SOLVED JCM 800 pedal issue?

[Quentin]

I have a question regarding a M800 pedal I’ve built. My pedal works but I have a sound issue I’m not sure about. Ive used MMBFJ201 jfets in my build and have tested them and they work. The issue I have is when gain on the pedal is rolled down it’s sounds more like a fuzz than a distortion. I’m also noticing that when I play and hold a note that the sustain drops in volume and then looses all volume. I hope I’m explaining this well enough. If you have any ideas or tips it would be greatly appreciated.
Thanks.

 

[Fama]

Which pedal? Schematics? Pics? Are there trimmers for the J201's? How did you bias them?

Edit: Right, M800 wasn't a typo, it's this one I assume https://www.pedalpcb.com/product/m800/

Total of six trimmers, how did you bias them? I think generally you want to bias J201's at half of the voltage, so probably 4.5V in this case?

 

[joelorigo]

Regarding the bias on this, on my M800, I got them as close to 4.5v (except Q6 if I remember correctly) as I could, and tried it out for a while. The trimmers were very sensitive and hard to get an exact number. Then I messed with each trimmer and didn't hear anything I liked better so I got them all back to as close I could to 4.5.

 

[Quentin]

Which pedal? Schematics? Pics? Are there trimmers for the J201's? How did you bias them?

Edit: Right, M800 wasn't a typo, it's this one I assume https://www.pedalpcb.com/product/m800/

Total of six trimmers, how did you bias them? I think generally you want to bias J201's at half of the voltage, so probably 4.5V in this case?

I found that I did have 2pm the JFETs that were outside the proper bias voltage. I replaced some resistors and adjusted my trim pots and all was good. Thanks for the help.