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... it destroys the original full quality.

Well, that's the whole purpose of a fuzz, ain't it?  That said, I don't expect that anybody can hear the difference between carbon comp, carbon film and metal film resistors in a fuzz face (at the same resistance value).

This will depend a lot on what exact reverb tank you have lying around, especially the input/output impedance. Some tanks are meant to be included in tube circuits (with a transformer), and others are meant to be driven directly by opamps. Mixing that up will lead to drama  .

They at least differ in resistance and max. current rating, judging from the datasheets.

I've been testing without a box (just a simple alligator clip testing rig), so I don't expect it to be completely noiseless, but I didn't expect that high pitched noise either lol

This could be the cause of the problem ... a non-perfect connection to the power ground may imply that any 'pollution' of the ground can creep into the audio parts of the circuit. Therefore, the problem may disappear when you box the circuit properly. However, that is risky, of course. What I sometimes do is to make a mock-up on a piece of hardboard: drill all the holes for pots/switches in the correct relative positions, and add jacks and power connector to the same piece of board. That allows me to wire everything neatly, without having to drill/finish an enclosure.

As i said, it goes quiet with an SHO in front, but stays noisy with ic buffers in front... maybe a mosfet buffer would help? I'm really just guessing.

That's weird ... I would have predicted that an IC buffer would work better than a mosfet booster ... Well, another case where my my intuition fails  .

But, what did help is a capacitance multiplier before the inverting stage on the board, now the squealing noise appears only when every pot is almost maxed out. I might try and adjust the corner frequency later today to see if i can completely eliminate the noise.

You mean low-pass filtering of the signal in the circuit? Would be a pity to sacrifice highs if its not really needed. Unless you don't like highs anyway, of course.

Given that powering by battery doesn't help, and neither changing ICs (and IC types) for the charge pump ... my guess would be that the issue is with the layout on the stripboard, or with your wiring. If others did not report such issues with that layout, wiring would be my prime suspect. Either the grounding is not optimal/effective, or the power, or there is a proximity effect from the input wire being too close to other wires or components (or some components being too close) ... How are you testing the circuit at the moment?

Sometimes putting a (buffered) pedal before the affected circuit helps. Not sure why that should be so; I can only imagine that it's an impedance thing  .

The resistance of an inductor will usually be quite a bit less than 47R. This circuit will help when the noise comes from the power supply (and it will be really effective), but things like whine/squeal will usually come from the effect circuit itself ... and then you'll need a different strategy.

Looks good to me  . The link you posted says "Component values are not critical" and used 330uH. I found 100uH advised somewhere else, and VFE uses 1mH. So that seems a reasonable range. I always use MLCC for the 100nF, but film is probably fine as well. I would choose the value of C1 based on how much ripple I expect, and how much current would be drawn. For most pedals, 100uF would be fine, but for an entire pedalboard, I would use something larger. However, my 'knowledge' all comes from scouring the internet for info and schematics, and my own experience ; I don't have the electronics background to make really intelligent statements here  .

I used inductors of 100uH with great success as filters for generic switching power supplies. These are pretty cheap, deliver lots of current, but are by themselves way too noisy for pedals. Inductor plus big cap plus mlcc 100nF cap solves that (plus a regulator, depending on the power supply). Only thing to watch out for is the max current rating for the inductor. That way, I've been able to use various power supplies I had lying around the house.

If you have a deluxe pedal-specific power supply, you won't need this. Which is probably why most circuits don't include it. I just bought a nice pedalboard batterypack, and that also needs such a filter (the battery itself should not be a problem, its probably the circuitry for switching the thing on and off that's causing noise issues with, especially transistor-gain based, pedals).

Note that, in the classic Fuzz Face circuit, the fuzz pot is wired as a voltage divider, not as a variable resistor. In this circuit the pot offers a constant resistance to ground for the transistor, plus a variable boost from the bypass cap on the wiper. Changing the value of the pot will change the resistance to ground and thereby more than just the 'spread of fuzz on the pot'. This is DIY, so do whatever sounds good to you, but if you like the sound with 1k to ground there, you should look at the taper of the pot and not its value. For the Fuzz Face, 1kC works best but you'll still have all the 'good sounds' at the last part of the sweep.

Of course, if you want to get fancy, you could put a 500R resistor in series with a 500R pot (connect fixed resistor to ground). That leaves a constant 1k to ground, but the pot will cover the interesting part. Or just forget about the fuzz pot and wire a fixed resistor with the cap there, and use the volume knob on your guitar  .

Old school fuzzes may not be so loud, though generally more than unity, with regular passive guitar pickups. But the LM is really loud, in my experience.

Fuzzes don't have a general output level  . Depends a lot on the circuit, and in several circuits also on the choice of transistors and the biassing scheme. I have a Lunar Module Deluxe clone at my pedalboard right now and it is loud as hell (with the fuzz knob almost maxed, still more than unity with te fuzz knob at minimum). You may need to do some debugging ... 

Long answer: no. Which specific fuzz circuit is it?

Anyway, I will be looking into it and I still plan on taking May off to get the new store/website designed to work with ShipStation or Stamps so it may come back.

Thanks, much appreciated.

Any chance that we'll see "Flats shipping for international" returning any time in the near future?

The sweet spot for transistor gain is pretty well established for the Fuzz Face circuit and part of the problem with silicon versions of the circuit is that it's difficult to find transistors in that 80-100 or so hfe range.

Well ... if something gets repeated on the internet over and over, that does not make it 'true' ... it does make transistors in a certain gain range difficult to find and expensive . I have been playing with some left-over transistors with very low gain on a breadboard FF, and can get some nice sounds out of them. Some people have reported good sounds with high-gain silicons, you may have to tweak some values. So, if you have a set of transistors that are higher or lower gain than traditional wisdom prescribes, I would simply try them and see if you like the sound.

There's also the option to combine two high-gain transistors to form one low-gain one ... I will try to look that up. And, there are silicons that have low to very low HFE. They are just a bit more difficult to find.

Edit: it is called "piggybacking transistors"; with google you'll see more about it.

Shouldn't it be possible to adjust the gain of Q1 with a potentiometer in series with the emitter and ground? Every version of this circuit I've seen just ties the Q1 emitter straight to ground. It seems like being able to adjust the gain with a pot would make it much easier to dial in a good sound without need to test a whole bin of transistors.

Surely that is possible. The Aion Solaris FF has a trim pot there for people to play with. I tried it on my breadboard version, and did not particularly like the result with the transistors I tried, but YMMV.