Neumann Vintage U87 Clone : Build Thread.

[Jmaffei]

Thanks for your reply @Khron, Yes I have looked for alternative parts with similar specs, the detail I'm not sure about is the capacitor material. I assume Styroflex Capacitors have been selected for a reason, and I'm not sure what would be considered an acceptable capacitor type as a replacement. Any ideas?

 

[Khron]

I assume Styroflex Capacitors have been selected for a reason

Vintage w*nkery, more or less...

Just about any film cap (polypropylene / CBB, polyester) should be fine, as long as it physically fits.

 

[Jmaffei]

Vintage w*nkery, more or less...

Just about any film cap (polypropylene / CBB, polyester) should be fine, as long as it physically fits.

Super helpful thanks!

 

[fsalter]

Super helpful thanks!

You could use C0G / NP0 type capacitors of the same value. They are ubiquitous, and much less prone to damage because of heat.

 

[Jmaffei]

@fsalter Yep that's exactly what I settled on in the end, thanks for confirming!

Went for these:
https://www.mouser.co.uk/ProductDet...=sGAEpiMZZMvsSlwiRhF8quJDYJDbs0w51msnUe/4e5A=

Once I've finished the builds I'll post my BOM with links, quite a few parts in the original BOM are now unavailable. Could be useful for any future DIYers, in the UK particularly

 

[micolas]

Once I've finished the builds I'll post my BOM with links, quite a few parts in the original BOM are now unavailable. Could be useful for any future DIYers, in the UK particularly

Yes, an updated BOM would be useful, not just for UK DIYers but for others as well.
Thanks!

 

[Khron]

Yes, an updated BOM would be useful, not just for UK DIYers but for others as well.

Well, considering he never bothered correcting even the board footprint for that 1G resistor you're supposed to apply the calibration signal to...... I wouldn't hold my breath.

 

[micolas]

Well, considering he never bothered correcting even the board footprint for that 1G resistor you're supposed to apply the calibration signal to...... I wouldn't hold my breath.

I have to agree with you...
But still, someone competent would be useful to update some more delicate aspects for less experienced beginners (or for those comfortable, too lazy, and who want everything offered quickly and for free). Otherwise we always end up repeating the same instructions endlessly.

 

[Khron]

But still, someone competent

... And caring (enough)... But as the saying goes, one should not attribute to malice what can be explained by incompetence, but...

 

[kantaro]

Any body know if www.vintagemicrophonepcbkit.com is still active? I made a purchase about 3 weeks ago and still nothing shipped.

 

[fsalter]

He is still active, probably quite busy. I wouldn’t worry, he always comes through.
I PM’ed you an alternate contact.

 

[fsalter]

Could someone tell me if there is any way to raise the sensitivity of my 87i clone? I have 2. One has a Heiserman capsule and the other has a Maiku. Barring the fact that they sound slightly different, the Maiku has about 3.2db less output. Would inserting a low value capacitor in series with the capsule do it? ..or am i out to lunch

 

[micolas]

Could someone tell me if there is any way to raise the sensitivity of my 87i clone? I have 2. One has a Heiserman capsule and the other has a Maiku. Barring the fact that they sound slightly different, the Maiku has about 3.2db less output. Would inserting a low value capacitor in series with the capsule do it? ..or am i out to lunch

I think Maiku is darker, so the level (real and perceived) is lower.

Have you measured the Idss of the jFET?
A smaller Idss must increase the gain of the circuit.

Or you can add a simple dc/dc to increase the polarization voltage of the capsule.

Another option is to reduce the value of C3 (10pF), it will increase the output level (but it will change the character a bit)