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.