Neumann U47FET Clone: D-U47 FET Microphone Project PCB Build thread

[adeptusmajor]

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

 

[Spencerleehorton]

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.

 

[Spencerleehorton]

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.

 

[wave]

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

 

[poctop]

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]
Enjoy !

Best,
Dan,

 

[Spencerleehorton]

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.

 

[useme2305]

does anyone know if the MXL R144/R44 ribbon mic body is suitable for the D-U47FET project?

 

[poctop]

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

 

[useme2305]

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

 

[poctop]

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

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,

 

[useme2305]

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?

 

[poctop]

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

 

[wave]

That is a very nice transformer!

Dave

 

[Melodeath00]

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?

 

[poctop]

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?

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

 

[Melodeath00]

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!

 

[useme2305]

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.

 

[Winetree]

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?

 

[poctop]

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.

Best,

 

[Spencerleehorton]

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.