muff fuzz problem

[nokaster]

i tried my luck at the other forum, but there isn't much interest in the muff fuzz i guess.
maybe you can help me here?

so i built a muff fuzz and i'm not getting it right...
it works as it should, but different IC's give me different problems:

4558, 1458, 072 = no sustain, notes just abruptly velco out
353, 358 = sustain, nice tone, but lots and lots of hiss

where did i go wrong?
i used andrew carell's vero layout.

[foxfire]

your best bet is to read and follow this, http://www.diystompboxes.com/smfforum/index.php?topic=29816.0.

[Gus]

I just checked the other forum you got an answer at the other forum.  Different chips do different things in that circuit.  It might be fine did you ever hear a real one?

Does the layout match the real schematic?

No interest in the cool muff fuzz?

  I think you need to look in the schematic section and do some searches here.

[WGTP]

Gus did some nice mods to it.  If you want it to act like a standard distortion, add a 1meg resistor in parallel with the diodes.   

[electrobuster]

I had to use a TL072 when I built mine with the same layout. Also preferred in914 diodes as well.
With a TL072 mine gates in a cool noise gate kind of way.

[oldrocker]

I've built both the op amp and transistor version.  They sound very different from each other but I prefer the transistor version of which I've built two.  I have the same gating issue with my op amp Muff Fuzz and I just excepted that as the nature of the beast.
http://fuzzcentral.ssguitar.com/schematics/mufffuzztransschem.gif

[WGTP]

http://www.generalguitargadgets.com/diagrams/gus_muff_mod1.gif  I like this one.   

[Gus]

Also if using it for bass try a 470K feedback resistor for the 1 meg position  at the first stage. The reduced gain sometimes work better with bass.  I tend to like it without the red added 220pf and .1uf caps. 
The opamp used does seem to matter with this circuit.  Think about input pair current with different types of opamps.

[WGTP]

http://www.aronnelson.com/gallery/v/WGTP/AlteredMuff.jpg.html?g2_imageViewsIndex=1

Here are some variations with different clipping circuits.   

[Dragonfly]

Gus did some nice mods to it.  If you want it to act like a standard distortion, add a 1meg resistor in parallel with the diodes.   

+1.

I even left room on the vero layout to do exactly that !