Red Big Muff sounds bad

[Erik S]

In honor of the big red big muff everyone’s talking about, I thought I’d throw this Liquid Crystal Fuzz together in a red box.

Everything works, but it sounds bad.

It’s doing some weird saggy, bloomy, sputtery stuff that I’m pretty sure isn’t right.

I pulled it back out of the box and did a component check and a careful solder inspection and everything looks okay there.

I got 100 of these cool blue-face Motorola 2n3904s from the small bear “parts for a penny” sale, and it’s the first time I tried em. So I’m a little irrationally suspicious of those.

Right now I’m thinking I’ll pull the 4 transistors, see if any of them test weird and try new ones.

Any of you muff wizards want to recommend ideal transistor specs while I’ve got the tester out?

 

[Betty Wont]

Artwork idea for big red muff...

 

[Erik S]

Well, my tester says they’re all transistors, so none are totally broken I guess.

hFE measurements:

Q1 - 229
Q2 - 196
Q3 - 136
Q4 (2n5089) - 499

Those 2n3904s are probably on the low side of in spec if I’m reading the data sheet right, but I just tested a random handful of tayda ones and they’re all right around 240, so unless someone has any more specific advice I think I’ll throw those in and see what happens.

 

[Erik S]

View attachment 107573
Artwork idea for big red muff...

Amazing.

If (when) we get one of these double-muff boards I certainly hope somebody uses that.

 

[Erik S]

Well, who would have guessed that shotgun-replacing components with no evidence they’re bad wasn’t going to fix the problem??

Put it all back together and it still sounds weird.



I think this is supposed to be one of those eqd circuits where they cloned somebody’s broken pedal that they liked, so maybe it’s supposed to sound bad?

I did go listen to some of the demo sounds on the eqd site though, and that made me think there was something wrong with mine.

Maybe I’ll try and record a demo of the weirdness at some point. I think I’m done for the day though.

 

[swelchy]

Well id rule your soldering out of the equation.. From what I can see it's freakin nice and not slathered with flux...

 

[Erik S]

Well id rule your soldering out of the equation.. From what I can see it's freakin nice and not slathered with flux...

Thanks! I’m hit or miss with my pcb cleaning, but I happened to clean that one pretty good.

Still haven’t found anything obvious wrong with it. I have a second one of these boards. I might just build that out and see what it sounds like.

 

[Fama]

It does sound a little bit sputtery to me, but I assume yours is even worse?

A couple demos I checked:

Nothing looks wrong from what I could see, but I only checked R4-5, R10-11 and R15-16, all the orientations and easy stuff like that. Soldering looks great, so my money is on a bad component or a broken trace somewhere or something like that.

 

[Erik S]

It does sound a little bit sputtery to me, but I assume yours is even worse?

A couple demos I checked:

Nothing looks wrong from what I could see, but I only checked R4-5, R10-11 and R15-16, all the orientations and easy stuff like that. Soldering looks great, so my money is on a bad component or a broken trace somewhere or something like that.

Thanks for those. Those were both good demos.

Something I failed to mention was that I’ve mostly been testing the pedal on bass since that’s where I was hoping to use it. I did plug a guitar into it for a few seconds and it sounded much more normal.

 

[Synchrony Pedalworks]

I recently struggled with a Big Muff that I was making too. I used this site to help guide my changes. From my memory, the transistors do not influence the sound as much as the other components. I had to play around with the caps to get the sound that I wanted. I hope this can help.

BIG MUFF TRANSISTORS AND OTHER COMPONENTS

PS- Love that red paint job on the pedal.

 

[Robert]

Try putting a 2N3904 in Q4 and see if you like that better.

 

[Erik S]

I used this site to help guide my changes. From my memory, the transistors do not influence the sound as much as the other components.

Great page! I didn’t do very deep research, but I did find that site in a @Feral Feline post and skimmed it. Seems like if I want to stop taking shortcuts and put the time in, all the answers are there.

Try putting a 2N3904 in Q4 and see if you like that better.

I’ll give that a shot!

 

[Erik S]

Try putting a 2N3904 in Q4 and see if you like that better.

I do like that better! It still gets a tiny bit unruly at max sustain on bass but in a nice way to my ears. It doesn’t sound broken anymore.

I’m a little worried that maybe it was cool before, and I just wasn’t cool enough to like it, but that’s a me problem.

 

[Feral Feline]

I've got a quote from Kit Rae that basically amounts to something like all the best-sounding muffs he's come across are much more low-gain than you'd think (hFE of transistors, specifically).

I'm not on my own computer at the moment so can't dig out the quote, maybe later I'll remember to look for it.