Neumann Vintage U87 Clone : Build Thread.

[kante1603]

;D ;D ;D

 

[dreadheaded]

they are about 30 years old and havent been calibrated probably ever!!

I apologize, I probably should have been more aware! I am looking forward to the delivery of 200 useless screws

Also pleased to report my second u87 clone is now working perfectly, I resoldered the wires connecting the 2 PCBs together and resoldered the switch and its fine, I am guessing I must have shorted the switch or something!

So it appears I have been most unobservant the last few days

 

[dreadheaded]

oh and if anyone has any use for some m1.6 screws I should have loads!

 

[patxiplg]

Yes, use the Kemets - they'll sound fine.

If you've installed the 60M resistors then stick with them - they'll also be fine. I think the 68M ones were only specified because the 60M ones were unavailable or expensive - see way back in the thread. There's no difference in sound quality.

Enjoy your build...

Thank you so much, Krumlee!

Have a nice day

 

[useme2305]

i already posted this in danny's new thread for the blue board...but i figured there are many thread subscribers here.

it's about the the 0.033uF MKP2 wimas...what's a good substitute for those?

what about these? http://www.banzaimusic.com/WIMA-FKP2-5-0-033uF-63V.html

 

[dreadheaded]

I have finally got a chance to do some serious testing with my pair, and I have noticed that one looses a LOT more signal on omni then the other one

I was just wondering how much signal we are realistically expecting to loose when operating in omni

 

[poctop]

I have finally got a chance to do some serious testing with my pair, and I have noticed that one looses a LOT more signal on omni then the other one

I was just wondering how much signal we are realistically expecting to loose when operating in omni

wich capsule do you have , loosing signal in omni is normal to a certain extent ,
is this only on side that is lower or both side of the capsule are equal,
wich build is it the blue version or the green one ,
Let us know,
Best,
Dan

 

[dreadheaded]

I have the green board and it has the beezkneez k8, the other mic does have a peluso capsule in it I have thought that could be causing some of the difference.

 

[poctop]

I have the green board and it has the beezkneez k8, the other mic does have a peluso capsule in it I have thought that could be causing some of the difference.

is the output in omni = on both side,
dan,

 

[dreadheaded]

it seems equal in output on both sides, its just way lower then either figure of 8 or cardiod and way lower then my other 87clone which has a peluso capsule, I am just going to have a little probe around with the DMM see if all my voltages are right

 

[dreadheaded]

when I switch to omni the readings I get from R4,R5 and either side of the capsule seem odd, on cardiod and figure of 8 all 4 are showing 38v or there abouts, when I switch to omni, it drops to 6v

 

[poctop]

when I switch to omni the readings I get from R4,R5 and either side of the capsule seem odd, on cardiod and figure of 8 all 4 are showing 38v or there abouts, when I switch to omni, it drops to 6v

since you have a working mic ,
check to make sure the diaphragme is not sucking in omni mode,
and also make sure your backplate on the K8 are indeed isolated from each other ,
i have heard of this problem before on the K8
Best,
DAn ,

 

[dreadheaded]

interesting, it seems the backplanes are not isolated from each other!

 

[poctop]

interesting, it seems the backplanes are not isolated from each other!

There you go  ,  Contact Ben he will take care of ya.
Best,
Dan,

 

[dreadheaded]

Thanks very much Dany!! not only for the project but the great support too!!

As a side point, this sort of issue shouldn't affect its preformance in cardiod should it? I presume it means that only omni doesnt work completely, and I guess it explains why figure of 8 sounds so different on both sides of the capsule!

only its significantly darker than the one with the peluso capsule

 

[poctop]

Thanks very much Dany!! not only for the project but the great support too!!

As a side point, this sort of issue shouldn't affect its preformance in cardiod should it? I presume it means that only omni doesnt work completely, and I guess it explains why figure of 8 sounds so different on both sides of the capsule!

only its significantly darker than the one with the peluso capsule

it will not affect the cardiod ,
let me know how the peluso compares to K8 then ,
D

 

[dreadheaded]

i am actually doing a test recording tomorrow both of them will be up against a u87ai (cant find anyone who wants to lend me a original ) Ill grab some samples and post them up here

 

[dreadheaded]

I will post up a few samples of the testing we did today but I bounced the wrong files it seems so the audio will have to wait till tomorrow but heres a quick shot of the initial mic set up, it did actually change slightly but it shows how we approached getting the same source out of all 3 mics.

I kind of wish I had non shock mounts actually for the STY 2 body, although the neumann shockmount actually caused more problems in this set up then the STY2's when it ended up on its side, it kept slipping and the other 2 were solid the whole time, and the clone is quite a lot heavier then the AI too

 

[fazeka]

Hi All,

I'm getting very close to finishing my mic. However, I have what I suspect is a wiring issue with the capsule and having some difficulty understanding how to troubleshoot...

I first wired up the capsule and got very low output on figure-8. Omni and cardoid were adequate output. FWIW, I am using tskguy's (Eric's) capsule.

So then I disconnected the backplate wires from the PCB as I figured I got them crossed.

Soldered one of the backplate wires back to the other BK terminal on the PCB and then tried the mic. OK, I get omni with adequate output. Cardoid and figure-8 are identical sounding, also with adequate output (slightly more than omni, FWIW). Figured I'm on the right track, I solder the other backplate wire to the remaining BK terminal. At this point, the backplates are wired opposite to what they were initially. However, the mic sounds exactly the same as it did initially with very low output on figure-8.

Can't think of what else to try next. Any guidance appreciated.

Thanks,
Chris

 

[poctop]

Hi All,

I'm getting very close to finishing my mic. However, I have what I suspect is a wiring issue with the capsule and having some difficulty understanding how to troubleshoot...

I first wired up the capsule and got very low output on figure-8. Omni and cardoid were adequate output. FWIW, I am using tskguy's (Eric's) capsule.

So then I disconnected the backplate wires from the PCB as I figured I got them crossed.

Soldered one of the backplate wires back to the other BK terminal on the PCB and then tried the mic. OK, I get omni with adequate output. Cardoid and figure-8 are identical sounding, also with adequate output (slightly more than omni, FWIW). Figured I'm on the right track, I solder the other backplate wire to the remaining BK terminal. At this point, the backplates are wired opposite to what they were initially. However, the mic sounds exactly the same as it did initially with very low output on figure-8.

Can't think of what else to try next. Any guidance appreciated.

Thanks,
Chris

If you are working on the Blue Version of the pcb you should adress your question in the other thread for this one ,
I have posted in the opther thread for this one.


Dan,