Trimmer pots in finished projects?

[analog_bham]

I am building pedals for some friends/acquaintances and they’re telling folks about them so I’m looking at selling some germanium fuzzes to some people for the first time. My tendency has been to use trimmers to establish bias then replace trims with resistors of that value. I’ve been of the opinion that a properly selected resistor shows more attention to detail but I think that’s probably nonsense. I just wondered what other opinions might be. Would you be more interested in a Fuzz Face without a trimmer or am I overthinking this?

 

[zeropluszero]

I just finished breadboarding a tone vendor mkii with trimmers, then tested it with resistors of the same value successfully. I've just assembled the components onto a PCB and am now terrified that when I turn it on its going to squeal like it did when it was not biased

 

[bean]

I am building pedals for some friends/acquaintances and they’re telling folks about them so I’m looking at selling some germanium fuzzes to some people for the first time. My tendency has been to use trimmers to establish bias then replace trims with resistors of that value. I’ve been of the opinion that a properly selected resistor shows more attention to detail but I think that’s probably nonsense. I just wondered what other opinions might be. Would you be more interested in a Fuzz Face without a trimmer or am I overthinking this?

IMO, it makes sense to use trimmers if you are trying to achieve a specific bias voltage because that value may not be a common one for a fixed resistor. This kind of ignores that bias in germanium devices will drift with temperature, though.

If you really want to be a super fancy pants kind of fuzz making guy you can actually use an external bias control that will change the bias voltage between reliable ranges, regardless of device temperature. I find that useful for FF because crushing the collector voltage down into the 3v range often produces a different attack and sustain response (also true for silicon transistors).