More drive from a Zendrive?

[FingerBlisters]

Here's a schematic: https://www.pedalpcb.com/docs/Mahayana.pdf

I'm not following that entirely due to parts available. I'm using a on/off/on in the feedback loop with red/red LED, OFF, then a 1n34a/4001 pair on the other side.

I really like the pedal but would like to squeeze a bit more from it if poss. Can I change the 1k (r4) to something meatier like a 10k? I don't keep 1m pots on hand and don't want to double the gain that way, just a little bit more would be cool.

[PRR]

> change the 1k (r4) to something meatier like a 10k?

Won't change the maximum gain.

Hard to believe a gain of 470 is not enough. Triple-check everything?

[FingerBlisters]

> change the 1k (r4) to something meatier like a 10k?

Won't change the maximum gain.

Hard to believe a gain of 470 is not enough. Triple-check everything?

Yeah everything is right and works great, just needs 8% more nuts.

Out if curiosity what is that 1k doing? Sets minimum gain?

[antonis]

Out if curiosity what is that 1k doing? Sets minimum gain?

Yes..

For 8% more gain, place a 12k resistor in parallel with R3 (1k) 

[anotherjim]

I'm puzzled. Is your clipping switch in the centre off position giving a setting without any kind of diodes in the feedback? Or, is there a set of clippers always in circuit so they are effective with the switch off?
In the off position (no diodes), the output volume would be very high compared to the plain diode selection.
Is this really a question about gain or output volume level?

[antonis]

Is this really a question about gain or output volume level?

Quite rife puzzlement..

[Fancy Lime]

For more nuts, I would suggest a HiFi enthusiast forum or maybe one of the general guitar gear forums

Seriously though, I am not sure how to convert 8% more nuts to gain factor or decibels. Our ears are very non-linear when it comes to judging volume or distortion level. Generally, twice the gain factor, or 6db more sounds like "just a bit more". It you want it to sound like "twice as much", you'll want 10 times or 20db more gain. So your original post sounds to me like doubling the gain is what you probably want after all. If you don't have a 1M pot, you can also decrease R3 to 470 Ohm and increase C3 to 220nF.

HTH,
Andy

[Rob Strand]

So your original post sounds to me like doubling the gain is what you probably want after all. If you don't have a 1M pot, you can also decrease R3 to 470 Ohm and increase C3 to 220nF.

Increasing the caps is a good idea since decreasing the resistor won't end-up doing much if the cap is too small.  Who knows maybe increasing the cap alone would do what the OP wants!

[Steben]

Ooooooooooooooooooooooooor.......

You want a distortion rather than an overdrive...
Zendrive is a beefed up tube screamer schematic wise. This means it will never get that hard clipped hairy edge a distortion has.

We all know EQ is more important than anything else, but perhaps this is a perfect example of what "transfer curve desire" is.
I can be completely wrong of course, but it is what I thought about when I read "8% nuts"

Why not change the clipping to LED and LED + BAT41. That might give "oomph" already.

Or feed 18V and change to Zener diodes.