Menatone - none more black BIAS?

[motterpaul]

Do you want to bias to 9v? (half of 18v after charge pump?).

I built the resistor version with J201s and the bias settings are all over the place.

[Travis]

Generally half the supply voltage is a good starting point, but it's best to fine tune by ear.

Your supply probably isn't putting out exactly 9V, and your charge pump probably isn't putting out exactly 18V, so rather than arbitrarily biasing to 4.5V or 9V respectively, you could simply measure the actual voltage that is present in your supply and divide it in half

[motterpaul]

I did get it to sound pretty decent with the recommended settings, but if I had it to do over I would have used the trimpots.

J202s are far more predictable so set resistors would work, J201s are different. I should have thought of that before I jumped in.

[music6000]

Hi
   If I want to used Fixed resistors in my builds, I use  external  loose TEMPORARY 16mm potentiometers and set the suggested resistor value across Lug 1&2 if known, Fine tune to Suit Circuit & remove the Temporary leads & measure across the Lugs 1&2 with a Multimeter & replace with correct value resistor, the advantage is you use less real estate than Trimmers would do.

Cheers music6000

[motterpaul]

FYI - I rebuilt this with trimpots and the bias is really crucial to this build. The pallette of tones is huge, but noise control is also an issue.  The pedal sounds really good; tight and with tons of sustain, but with headroom and not squishy at all (when biased right).

I now understand what the "suck" control does - it gives you that sound of a super high-gain tube amp when you turn the pre-amp gain so high that notes actually compress to the point where even the attack disappears. But once you get whole circuit biased right you can get the "suck" control to add the critical amount of gain that makes this pedal sound "tubish" without it going overboard on the compression.

In the fixed resistor version I found that I could just barely crack the volume on and it was full loudness. That has a lot to do with the bias of Q1, which should be almost as close to 18v as you can get it with the tradeoff being tone vs noise. In other words, if you crack the trimpot on (dialing down from 18v) you get the right tone but it comes with noise. I couldn't find a way to dial out the noise on another trimpot, either. But I did find that with #1 set for tone + minimal noise that the volume pot responded normally, not coming on full just by barely cracking it on.

Nice pedal in the end, worth the effort. Just wish I could tame the noise a little more.

[motterpaul]

BTW: I should have mentioned the fixed resistor version has recommended voltages, and they are not generally 1/2 the supply voltages. I should have just looked at those for a starting point.

It's one of those builds where if you don't have all the trims close you might not hear anything so you can't even be sure it is working, but once you find the tone it is easy to dial in the rest of the trimpots - the trick is to start with trim #1. (the top/right one, I think it is #1).