Want more volume on 78 Opamp Big Muff

[BetterOffShred]

Yeah so like the title says, I built a 78 opamp Big Muff using the tagboard layout, the uA741/4558 and tone bypass switch.  It's pretty loud, but not _really_ loud.. is the 741 stage controlling the overall max signal being sent to the tone stack and then volume?  What options are there for boosting output? I attached the schematic that the layout is based off, and all the notes about dotted line recommendations are taken into account.



So yeah just looking to boost output volume without stacking a boost or something.  Any ideas? 

[Derringer]

I had the same issue with the one I built. It's not a loud circuit.

You could start by getting rid of R16, it's chopping of a smidge of volume and is superfluous anyway.
I think I got my volume a little more reasonable with a 500K volume pot.
A 500K volume pot will let some more low end through though too, so you may or may not like the tonal change.

Otherwise, you could try bumping R13 up, but I don't think it would make all that much of a difference since that stage is pretty maxed out. If you did bump it up, you might have to reduce C9 to get the same low pass characteristic.

Mine is a Frankensteined version of this, but I believe I did give in and just tacked a fet booster onto the end.

[BetterOffShred]

Cool man thanks for sharing.  Yeah it's fantastic tone-wise, I'm super pleased but it barely pushes my amp. I will fool around with these ideas.  Thanks again

[BetterOffShred]

I think I may just bypass the volume pot and run it straight into a Majikbox venom boost.  Then it'll have serious amp crushing power.     And jettison the superfluous 100k to ground there as mentioned above. 

[duck_arse]

in the "tone bypass" position, R18 and R19 form a volume control, set half-way. probably to match the level from the tone stack, but if you want volume over toans, reduce R18 or increase R19

[BetterOffShred]

Ok that's good information.  I would like the bypass to be a bit louder.  I'll mess that with   thanks much sir!!

[BetterOffShred]

So I whipped up a venom boost, and ran it in series after the volume pot, but instead of having the volume pot on the venom I put 2 resistors on a toggle, so you have loud and then throw the toggle and Loud AF.  Pretty happy with how it sounds.  Thanks for the  help guys