ok,  but it has no bass at all. It starts to cut below 300/400Hz.
the attached image is a pink noise sent to my monitors (to the right) , and recorded with the U47 FET (to the left) ...
could it be the styroflex ?

(edit : can't upload the image, error message saying the upload folder is full)

Thanks in advance...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: babaorum on March 03, 2018, 09:37:26 AM
Ok Thanks, sorry the pad (attenuation) has no link with the R 220  ;D

I'm on the last stage of the project, Ihave a little question about the GND hole on the pcb , when we have the T49 transformer we don't need to have this one isn't it ? So we connect the XLR only to the 1-2-3 and leave the GND empty Am I right ?

Baba
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: alx on March 07, 2018, 12:04:14 PM
Hello again,
i still have a problem on mine : clean sound but no bass at all.
i checked my solders , component orientation... nothing strange.
i tested with a spare RK12 type capsule, same thing.
so it's not my RK47, the problem comes from the circuit.

i compared the U47 fet with another DIY mic i built (with RK47 capsule),  ECM8000, and AT4033.
if you look at the result, you'll see why i think there's a big problem on my built :
(https://i.imgur.com/ZFpoxiK.jpg)

does anyone have a clue ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ln76d on March 07, 2018, 12:12:22 PM
Hello again,
i still have a problem on mine : clean sound but no bass at all.
i checked my solders , component orientation... nothing strange.
i tested with a spare RK12 type capsule, same thing.
so it's not my RK47, the problem comes from the circuit.

i compared the U47 fet with another DIY mic i built (with RK47 capsule),  ECM8000, and AT4033.
if you look at the result, you'll see why i think there's a big problem on my built :
(https://i.imgur.com/ZFpoxiK.jpg)

does anyone have a clue ?

Did you used all original parts values? Is your build with switchable HPF? If not - check did you didn't do a fixed HPF by mistake.
Another thing which comes to mind - transformer wiring??
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: alx on March 07, 2018, 12:27:48 PM
Thanks a lot for your reply ln76d !
yes i used original values. (i used the mouser BOM of this topic) 
my built is like the one on this topic, so it has a jumper for the Low Cut,
but i didn't put the jumper.
but I thought about that too, so i tested that the LC was not engaged without the jumper.
(anyway it starts to cut LF  around 300/400 Hz, so that would be a huge Low Cut.)

for the transformer (AMI T49),  i'm going to check that again...
(if i recall , when i read the topic, there was 2 different answers about how to wire it, so maybe i picked the wrong one ! :-) )

thanks again !
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: alx on March 07, 2018, 01:22:01 PM
stupid question :
on the T49, you need to connect the inside pins of A-B and of C-D like that ?
(https://i.imgur.com/YTQN8Ga.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: alx on March 07, 2018, 01:47:01 PM
so my T49 seems to be correctly wired :
1 (rt) : A
2 (br) : B
3 (vi) : D (xlr pin 3)
4 (bl) : C (xlr pin2)

i asked the stupid  question above because on the pcb, the 1(rt) and 2(br) are connected together (continuity test) when the inside pins of the transformer are connected. it doesn't seem normal to me (but maybe i'm wrong)
1(rt) and 2(br) on the pcb are not connected together when i disconnect the inside pins of the T49, but in that case, no sound (or very weak ) is coming out the microphone except "wind"...

so, are the 1(rt) and 2(br) are supposed to be connected together ?
if not, the T49 has a problem, right ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ln76d on March 07, 2018, 05:59:17 PM
For the colors,  i didn't check the schematic or anything it's related to.
Isn't t49 exactly symetric - is there no possibility to connect it opposite? Or are there markings a/b/c/d?
I rather doubt that there's something wrong with transformer, untill you didn't overheat connector pins and loosed internaal connection.
If you are not sure transformer proper orientation then measure resistance A/B should be higher than C/D.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: alx on March 08, 2018, 02:21:24 AM
thanks again ln76d,
yes the a/b/c/d are written directly on the T49.
(http://www.tab-funkenwerk.com/sitebuildercontent/sitebuilderpictures/T49SpecSheet.jpg)

i checked the resistance :
 A/B = 15 ohm (so i guess my multimeter thinks it's like continuity)
 C/D=675 ohm
it's the opposite of the values i read in this topic !  :o
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: alx on March 08, 2018, 02:35:50 AM
ok, so i "reversed" the connections on the T49 (A/B =xlr 2/3, and C/D=pcb 1/2) and...
plenty of bass ! beautiful sound !

so the folks at AMI put a sticker on the T49 to mark the A/B C/D, but they put it the wrong way ! (on mine)  >:(
i would have preferred no sticker at all...
but i'm dumb, i measured the resistance of A/B C/D but did not noticed they were reversed ...

anyway, i'm happy now..
thanks a lot  ln76d for pointing the right direction !
(and thanks to poctop for this great mic, now i want another one !)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jeid on March 23, 2018, 09:32:10 AM
Hello, I got my PCB's the other day, they are lovely looking. I've ordered pretty much everything but I'm not sure what XLR type to get to fit my SCT700/GT-2B unit? Any help on that front?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on March 23, 2018, 09:41:59 AM
Hello there,
I picked that : https://www.mouser.fr/ProductDetail/502-QG3M
The one on the right.
(https://www.mouser.fr/images/switchcraft/images/502-QG3FD.jpg)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jeid on March 23, 2018, 10:08:47 AM
Hello there,
I picked that : https://www.mouser.fr/ProductDetail/502-QG3M
The one on the right.
(https://www.mouser.fr/images/switchcraft/images/502-QG3FD.jpg)

Thanks mate, typically, I'd just placed my order for the BOM, but I've managed to get Mouser to add this on. Appreciate the help :)
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Hank Dussen on March 26, 2018, 03:55:50 AM
Finished this one a few weeks ago.
Maiku K47 capsule and FAB V8f transformer.
The hardest part was fitting the transformer properly.
Also, I lowered the baseplate on which the capsule-holder sits to lower the capsule with 2 nuts. (see picture)
I know it's supposed to sit high in the basket but before lowering it, the capsule was 1mm from the top of the basket. That's too close for me.
So far I’ve used it on vocals and kick drum and it sounded excellent on both.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jeid on April 10, 2018, 07:24:00 PM
ok, so i "reversed" the connections on the T49 (A/B =xlr 2/3, and C/D=pcb 1/2) and...
plenty of bass ! beautiful sound !

so the folks at AMI put a sticker on the T49 to mark the A/B C/D, but they put it the wrong way ! (on mine)  >:(
i would have preferred no sticker at all...
but i'm dumb, i measured the resistance of A/B C/D but did not noticed they were reversed ...

anyway, i'm happy now..
thanks a lot  ln76d for pointing the right direction !
(and thanks to poctop for this great mic, now i want another one !)

Just had the exact same issue with mine, thanks for this, saved me a whole lot of bother.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on June 10, 2018, 02:30:58 PM
Greetings machines!
Comment that I acquired some PCB boards and I see that mine are a little different from the ones I see in the thread of the micro, in the picture that I attached I also have to make the connections in that way all to leg G, or I have to do it correctly since in mine yes that there are holes for the components?

Thank you very much!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on June 10, 2018, 02:50:23 PM
Yes they are different cause you ordered your set from micandmod.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on June 10, 2018, 03:01:40 PM
So you know if you have to mount it well in the holes? Or do we have to do the same with C3, the resistances and that?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on June 10, 2018, 05:49:40 PM
Sorry I can’t help you.
The pcb design looks similar.
Seams like the turret is for the floating connection.
It’s better you ask micandmod.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Hank Dussen on June 13, 2018, 08:50:32 AM
This week I did some recordings for a band I play in and all of us were really impressed how good my D-U47fet (see a couple of posts back) sounded on anything we've put it in front of (soft female vocal, screaming male vocals, double bass, percussion, vibraphone, room,…)
just to let you know…  ;D
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: shot on September 29, 2018, 08:53:21 PM
I'm totally stuck with my mic!

After few days of troubleshooting I'm out of ideas what to do.
Voltage on B pad is oscillating from 2v to 44v. At first when mic is turned on it stays at 0v for about 15 seconds and then it starts going wild. I get sort of motorboating sound out of the mic.
Other voltages are also suspicious - for instance T4 has Vc-38v, Vb-10v, Ve-13v.
Voltage that is supposed to supply the capsule measured at pad A is 13.8v. Should that be higher?

I've checked if there is some wrong value/component present, after that I replaced T5, T6, T4... than I checked all board-to-board wiring, tried injecting sine signal at R1/C1 junction (used ceramic 68pf instead of real capsule)...

What else can I do?

What could be the cause of this oscillation at B pad?

:(

Luka
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: moamps on October 01, 2018, 03:55:39 AM
Have you checked tantalum capacitors orientation and transformer connection?
What's going on with the voltage on emitter of T7 during  motorboating?
Voltage on Pad A is high-ohmic source so you can't measure it correctly with a standard DVM.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: shot on October 01, 2018, 11:51:44 AM
Tantalums are correctly oriented... unless there's a print error on them!
Transformer is also correctly oriented. But I found on this thread that even when transformer is upside down it would still produce sound, even though that would be low volume and lacking bass... So I guess this is not a problem.

Voltages on T7 are Vc=44.1, Vb=42.5, Ve=42.5
Emmiter and base voltage drift a bit when mic is oscillating, like +/- 0.3v

I'll do a test to replace C6, C8 or C10 tantalums with electrolytic caps. One by one. Maybe there's something with one of those...

:)

Luka
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: shot on October 01, 2018, 05:01:28 PM
I did it! Fixed it!

How? Well I don't know?
I've swapped T2 and FET, and also I swapped all the wires that connect two boards.
I'm sure that the problem was not in those wires since I tested their continuity few times, but since I desoldered them few times they were all burned up and looked ugly.
This was the third FET I've put into it and could be that previous two were somehow faulty.
Or it was transistor T2... don't know...

Mic sounds very nice! I'd say fantastic, but wait 'till I try it in the studio. For now I only tried it on the bench speaking blablabla into it. Very detailed mids and bottom end!

What I noticed is that it's output is significantly lower than two previous mics I've built (G7 and Ela m 251). But that's fine.
I'm using GZT-87 transformer (9.5:1) and K47 capsule from Banzai's group buy couple years ago. It's in the donor body bought from Chunger's shop (GT-2B)

Also, I've noticed that capsule mount provided with donor body is too high! When the capsule is fitted, metal bar that connects the grille was right at the center of the capsule. And capsule was too high, only few millimeters from the top grille. When I changed to low profile mount I think sound changed a bit. For the better of course!
So just as a tip for other builders, if you use this body be sure to check where your capsule is when assembled. Maybe order a low profile mount along with donor body at the beginning since it's cheap and could come in handy.

In the end... thank you Dan, thank you Moamps and entire community!

:)

Luka
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on October 16, 2018, 06:07:23 PM
Regards! a silly question .... the black cable of the cinemag transformer cm-13101, what is it for? I am a beginner and it is my first micro, thank you!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on October 17, 2018, 03:44:50 AM
It’s ground.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on October 18, 2018, 02:55:48 PM
ok! and i connect to the gnd of the pcb o other site?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: boomfred on October 18, 2018, 03:10:10 PM
Indeed
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on October 21, 2018, 06:08:37 PM
Regards ! I finished the microphone and it does not work, the connections of the cinemag transformer are fine so on the pcb? and the capsule? Thank you!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on October 21, 2018, 06:09:58 PM
connection capsule
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on October 21, 2018, 06:10:52 PM
general capsule
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: ViciusbeatZ on November 06, 2018, 03:51:52 PM
any help!! please!!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on November 07, 2018, 03:42:21 PM
this is not the PCB from Dan.
The connection from the Cinemag you find in this thread, just search for it.
It's hard to tell, when you not tell us what don't work ?
Check all your soldering, transistor positions and resistor values first.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jrmintz on December 24, 2018, 07:39:37 PM
A question - the turret marked G that looks like a star ground has the insulator to keep it from contacting the board and five components attached to the top side. What attaches to the bottom side? Anything?

Thanks
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jrmintz on December 29, 2018, 09:46:21 AM
...the isolation pin on the 47FET Just supports the HZ component that connet to the FET ,

Best,
Dan,

Ah, the answer to my question, on page 18, of this thread. Pardon my laziness...
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jrmintz on December 30, 2018, 12:31:03 PM
http://www.sethglassman.com/FET47%20test.mp3 (http://www.sethglassman.com/FET47%20test.mp3)

Unfortunately, my U47 FET is making a weird rhythmic noise and not passing audio. An mp3 of the noise is linked above. Can anyone suggest a place to start looking for the problem? Fet installed incorrectly? Thanks.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jrmintz on December 30, 2018, 06:03:31 PM
My voltages are definitely weird:

At the intersection of R20 and R21 I have 11V.
At point ‘B’ on the board I have 9V.
At the intersection of C7 and T5 I have 11V,
13.2V at T7 and R17,
11.4V at T5 andR16.

I’m using an outboard AKG phantom supply that’s putting out 53V, and at the pads that connect to the XLR I have 13V between pin 2 and ground and pin 3 and ground. Obviously something is pulling the voltage down.

Edit, a couple of hours later: The problem is I seem to have bought some counterfeit 2N3819s. I tested the others in the batch I bought and they read like BJTs, not JFETs, thought they're marked 2N3819.  Caveat emptor.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jrmintz on January 02, 2019, 01:29:18 PM
I wound up using a J201 FET in the mic and I just recorded some bass drum - it sounds amazing! I used an AMI FET47 transformer and a BeezNeez capsule. I'm really thrilled - thank you Poctop!
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: hervemusic on February 04, 2019, 08:25:09 AM
I have the same problem on my DIY U47FET
i have just a little sound
i have not gain

all the capacitors are goods and the resistors ans fet

My transformer is a cinemag 13101

Where is the problem
help me please 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: TillM on February 04, 2019, 06:58:00 PM
I have the same problem on my DIY U47FET
i have just a little sound
i have not gain

all the capacitors are goods and the resistors ans fet

My transformer is a cinemag 13101

Where is the problem
help me please

First check again all transistor directions and if you choose the right ones.
Then check your soldering at the Hi-Z area.
Where did you source your FET ?
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: jrmintz on February 07, 2019, 02:51:35 PM
Check to be sure your fets really are fets.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: rockinrob86 on February 07, 2019, 03:41:51 PM
Will these pcbs fit in these bodies?  https://store.studio939.com/product/budget-47-body-kit
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Ricardus on February 07, 2019, 05:40:53 PM
Check to be sure your fets really are fets.

Yes. Lots of fake 2N3819s on Ebay. I know. I bought some.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: useme2305 on February 08, 2019, 06:57:25 AM
Will these pcbs fit in these bodies?  https://store.studio939.com/product/budget-47-body-kit

yes, this body wont be too small that's for sure. the boards wont go in there without any extra holes in those rails along with some metal angles.
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: maarvold on March 10, 2019, 12:40:01 PM
Around 36 hours ago I finished my D-U47 FET build: Alctron GT-2B body, Ben & Veronica Sneesby's K7 capsule and Dr. Mark Fouxman's (Samar) transformer.  I built it specifically for kick drum and can't wait to try it.  It fired up and worked right away (THANKS!!) and, I have to say--the sound on my recorded speaking voice makes it seem like it might also be a great vocal mic: clean, fast,  'chesty' and powerful-sounding, low sibilance (a BIG plus) and it has 'vibe'.  Excited to get some hours of real recording on it.  THANKS to all who made this journey possible!!!  And I'll report back on the sonics. 
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: Govinda Doyle on March 29, 2019, 08:32:07 AM
hey guys
I just built one of these, but im having a strange noise
no sound coming from capsule but im having this rhythmical noise?
do I have the capsule connected wrong?
thanks in advance
G

https://www.dropbox.com/s/2wwcq5mohq5u96c/rhythmical%20noise.mp3?dl=0
Title: Re: Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread
Post by: maarvold on May 04, 2019, 01:58:32 PM
The 47FET I built specifically for kick drum (and love for that) has been getting some use in other areas: I used it on Dun Dun (a BIG drum with animal hide heads that still have the fur on them) and also on trombone, where it gave me an 'instant James Pankow' (of Chicago) sound.  Very happy with this mic.