Neumann Vintage U87 Clone : Build Thread.

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poctop

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D-U87 Build Thread

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

Mouser Cart including all options ( 60M and 68M included also 2 different PN  for 2K2 resistance)
important note :The BOM already contained alternate part number for the 2.2K (delete whatever is not available at the moment and also there is both the 60M and the 68M listed in there for you to decide both will work fine
just delete from your order the one you wont take,  the 68M is less expensive !


Most Recent BOM here :
http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=1AD602D54E

Sound Sample Provided By Chunger and Exhaustive Build thread  here http://www.groupdiy.com/index.php?topic=49389.60

Demonstrative Video Provided By Peterson Goodwyn at DIY Recording Equipment and Matthew Jenkins.  :)
http://youtu.be/DtNH46jpwJo


Build Demonstration
http://www.vintagemicrophonepcbkit.com/Neumann%20U87%20Build.htm

Large PCB version in SYT-5 mic body
58d1402a01fad.jpg


58d1402a01fd3.jpg


Taper Version in BM-600 Type mic Body
58d1402a01fe5.jpg


58d1402a01ff6.jpg


58d1402a02008.jpg




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

The Original Version Contains Polystyrene Filter Cap,  as this is an option not included in the BOM it may be ordered  via the webstore

Styro Kit includes
1 X 10pf Styroflex/630V
1 X 220pf Styroflex/630V
2 X 470pf Styroflex/630V ,
1 X 560pf Styroflex/630V ,

Read This First : Assembly Instruction , Excel BOM and Tips For Assembly and  Important Considerations Here: https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02019.xlsx




this will fit the Aurycle Micropone the MXL or any tapper standard Fet Mic Body
This is a Combo Set (2 Boards)
BOM , Layout ,Schem, ..... For this project,

Tutorial Document Thanks to UDO on how to wire the behringer B2 Pro switch board Here:

https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a0202b.pdf


How to make it in a behringer B2 thank to jasonallenh

https://www.dropbox.com/s/zm4eexpvpmhwab2/USING%20THE%20AMERICAN%20B2%20FOR%20DANYs%20U87.pdf?dl=0

B1 Reference Voltage and Schematic https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02050.pdf

B2 Reference Voltage and Schematic https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02062.pdf


Here a Fantastic FET Behavior Calculator ( Thanks To Matador)
http://www.musicalsparks.com/images/curve_tracer/jfet_bias.php

Important note :calibration resistor R11 is not Included in  the Bom as it is specific for each  FET.
use the potentiomter in the BOM to determine R11 Value.
Consider having those on hand the value of R11 Will be approximatively
Ranging from 7k to 12k


The new version of the Board include the Pot or resistor Package much easier
 
Mouser Cart including all options ( 60M and 68M included also 2 different PN  for 2K2 resistance)
important note :The BOM already contained alternate part number for the 2.2K (delete whatever is not available at the moment and also there is both the 60M and the 68M listed in there for you to decide both will work fine
just delete from your order the one you wont take,  the 68M is less expensive !


Most Recent BOM here :
http://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=1AD602D54E

58d1402a02074


Dimension Here : https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02085.doc

Needed For this Project is a K87 Type Capsule With isolated backplate.

Best suited Capsule for this Project for this project: K87i by Peluso and can be found here :
http://www.pelusomicrophonelab.com/parts/Capsules.html
58d1402a02096

Best suited Capsule for this Project  The RK-87 by Microphone Parts and can be found here :
http://microphone-parts.com/rk87-microphone-capsule/
http://microphone-parts.com/faq/
58d1402a020a7


Best suited Capsule for this Project for this project: K87 by TSKGUY and can be found here :
http://www.groupdiy.com/index.php?topic=49859.0
58d1402a020b6


capsule connection the  Proper Way to make sure front is front and back is back:
  Side A
58d1402a020ca.jpg

  Side B
58d1402a020dc.jpg

58d1402a020ed.gif



See by your self Here Thanks To John Peluso :):  Frequency Response Test from John Peluso (K87-PK87i) : https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a020fd
http://www.pelusomicrophonelab.com/parts/Capsules.html

Here are the best suited transformers for this project :

New T13 From Tab-Funkenwerk The T13 was designed specially for the u87 circuit by Tab-FunkenWerk

http://www.tab-funkenwerk.com/id133.html


CM2480 from Cinemag http://cinemag.biz/mic_output/mic_output.html
58d1402a0211d.jpg


New Peluso T87 Specialy designed for this application
58d1402a02130.gif


More Info here  : http://www.groupdiy.com/index.php?topic=47350.300

How To measure FET Idss By Matador https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02141.jpg

FET Biasing Method By ZapNSpark : https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02152.pdf

Reference Version 16 Schematic: https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02163.jpg

Manual and Version 21 Schemo : https://cdn.groupbuilder.com/groupdiy/u/39511/58d1402a02175.pdf

Tuning Hint : http://www.groupdiy.com/index.php?topic=47350.340

To Bias Fet, make sure you install R6 backward in reference to the silk screen like this:
this is Valid for Large Version and Taper Version do not do this for the Blue PCB version
58d1402a02187.jpg

58d1402a0219a.jpg


Tuning Thread : http://repforums.prosoundweb.com/index.php/topic,11630.0.html

Precious Info on how to use a scope to Bias a Fet (Thanks To Matador) http://www.groupdiy.com/index.php?topic=46109.40

Here is a software based oscilloscope for those interested :
https://cdn.groupbuilder.com/groupdiy/u/39511/58d0281993732.exe

Here a List of suggested Mic Bodies ( Thanks To ChuckD )

All Switches
Behringer B-2 Pro 
MXL 2010               
Filter and Pad Only
Aurycle A460
MCA SP1 
CAD GXL2400
Carvin CM87S
No switches:
Gauge ECM 87
Nady SCM 900


Cheers Dan,
 
Is it possible to amend this thread with that thread? There is a wealth of information over there in among the 'I'll take two' (including my own ....) posts!
 
I was wondering, since my 2480 is already engaged to another design, if there are any other transformers that could be recommended for an authentic U87 sound (Peluso makes some Neumann copies, but which one?).
Poctop, which transformer would you choose out of the two you've used? BTW, what is a 090415 transformer (manufacturer, price, website, etc.)? Better yet which mic would you suspect works better for vocals out of the two you have built?
I knew I wanted a U-87 for vox, but I know I can't turn down a better sound, IF it's just as versatile and performs just as well over a wide variety of applications.
I guess what I'm asking is, does the "API" U87 still sound like a U87? Is the change subtle or drastic? Is it like running a U87 through a different preamp, or are they totally different beasts?

One last thing. Are there any cap preferences on this circuit yet? I'm still on the fence about this part. I'd normally use Illinois caps, but I know tants are the standard for that circuit (despite their eventual drift). I'm sure the BOM caps are sufficient, but not sure which type will give me an authentic sound and long-term reliabilty (hence my concern for the tants). Thanks for your time.
Sorry so many questions, but someone's gotta ask...

-James-
 
HellfireStudios said:
I knew I wanted a U-87 for vox, but I know I can't turn down a better sound, IF it's just as versatile and performs just as well over a wide variety of applications.
I guess what I'm asking is, does the "API" U87 still sound like a U87? Is the change subtle or drastic? Is it like running a U87 through a different preamp, or are they totally different beasts?

One last thing. Are there any cap preferences on this circuit yet? I'm still on the fence about this part. I'd normally use Illinois caps, but I know tants are the standard for that circuit (despite their eventual drift). I'm sure the BOM caps are sufficient, but not sure which type will give me an authentic sound and long-term reliabilty (hence my concern for the tants). Thanks for your time.
Sorry so many questions, but someone's gotta ask...

-James-

So Far, I have done a Total replica of one as this date with the original capsule K87 and the original transformer 090415
and then the results is incredible the only difference i can make is the tiny lost of high's due to the worn out capsule ,  i have used the tantalum all the way and the polystyrene as the original,  if you put tant in there dont worry about the life of these there is a lot of old u87 working out there. ;) if you look in the BOM there only the 10pf  polystyrne that is not on the BOM but all other option are mentionned,
the other one was based on the peluso and 2480 it a bit  less dirty than the original because of the very dirty 09415 but with more punch to it , however the 09415 is not readiliy available and might be pricy unless you want to try reaching neumann with this :-X, nothing is imposible ;D  i wish i had some suggestions here for alternative with the trannie i just went on the 2480 because there good and cheap.

If anyone would like to suggest some specific trannies i'd love to have them in your mics too, 
I think Marik makes one that suits the u87 ?,
peluso ? thinks he does the bv8 only.
Ioaudio ?  good candidate  ;D

So at this point i can't wait to hear some opinion out there.
that will problably explains it better :)
as for wich one is best then your ear shall decide.

Hope this Helps,

 
Okay:

I ordered Peluso K87i capsules for my mics. However there are only three wires coming off them - the centers of the capsules and one tag on the front for the capsule body. What about the rear body? Did peluso just forget to put a tag on the back? Is it safe to just solder a wire to one of the tension screws? That seems like madness to me, but then again that's what the tag on the front is connected to so it should prob be fine.

Thoughts?

Thanks
 
Marcocet said:
Okay:

I ordered Peluso K87i capsules for my mics. However there are only three wires coming off them - the centers of the capsules and one tag on the front for the capsule body. What about the rear body? Did peluso just forget to put a tag on the back? Is it safe to just solder a wire to one of the tension screws? That seems like madness to me, but then again that's what the tag on the front is connected to so it should prob be fine.

Thoughts?

Thanks

I dont remember exactely how i dod get mine or ended solder-screw a screw on the backplate ,

just to make things right drop him an email at

[email protected]

and let us know please ,

hope this helps,

 
I sent also an email to make sure with the capsule..

I will keep you posted ,
D,
 
The Answer is the front backplate tab already on the capsule is for the front capsule so this is how you recognize the front ,
the (back) backplate will connect via a tab that you need to supply ( Peluso Wisher will be providede one) and attached to the mounting saddle connection so it will make contact will the back backplate,
Hope this helps,
Dan,
 
To Mention here

Regarding the Peluso Event Jobs Done, each of you that signed up will get contacted with the final price 

John Mentionned also intersting transfo to try for this project, his own brewed BV11T and T14   if your intetested drop him an email,  the cinemag is a good starter but i will be testing those soon,
;D
cheers,
D

 
I ran into a few threads that couldn't identify the u87 transformer spec. then another thread on a Neumann forum which identified as a BV13, but couldn't find any info on that.  Other threads say the cinemag 10:1 is 'in the ballpark." So does anyone know what the specs are on the transformer?
 
the specification on the mouser web site is wrong if you look at the data sheet the 68M is like this,
it should be all fine 1/4 W and dimension too,
 

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poctop said:
the specification on the mouser web site is wrong if you look at the data sheet the 68M is like this,
it should be all fine 1/4 W and dimension too,

How about that 750W 60M resistor?  ;D 

Been noticing a ton of errors on Mouser recently...
 
Its seems that AMI funkenwork might have the magic transformer ,

I am working on it very hard now, :p

let you know
 
so seems that the original tran is BV13 and the BV90415  is the succesor with core grounding ,

if anyone has info on those let me know,

thanks,
dan.,
 
New Scoop

just receive an email from Tabfunkenwerk they are just to realese the new T13 wich is designed as a direct replacement of the u87 transfo,  email i received below ;D ;D

Hi Dany,

Thanks for enquiring about BV13’s!  We are about to add a new item to our website which is our T13 transformer.  It is built on the same platform as our T14 transformer but with the ratio and impedance necessary as a drop in replacement for U87’s and U87 DIY projects.  I don’t have a picture of it yet but I will be adding it to the site soon. 
The price will be the same as our T14 transformer, $95 plus shipping.  I think Oliver has a few available from the first production run that he made but I will check with him to see.

Cant wait to try this one out,


 
Awesome. Just finished one of mine with the cinemag and peluso capsule and it sounds great! Let me get the other one up and running and I'll shoot it out with my vintage u87.
 
Marcocet said:
Awesome. Just finished one of mine with the cinemag and peluso capsule and it sounds great! Let me get the other one up and running and I'll shoot it out with my vintage u87.

Great Marcocet  ;),  i really hope you enjoy the mike keep me posted as per your findings,
D.
 

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