Arche / Fordoble boost brightness reduction

[keevohn]

I'd like to reduce the brightness of the boost side of my Fordoble (same as the Arche). I saw @HamishR's thread (https://forum.pedalpcb.com/threads/simple-fordoble-mods.15776/) about a treble snubber at the output of the boost, but I'm hoping to find another way of accomplishing this.

Can I pull one pair of diodes from the "Grit" switch and replace them with a low pass filter? If so, how might I set that up?

Thanks!

 

[HamishR]

You could do that easily. As an example, use a jumper across where D9 goes and a small cap instead of D11. Then that setting is your treble snub. You'll need to experiment on values - maybe start with a 470pF or 1nF?

Or if you want to maintain the diodes you can solder a cap on the underside of the board across pins 6 & 7 of the IC. It's best to use a socket for the IC and remove the IC while soldering. Then the treble snubber will be in circuit all the time. Or you could add the cap across the diodes on top of the board. Lots of ways!

 

[keevohn]

Thanks! I tried it with a 1nf and a jumper in place of the GE diodes. The change in brightness is only noticeable at higher Boost settings - like 3:00 and above. Below 12:00, the brightness stays pretty much the same on both sides of the switch.

This mirrors my experience with the diodes. I can't tell a difference until the Boost knob is most of the way up. That's way too much volume for me though. I'm sure there's a good reason for why the feedback loop behaves this way.

Would it be different if I socketed the 100pf cap and tried swapping values there? Might have to try.