Either a guitar problem or a Fuzz Face problem...

[colossus]

Having a weird issue here.

I just got a new guitar AND I just built a fuzz face (my first fuzz face ever). Guitar is an Agile 2000 Les Paul (my first LP ever) and fuzz face is just a standard silicon on a Madbean board. They sound great on their own but they are interacting strangely with each other. Regardless of what PUP I'm on, if I turn the guitar's tone knob all the way down, the FF suddenly gets way brighter, brighter than the FF is with the tone knob all the way up!

Wut.

It doesn't do that with my tele! I tried the FF at different spots in the chain and same deal. Agile wiring looks OK (500k pots), comparing it to LP wiring diagrams. I'm home sick today from work so I might just be having a feverish mind blank, but this seems odd. Any clue? I actually kinda like how bright the FF gets here with tone all the way down, but I'd like to know what the hell is going on...

I'll also add that the FF sounds brighter with my tele, but that could easily just be differing PUPs.

[crochambeau]

I don't think this is a problem, it's a feature. Your entire guitar circuitry feeds into the first stage of the Fuzz Face, which as I recall is straight into a BJT through a DC blocking cap. Since your pups are essentially inductors, and the tone network is (probably just a) cap to ground, you have what amounts to a tuned circuit feeding your fuzz, and a frequency dependent loading down is increasing when you dial in more "tone".

I think this sort of unexpected/non-linear operation is why some people gush on about buffers, but frankly I find this sort of strange behaviour part of the joy of doing this shit in the first place.

A buffer between guitar & FF will probably sort it if it bothers you.

[colossus]

Hmmm that makes sense, but apparently it's not just the fuzz face as the guitar is doing it just clean into the amp -- i just wasn't listening closely enough. I guess it's some sort of wiring issue. It basically sounds like it's removing both pots entirely, like pickup straight to jack. Maybe that makes sense as it only happens when vol is at 10 and tone is at 0. I'm getting new pickups next month for it so I'll probably just rewire it then too. Whoever did it did a really sloppy job.

[Dr Satan]

Sounds to me like either the tone pots are wired backwards or are reverse taper pots.

[colossus]

Definitely not backwards as the tone rolls off just until the very end of the pot where it suddenly gets bright. Weird stuff.

[Dr Satan]

Oh, weird. I misunderstood. So it's like 1 is the same as 10 on the tone control? Is that what those "no load" pots do? Or maybe it's just a weird impedance thing. FF circuits seem to be finicky as hell. They always seem to pick up Mexican, wah-O, radio when dimed.

[colossus]

It's gotta be some weird impedance issue. It's way more prevalent with the FF but I notice it with my Muff too. It's not even like 1 = 10, but more 10 - 2 are totally normal and 1 is brighter than 10. I'm not particularly bothered by it; it's actually kinda nice.

[rustywire]

Did someone possibly install a jerry-rigged treble bleed?

[eatyourguitar]

I think the pot is bad and it is lifting the wiper when turned down all the way. makes sense to me. explains everything.

[colossus]

That actually makes perfect sense and would explain why it sounds like it's being taken out of the circuit. But it's happening on both PUPs and it's a les paul, so two different tone knobs. Still certainly possible, but that'd be weird.

[eatyourguitar]

probably no load tone pots on both of them