Matador/Studio 939 C12 Clone with low output volume.
« on: September 18, 2020, 01:53:31 PM »
This week i've built the c12 clone using my Apex 460.

I retained the capsule (dont have the money to change now) and the transformer (it was pretty linear and usable) and i'm using a RCA tube.

Everything went smoothly. Adjusted the supply heater, bias and +B as per description (6.3v, -1.00, +120v) without any issues.

On the mic itself I got 6.1v, -0.8 and +119) not too far from specs.

But the output volume was very low.

So i thought it could be the low +B. The original circuit i think worked around 180-190v, so I altered the pots to get 6.3v on the tube (6.5v from PS), and went to max I could get from the PS (152v), receiving around 150v on the mic itself.

The volume improved a lot, but still a 'quiet' microphone. Should work fine on drums but not for all types of vocals.

My question is, is it possible to go above that voltage? Any tips? Am I missing something?
Anything that is too stupid to be spoken is sung


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