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I can confirm that Dailywell are very good. Nothing wrong with them.

Yes, but I believe @thunderaxe is planning to use that extra opamp for something else eventually. And in this particular, simple circuit, there's no real benefit from an opamp-buffered VREF, since nothing draws or sinks significant current to/from it.

C2 in Sour Grape will help reduce ripple to some degree, depending on the output impedance of the power supply. The "stiffer" (lower impedance) the power supply, the less effective is C2 at filtering. If you look at R17 in Dream Fuzz, its main purpose is to help with PSU filtering when combined...

That's on the Dream Fuzz. I was talking about Sour Grape. My bad, I forgot to mention it.

Just wanted to point out that the R7/R8 divider will dump whatever noise/ripple there is in the AC power supply straight into the op amp input. Why not simply tie pin 5 to Vref through a resistor?

The unused op-amp could have been put to good use as a rail splitter, I suppose.

I did, and got really really drunk 🤣

I forgot about the thermal camera, it's been a while since I used mine. Great troubshooting tool if you have one.

Did you ever have to find a power short circuit on a board with dozens, if not hundreds of little power decoupling caps all over the place? And they all look fine! How do you find the culprit? Wherever you measure across power, it's a dead short. Or is it? Not if you use a milliohm meter...

I actually prefer soldering (and desoldering!) SMD parts to through hole. With the right iron (I use old Metcals), tweezers and a magnifying glass lamp or goggles, it's a piece of cake. I'm 53 btw, with the usual eyesight issues, so it's not just a young person's game.

Here's a selection: https://www.digikey.ca/short/h3q4zrpj

100v rated X7* will work well just about anywhere in a pedal powered by 9 or 18V. They'll likely stay within +/-10% through any temperature change or voltage that a pedal is likely to see. Just don't use them where a tighter tolerance is needed (5% or less).

Circuits with PNP transistors usually use a positive ground because PNPs are biased the opposite way of NPNs: their base and collector need to be more negative than the emitter. Since the emitter is usually common between the input and output, we call that node the ground: the common potential...

I asked and she said she always prefers a hard cl ick. Whaaat? Did I make a typo?

Well, depending on what comes before, the extra noise may or may not make a practical difference. If it comes after some gainy pedals, then there might already be enough noise baked into the input signal that a bit more doesn't matter. But it's good to know that non-inverting is always less...

Only if you don't mind the major extra noise. Here's the difference between inverting and non-inverting unity gain buffers, both with a 1M input impedance:

Not sure why you're using an inverting configuration for the input buffer(s) (IC2). As shown on the schematic in post #3, your input Z is 50k (R13||R14), which is way too low if you're going to plug a guitar straight into BLEND_IN. Also, the buffer noise performance is significantly degraded...

It drops the 68V to 37.8V.

I thought about it, but I'd like it to be self-contained, power and all.

I really did not have this in mind when I made the little PCB, but it seems to fit in an inline 1/4" female Neutrik! How convenient. I did have to cut some PCB corners, no big deal. One tiny "detail" remains: how do I power the damn thing?? Use a TRS cable with the ring = +9V? Too convoluted.