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Also, I've started Don Quixote probably 5 times and always quit around page 100.

Gabriel Garcia Marquez's suggestion is to read it on the toilet. My suggestion is to read Edith Grossman's translation, which is readable in ways that no previous translation really is.

I promise it's worth it in the end. It is THE novel -- everything from every age of fiction since is in there, and it will probably never be surpassed. The second part is also one of the most heartbreaking things in literature.

I get no sound out of the pedal until I set the gain at around four o clock.  Then I get that exagerated increase in sensitivity past that point.

Also, the volume of the effect engaged is much higher than the non affected tone?

Any thoughts?  Thanks.

Chris

This is the gain pot taper issue mentioned in the build document. Everything's bunched up in the last quarter of the turn. A reverse log is better; you can also use a linear taper and limit it to something like 700K with parallel resistance.

And there's no reasonable cure for the volume differences, not even putting the volume pot external will guarantee you unity in all settings. I suspect that the original unit wasn't really made to be turned on and off mid song. My best suggestion is to set the gain where it's best for your main guitar in your favorite mode, and then set the volume trimmer for as close to unity as you can get.

Very nice work, koky!

Thanks for the headsup on the fuzzstainer diode  I've fixed it in the 1590A layout (it was correct in the 1590B layout).

How are you planning on doing the labeling? Because burning graphics into wood looks awesome if you want to try that. Just know what you're going to say before you do it!

3PDTs are now cheaper than Alpha DPDTs, and it requires some specialized parts that aren't a whole lot of good in most other situations (like P-channel FETs, which are now expensive to boot).

Also, some bypass needs don't gain anything from millenium bypass. For example, anything where I want the bypass indicator to also be a rate indicator, I still need a separate pole.

I think the optical bypass is actually worth the extra trouble and expense, though, because the chips are still available and cheap, and it will always fire up perfectly.

Your builds always look so elegant.

Man, that's a GREAT clip.

I might try this (or Brian's suggestion). I've never been happy with the treble content on the klon circuit, but most of my tinkering has been lowering the bass content and raising the active treble cutoff.

Your enclosure work is excellent and the wiring is really great, doubly so considering how much extra you put in there.

Those are 2N7000s; the same as what you find in an OCD or Zendrive.  Nothing original, but they sound good

Although I won't dispute that they sound good, they're working as generic silicon diodes at the moment -- MOSFETs conduct in both directions, and the lowest forward voltage in each direction will dominate the sound. You can just pull one (one direction of the remaining MOSFET will be a silicon diode drop and the other will be the "special" MOSFET clipping), or get fancy and add a diode in series with both. Here's a thread with all the relevant info and instructions on using MOSFETs as clippers.
http://www.diystompboxes.com/smfforum/index.php?topic=90474.0

I populated one and then sold it because if it's size.

Thomas_H's Azabache is 1590B-sized. I really recommend that if Ronan's board is too large. The Azabache is many times the pedal that the Professor Tweed is.

R13, C13, R14, R16, and C14 form a two-pole filter. You can increase either of the 10K resistors or lower R14 and you'll cut more treble.

You can also strap a small cap from the output to ground. It'll form a low-pass filter with R21. Shouldn't be too hard to find what you're looking for with a calculator.

If you want to cut treble before clipping -- this mostly applies to transients and line noise -- raise the 470pF cap at the input.

Any of these changes will kind of dull things at lower gain settings. I'd make them switchable.

Leakage on Q1 definitely looks low to me (remember, the leakage current is providing the positive bias for which there's no resistor!), and the gains are also a little higher than I would have gone with in all three positions. That doesn't mean that you need to swap transistors, but you might need to adjust the collector resistors.

Your bias voltages will help, too. Also, resign yourself to some fartyness. It's ... part of the sound.

You can use any low gain PNP. Anything between 30 and 70 hfe will be fine.

1N696 diodes have a typical forward voltage of 0.25V-0.275V, depending on the manufacturer. Realistically, almost any germanium diode will be fine, but the following will measure close enough:
Germanium:
1N60
Almost every russian detector diode (D9E, D9B, D9V, etc.)
1N192
1N270 (may be a little high)
Any of the Smallbear generic diodes, which are mostly 1N1xx
You can also just use the 1N34A. The Fv isn't critical in this circuit at all.

Not germanium:
1N60P
BAT43
BAT85
Several other schottky diodes ...

Per

Great etches as always. Hopefully that pedal will raise soem good money for a good cause.

Those don't look anything like the anodized yellow I got from them. The one I have is more mottled and has some green in it.

since everything afterwards is basically "just" a Fuzz Face circuit

This may be true from a topology perspective, but it's not even remotely true regarding biasing or transistor selection.

Here are just a handful of differences you'll find between a tone bender MKII's Q2 and Q3 vs. a Fuzz Face:

The bias for Q2 in the MKII settles at as little as .1-.2v. Compare that with the .5V on the first transistor in the Fuzz Face. LOTS more saturation.

The proper bias for Q3 in the MKII is ~8V, as measured on numerous vintage units by several builders (Electric Warrior, D*A*M, Luciferstrip, and others). The Fuzz Central article gives the wildly inappropriate bias voltage of 4.5V for this transistor. You might get a decent sounding fuzz by doing that, but it's not going to act or sound like a MKII.

The MKII's biasing does several things: First, it's more saturation than the Fuzz Face, so there's more distortion overall, and the final transistor is closer to cutoff. Second, there is a combination of slight gating, with a slightly "sticky" attack and a more explosive sound, along with some sagging that creates bloom. This comes as much from the biasing as it does from the third transistor stage.

If you make the first stage switchable, you'll end up with a boosted fuzz face. Not a MKII.

I haven't touched on transistor selection yet.

The Fuzz Face wants the least leaky transistors you can find.

The MKII is picky about transistors and requires some leakage in all three transistors to sound right (and for Q1 to work at all).

What else? Oh right, tone shaping. The cutoff frequency of the output on the MKII is TWICE that of a Fuzz Face. (The Fuzz Face's cutoff frequency is 72Hz.) This is actually a huge part of the Tone Bender's sound, since it helps the TB cut through the mix better and tightens up the bass despite the greater amount of distortion compared with a fuzz face.

This really leaves you with a couple results:
-A great sounding fuzz face mode and a mediocre MKII mode
-A great sounding MKII and a mediocre sounding/misbiased (and possibly disfunctional) Fuzz Face mode
-Split the difference on biasing and have two mediocre modes
-Use several switches to swap out all the parts required to make both modes right.

Or ... you could just build two great sounding fuzzes in one enclosure. The circuits are tiny, you could easily get one of each in a 1590B.

I hope it doesn't sound like I'm discouraging you from trying this. But you need to consider ALL aspects of the circuitry when you do something like this, not just focus on a couple superficial changes like value of the input cap.

Any pert comp project suggestions?

Well, I'm pretty partial to my Bearhug. The library also has perf layouts for the Flatline (Afterlife), Engineer's Thumb, a couple Circuit Salad projects, ... let's just say there are a lot of compressors in there.