adding a clean volume knob to a fuzz pedal (dod fx52)

jefkritz · #1 02-25-2013, 01:36 PM

i've got a dod fx52 fuzz pedal that i love. with tone and fuzz all the way down it has a really nice wooly fuzzy overdrive that's super fat and bassy, and it works great in my band at low volumes, but as soon as we play a little louder (aren't dynamics fun?), it completely drops out of the mix.

i want to replace the volume knob with a stacked knob for effect volume (the current volume) as well as clean volume (this would be new). this would all be within the effect (ie hopefully no effect when it's disengaged).

i was hoping for some thoughts from more experienced tinkerers before i get started, especially as i don't want to ruin this pedal. does this sound feasible? any tips / things to watch out for? alternate ideas?

i'm also looking into a separate clean blend pedal, etc, but would rather not add another piece to my growing signal chain...

El-Bob · #2 02-25-2013, 01:42 PM

I know very little about this stuff, but my first thought is that you will need more than a knob to achieve this. It seems that it would be more practical to just get a blend, or a different Fuzz altogether that has a blend control.

KCLRbass · #3 02-25-2013, 01:55 PM

Here's a nice simple clean blend circuit that you could fit on a small PCB. I don't know what the guts of DOD pedals usually look like, so I can't say whether or not there would be space. You will, however, need an active circuit in order to achieve a clean blend. A knob won't do the trick on its own unfortunately.

http://www.beavisaudio.com/techpages...BuffNBlend.gif

jefkritz · #4 02-25-2013, 10:00 PM

let me clarify my idea a bit.

what if i split the signal at the very beginning of the effect (using resistors to fight bleeding) and just sent one of the paths to the end of the effect, where i would join it with the effected signal (again, with resistors). in between would be a volume pot. it doesn't really matter that it would be a stacked pot, but it would be

whaddaya think? i feel like, aside from a slight volume drop in general, it would work. and i could overcome the volume drop with the volume knobs!

jefkritz · #5 02-25-2013, 10:06 PM

another way to think of it is having a miniature passive mixer attached inside the pedal. don't know if that helps...

also, thanks for the schematic KCLR! i'm planning to make a separate clean blend circuit even if i get this to work, so that will be very useful i'm sure

**eddododo** · #6 02-25-2013, 10:10 PM

you probably don't want to just passively combine them at the end like that..

Ill look at the schematic a little bit, but I don't play with fuzzes a lot so im not sure, but passively blending signals doesn't work awesomely, at least according to the circuitbuildinglearning Ive been doing

EDIT: its not inverting, but it still probably will not work awesomely passively blended..
Id be happy to draw up a standalone perfboard circuit/pedal to achieve it, if you end up wanting

Meddle · #7 02-26-2013, 07:32 AM

Most pedals flip the phase of the audio, so a simple passive mixer would not work.

I know it seems annoying, I thought for ages I could just put jumpers between the jacks with a potentiometer in the middle...

jefkritz · #8 02-26-2013, 07:38 AM

fair enough. thanks everyone for the input. it was worth a shot.

eddododo: if you have something in mind different than KCLR posted, i'd definitely be interested. options are always good

**eddododo** · #9 02-26-2013, 07:13 PM

Ill toss a couple ideas up tonight after work, but the circuit posted is a good one

TheBassBoss · #10 02-26-2013, 07:23 PM

http://tagboardeffects.blogspot.com/...nel-mixer.html

I'm not entirely sure if this would work, but I think it would. It's an active 2 channel mixer, so you could connect the clean signal to one channel and the effect output to the other. Again, I'm not 100% certain about this, so wait for someone else to chime in before doing this. But anyway, I hope it helps.