Big Muff Pi's (opamp version) sustain pot question

[gigimarga]

Hello,

Looking for something on my balcony (my DIY warehouse) I found a Big Muff Pi (opamp version) which i'd built in the summer.
After trying it, i've start to like it more and more, but i saw that the Sustain pot have a little effect (too much distorstion when the pot is at minimum).
Searching the forum i found a mod by analogguru (you must to put the 47 ohms resistors from the lug 1 of the sustain pot directly to ground and to insert a 10uF at the lug 3), but i tried it and it had a little effect too.

All that I want is to have less distorstion when the Sustain pot is at minimum, like in the transistor version.

Thx a lot all!

[km-r]

post a schem?

maybe lower the feedback resistors of the op amp stages before the clipping stage...

[gigimarga]

Sorry...i forgot about the schematic...http://gaussmarkov.net/layouts/opbmp/schem.png...if i remeber right i used the gaussmarkov's project...the mods are from analogguru's site...

Thx a lot!

[gigimarga]

No suggestion?

[gigimarga]

 

[gigimarga]

nobody has an ideea about how to make the sustain pot more usable?

[gigimarga]

 

[Pedal love]

The 470k resistor in the feedback loop of the clipping stage. Have you tried lowering this resistor?

[gigimarga]

Thx Pedal love for your answer...I don't want to have less distortion because i like it...i want to have a larger adjust from the sustain pot...now, it's a little difference between the min setting and the max setting of it...when the pot is at min i want to have an almost clean signal (as in a thousand of distortions...) and with the pot at maximum i want to have the original distortion ...excuse my english, please!

[slacker]

If you want less gain with the gain pot turned down then make R8 smaller or replace it with a jumper.

You won't get a clean sound doing that though because the first 2 stages have a gain of about 60 so the sound is already distorted before it gets to the gain pot.
If you want a lot less gain try making R3 smaller something like 100k might help.

[Pedal love]

Slacker is right. Just looking at it there is a lot of gain before the sustain control. Maybe parallel it with a box that isn't very distorted?

[gigimarga]

Thx a lot both of you, slacker and Pedal love!
I will try to replace R8 with a jumper...i don't try this because of the C4...i did't see before this configuration...and maybe i will replace R3 with a 470K pot