SIVER MICA Caps. in T/S

[axeman010]

This is a question about silver Mica caps.

I have used 220pF micas in the GGG Boutique mod Tubescreamer (board from GGG - they really are well made boards!), one replacing the tant (C9) in the tone part of the circuit and one gain section C3.- no other substitutions other than those listed in the boutique mod from GGG.

I have measured all the voltages on the IC and the transistors and they are all OK. I have also checked all orientation of the parts and for bad joints.

When in use the guitar can be heard from the T/S and the volume control works but the signal is not distorted and the both the gain and tone pots do nothing - there is a slight change in the sound when changing the gain but its very slight.

Surely the Micas alone could not have caused these problems?

Are they a valid substitution for the tant and film caps recommended ?

Thanks

Clive.

[frokost]

Well, C3 is supposed to be 0.047 uF and C9 is 0.22 uF. 220 pF is 0.00022 uF....