Your favorite Big Muff mods?

[null.fuzz]

I'm about to embark on a project that basically involves reviving a guy's Russian Muff. While I'm at it I've been give the freedom to mod it pretty much any way I want - the only problem being that there are so many options I can't really decide where to start! "Big and fuzzy" are my goal.

What's definitely on the list:
1) Diode switching for the 2 clipping stages
2) Tone control modification (remove the mid-scoop) and bypass

What might be on the list:
1) Replacing transistors w/ higher gain versions
2) Noise gating
3) Footswitchable gain control for 2 independent settings
4) Clean blend

So what mods do your Muffs have, and what do you think about them?

[devnulljp]

I did the noisegate mod to a 3034 muff -- banged a 100k trimpot parallel to the resistor to ground at the second gain stage because it was really noisy, but it was also kinda fun to make a muff sound like a Maestro
Other than that, try pulling these two 0.047s and replace with 1uF ceramics to kill the boom.



...but then you know all that (and more) already I'm sure...

[null.fuzz]

I did the noisegate mod to a 3034 muff -- banged a 100k trimpot parallel to the resistor to ground at the second gain stage because it was really noisy, but it was also kinda fun to make a muff sound like a Maestro
Other than that, try pulling these two 0.047s and replace with 1uF ceramics to kill the boom.

Cool idea, noise gate has moved up on the list. I was thinking of using a switched pot so the gating could be turned off completely if desired. Awesome picture as well!

...but then you know all that (and more) already I'm sure...

Not yet. I grabbed some schematics and have been going through it on my own. I've seen a bunch of lists of mods but need to collect and summarize them for myself.

[nbabmf]

Here are some of my favorite mods:

- Transistor swapping - if you're doing this on a Russian, just about anything with hFe 300 or higher would be better. Try 2N5088/9 or BC 548/9. You can also use germanium transistors but you'll have to deal with biasing them.
- Germanium diodes in the first clipping stage (thicker, more compressed) and LEDs in the second (brings the overall output back up because Ge diodes cut output a little)
- Toggle switch for tone bypass
- Replacing the input, output, and coupling caps with tropical fish caps (I like 1uF for input and output, 0.1uF for coupling)
- Increase the value of the caps in the feedback/clipping to tighten things up

[Scruffie]

My favourite was removing the first clipping stage entirely (use a DPDT toggle) turns it into something resembling the Colorsound Jumbo Tonebender, nice and open and fuzzy rather than the thick sustaining sound we all know.

Another good mod is putting in a Baxandall style tone control, the pedal is really great with Bass & Treble Controls, I did the flat mids switch though and that was pretty nice too.

And for me... the creamy dreamer really wasn't that dreamy... wouldn't reccomend it really. Also... I tried transistor swapping, I put in MPSA13s (ultra high gain transistors) in the first and last stage and could I hear a difference? Not really... wasn't worth it for me, the pedal either has lower gain transistors or after a certain point of hFe they all saturate the diodes at the same point anyway.

[nbabmf]

My favourite was removing the first clipping stage entirely (use a DPDT toggle) turns it into something resembling the Colorsound Jumbo Tonebender, nice and open and fuzzy rather than the thick sustaining sound we all know.

I did this with a Russian Muff but it wasn't quite right. There are a few other things that need to be done to get the best of both worlds, otherwise it's just a woofy mess.

I tried transistor swapping, I put in MPSA13s (ultra high gain transistors) in the first and last stage and could I hear a difference? Not really... wasn't worth it for me, the pedal either has lower gain transistors or after a certain point of hFe they all saturate the diodes at the same point anyway.

The first stage is a buffer and the last stage is a recovery stage to remedy the signal loss in the tone stack, so it makes sense that you really couldn't hear a difference. I'd imagine that pedal was probably a little louder though. If you change the transistors in the two clipping stages, you will definitely notice it.

[Scruffie]

I did this with a Russian Muff but it wasn't quite right. There are a few other things that need to be done to get the best of both worlds, otherwise it's just a woofy mess.

Didn't come out a woofy mess for me at all, quite pleasent distortion, but perhaps I just got lucky, doesn't take a second to just lift them and try it though anyway, don't like it, stick them back in.

The first stage is a buffer and the last stage is a recovery stage to remedy the signal loss in the tone stack, so it makes sense that you really couldn't hear a difference. I'd imagine that pedal was probably a little louder though. If you change the transistors in the two clipping stages, you will definitely notice it.

Sorry, I missed the word clipping when I said stage, that's where I tried them, not alot in it for the high hFe of the transistor, for me anyway.

Coincidentally the first stage isn't a buffer, it's a booster, so even if I did use it there, it should have had an effect.

The Big Muff is a much more complex beast than it appears anyway... it doesn't really leave itself open to simple modding, well it does... but it doesn't.

[nbabmf]

The diode lift sounds good with some amps, not others. It was awesome with my Valve Junior but sounded terrible with my Carvin. I need to play around with it some more to get a usable sound on both sides. A Supa'd/Jumbo'd Muff usually sounds better one way or the other, but not both as far as my experimentation has gone.

Also, you're right, it is a booster. My bad! hFe is only part of the picture. The collector and emitter resistors determine a lot, as well. I have found that the overall character changes with different transistors but only in the clipping stages. If you want to get more out of it, you've got to mess around with the gain factor. The Creamy Dreamer mod basically maxes out the gain factor, which sounds like shit if you ask me!

Here's a really good read on the topic:
http://sovtek.webs.com/bmpgainfactor.htm

[Scruffie]

Ah makes sense, could be said for alot of equipment though, but it's something to try atleast, I only tried it on a practice amp.

Yeah hFe is only part of the picture (which is why I said the muff isn't open to simple mods) then again... at an hFe of 10,000ish... thought it'd do a bit more for the pedal, I had a switch wired up to take all the emitter resistors out aswell at the same time, it kinda worked with that but.. still mainly the same sounds at the top end, backed off the gain it changed things a bit but then.. why not just turn the gain up.

It wasn't for me is what i'll say... a germanium muff like you built I could understand sounding fairly different to your standard big muff but not even big muffs sound like other big muffs, alot of the tone comes from the tone shaping rather than the circuit itself so I like either the tone stack disengage or the Baxandall tone control on it and removing the diodes was something that gave a drastic "yeah I can certainly hear the difference" sound compared to most of the other little mods, i'm not saying they changed nothing, i'm just saying... pff

[deadbeatriot]

my personal favorite is a simple tone bypass switch. it's super simple and adds an entire dimension of usable tones

[null.fuzz]

Thanks for the input!

And nbabmf, stop reading my mind.

- Transistor swapping - if you're doing this on a Russian, just about anything with hFe 300 or higher would be better. Try 2N5088/9 or BC 548/9. You can also use germanium transistors but you'll have to deal with biasing them.

Swapping the transistors out for 2n5088's was my first step.

- Germanium diodes in the first clipping stage (thicker, more compressed) and LEDs in the second (brings the overall output back up because Ge diodes cut output a little)

Damn it! Also one of my goals. I'm thinking about some DPDT center-off switches for Si/bypass/Ge in the first stage and Si/bypass/LED in the second for a bunch of options.

- Toggle switch for tone bypass

I think I'm going to go one further - add a switch for mid boost (or at least flatten) and allow for total bypass.

[McSpunckle]

Pierced clitoris.

And the "Tone Wicker", which just removes those little high roll-off caps from the first 3 transistor stages.

But mostly pierced clit.

[Teej212]

you could add a floop to make siren noises!

[McSpunckle]

you could add a floop to make siren noises!

Or, like, an envelope controlled floop to make controllable Nintendo sounds!

... actually, back off, you vultures. I thought of it first.

[Jero]

you could add a floop to make siren noises!

Or, like, an envelope controlled floop to make controllable Nintendo sounds!
... actually, back off, you vultures. I thought of it first.

Haha, let's hear it...first person to post a vid wins