Fuzz face excessive gating

Started by St_Alphonzo, November 11, 2017, 10:11:32 AM

Previous topic - Next topic

St_Alphonzo

Hi, I'm new to the forum. Just finished my first pedal build recently, (a fuzz face clone) so forgive me if this is a simple question.
I'm liking the sound of it, but there's way too much gating, a lot of the high notes/sustain gets cut off unless there's another pedal in front boosting the signal.
Adjusting the bias trimpot hasn't seemed to make any noticeable difference.
It's built from this pcb/design: http://www.diyguitarpedals.com.au/shop/boms/Facemaster.pdf
http://www.diyguitarpedals.com.au/shop/boms/Facemaster_schematic.pdf
Also probably worth noting, I used a 30k bias pot, 2.5k fuzz pot, and the transistor values are Q1: 86hfe, 34ua leakage, Q2: 131hfe, 34ua leakage.

Is it a matter of swapping out the trimpot for a higher resistance one or should I try changing one of the resistor values?
Any help would be much appreciated

Electric Warrior

Could you measure voltages on all transistor leads, please?

GGBB

If you don't have a 1k fuzz pot, try paralleling the fuzz pot with a 1.8k resistor (between pin 1 and 3 or Q2 emitter and ground). Or try lifting fuzz pot pin 1 and adding a 1k resistor between Q2 emitter and ground. Either of these should fix any Q2 bias range problem.
  • SUPPORTER

Plexi

Welcome  :)

Which transistors are you using?
To you, buffered bypass sucks tone.
To me, it sucks my balls.

amz-fx

The 2.5k fuzz pot is setting the bias too high. Either get a 1k pot or parallel it with the 1.8k resistor as GGBB suggested.

Best regards, Jack

Mark Hammer