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I'm just wondering about people's experiences with 9V pedals and unwanted clipping.
I've built a voltage-doubled clean boost with an op amp buffer at the beginning of the signal.... sounds really nice.
I'm thinking of removing the doubler and keeping it at 9V but I've yet to try a variety of guitars through it at 9V.
Has anyone experienced unintended (harsh) clipping from particularly hot pickups in 9V pedals (clean boosts) that don't use voltage doubling, and do you think it's a good idea to stick with 18V or do you think 9V is good enough in the majority of scenarios?

Thanks....

Hi all, I've put together this volume/boost design meant to be used in a volume pedal enclosure.
It sounds good to my ears but I would love to hear any advice about improving the design in any way.
The things I want to keep the same:

The Volume treadle pot is A250k
There is a Max pot that sets the volume ceiling when Volume pot is fully clockwise
There is a decent amount of clean boost available

Thanks

This is a great sounding effect. I've been playing around with the various pots and trimpots and to my *imperfect* ears, in the vibrato mode, the amount the pitch is modulated is, let's say, a semitone. So, the signal warbles up and down a semitone and it seems that the Intensity knob attenuates the amount that the semitone warble is heard, but it doesn't change the amount that the pitch changes, if that makes sense. Adjusting the internal trimpots, to my ears, also don't change the amount that the pitch changes, they just alter how pronounced or audible it is.
So, my question is: am I wrong about this, and if not then what specifically could one adjust to control how 'far' the note is bent? Is there a practical way to have a knob which can expand or contract the amount of pitch bending, so as you turn it clockwise the warble increases/decreases in pitch?
I hope this was clear, thanks in advance....

I have a circuit which, with 9V, draws around 31mA. I've been using this voltage 'doubler' (image attached) with a NE555P chip to bring the voltage to 15.9V and the current to 75.5mA.
It sounds fine, no issues I can detect, but I don't have much experience using doublers so I'm curious if this looks like a good circuit to consistently use with that amount of current.
I'd likely use an SMD version of a 555 chip based upon availability.
Thanks in advance!

I'm looking for recommendations for quality SPDT toggle switches. I have a few Taiway on hand... opinions?
Also wondering about opinions on good quality 4PDT stomp switches, preferably with a soft click but not totally necessary.
Thanks

I was having issues with a parallel looper design and asked for advice a while back to help eliminate switch popping and circuit noise. The attached file [SCHEMATIC_Version1] shows a pop-free version; the switch popping finally disappeared after removing all pulldown resistors. The guitar signal was too quiet, though, and the circuit had a high noise floor. Although the schematic doesn't show it, I was using a voltage doubler.
The second file [SCHEMATIC_Version2] was a redesign using lower noise op amps and other changes. The switching itself remained the same. This version has switch popping issues.
The pulldown resistors at input/output/4PDT lug 4 were added later to try to eliminate the popping but didn't help. I tried lug 6 to Vref as in Version 1 but it didn't help. The LED being removed doesn't help either. I lowered all capacitors in the audio path to 100n to temporarily hear what that did when switching the 4PDT and SPDT(Tails) on and off. There was still a significant pop when either were turned to the on position.
I should note that I used an audio probe to determine that there is *almost* no pop going through the sends, mostly through the circuit output and output jack. I added a 100n capacitor after lug 2 (not shown) and this reduced the pop when switching the 4PDT to the off position.
If there's anything else worth trying, I'd appreciate any suggestions!

I'm looking for for a solution to popping that's occurring with a 4PDT and SPDT in a circuit by potentially utilizing a microcontroller. I've read that they can be programmed to briefly mute the signal as they switch, which can eliminate popping. It's something I'd eventually love to learn how to program and implement myself but in the mean time, does anybody know of anyone with this knowledge/experience that could provide this service?

I'm looking for a supply of S-taper, 10k pots with a minimum life cycle of 100,000 rotations.
Has anyone encountered these?

I've been working on a parallel mixer with optional tails switch. I modified the switch wiring from Induction's tails mod from the All-Star Digital Reverb, and incorporated the circuit grounding of the sends/bypass from Slacker's looper.
This version is currently working, although after plugging in power there is an initial large pop sound when either the On/Off switch or Tails switch is engaged. After waiting about 20 or 30 seconds after clicking either of these switches the first time, the switches no longer pop. I'm wondering if anyone has any ideas for eliminating this popping sound. Would it be worth trying JFET bypasses?
There is also a soft hiss in the background when engaged; what I'd describe as white noise. It's not super loud but it is noticeable at loud volumes. I'd like to reduce it as much as possible.
I'm also wondering if the 330k/47k resistors in the feedback loop of U2 are too large... those could likely be reduced, keeping the 7:1 ratio?
Any other insights and feedback for improvements would be greatly appreciated... thanks!