Harmonic Percolator - make one!

[digi2t]

30mm Alpha slide pots, with straight metal lever. They're marked "Alpha". The Tayda ones match exactly.

Measured from my unit, PCB is 73.5mm X 52mm.

Thank You Sir, may i know what is the distance between the potentiometers?

Center to center of the faders is 61mm.

I'm still searching for the correct enclosure. The Hammond models don't quite fit the dimensional numbers I have here.

[zbt]

and here is the fix



diameter pot 1.7 mm, component 0.8 mm,

I tried uploading pdf format, but it was converted to png, by postimage

[digi2t]

Reach out to Theremanics regarding the enclosure. They were made in house, and the current owner of the production equipment has no plans to produce more. I'll post detailed dimensions when I have some time to measure.

[zbt]

While we deal with potentiometer, he uses it all the way up

https://www.youtube.com/watch?v=tFDp7VCDaAc

If I'm not mistaken reminds me to Ola England, but he claims to be Swedish
Mod to no knob or one knob, for neighbors' safety, and builder's insurance

He prefer use tube amp low end tend like tube overdriven
Any mod to get low end on solid state amp?

[Phend]

A year ago, I purchased (3) 2N404 from SB.
Hfe's 180, 183, 154
Plan to make another in a 1590 box similar to a Catalinbread Karma Suture.

[Phend]

The elusive Harmonic Perculator,
Just finished one, and it does "gnarl" like the so many YT's you see now.
This isn't just a slap / solder and plug in design.
So simple it is (on paper).
Page 22.... and there are more topics to consume on this beast.
My notes, before I forget what I did:
1) Select Q1 Ge PNP transistor, I used 2N404A like the old circuits show.
2) Start with a NPN Q2, have a bunch around, like 2N2222, 2N5088, 2N3565 to choose from.
3) You can fart around with the four resistor values till the cows come home. There are so many permutations, stick with the "original" R values to start with.
4) Lower the voltage to 9 v or 8.x v with a diode. (If using a PSU)
5) Now select Q2 till you get the best sounding of the bunch.
6) Play something like the first part of Black Sabbath Iron Man. Stick with whatever you choose.
7) Forget the capacitor crap, just use the correct values as shown in the original.
8 ) Start with whatever 2 diode setup up like. Change that last to taste (keeping your tongue off the metal parts)
9) Hopefully choosing Q2 will get you some "Gnarl" when pots are maxed.
10) Now replace 750K with a 4M pot or 1M and resistors to get up there (I ended w/ 3.8M) Play around with that setup until you find the "best" sound. If you don't like the "best" sound then go for the "worst" instead.
11) This is a great /  different sounding Fuzz, the Elusive Harmonic Perculator.
12) As has been said NO two are alike. (Get ready to spend hours on this project, lol)

[Rob Strand]

3) You can fart around with the four resistor values till the cows come home. There are so many permutations, stick with the "original" R values to start

LOL! indeed.

[FiveseveN]

At least one guy swapped every resistor with pots (+ more) https://www.emeraldoxfx.com/product-page/chimeric-percolator

[duck_arse]

why didn't you put your build report 20 pages ago, Phend? lucky me, I have another perco to build shortly.

[Phend]

This is what I built, Q1 Q2 750K and diodes are different (Aion's circuit).
A combination of the other schematics on this site.
At first I did not include the tone section, then added it, it works well.



Here is a video and review from :
http://thoughtfulguitarist.com/2015/07/catalinbread-karma-suture-review/

[zbt]

I'm trying to understand this circuit again, at first glance it looks like the two transistors are working in complement, one is charging and the other is discharging.

But if we look closely, it seems like they are fighting each other.

If we turn it around at a glance it always looks like an FZ1 squelcher.

because of the different phases, is it possible to make an octave?

In this way, the question again arises, does a good octave have to be clean first, then distorted, or is it possible vice versa?

[sinthmart]

Once I was interested in this effect, the percolator, but after listening to several audio demonstrations of its sound, I was surprised not by its musicality and not by its attractiveness. And I don't understand why there is such interest in this effect. Is it musical?

(musically, in the sense of "interesting", "funny", "creative" (I didn't know which word to use))

[Mark Hammer]

I've built SOOOOO many drives that they all seem to blur together after a while.  I started the thread because, after making one, I was pleasantly surprised by just how different it was from so many other things I had built and tried.  I don't know that this makes it "better", but it does have qualities that I find hard to mimic with a great many other designs that have more parts, more controls, and such.

Whether something is "musical" will depend on one's personal definition of that quality, such that what is musical for one person may not be for someone else.  The history of FX is littered with the corpses of things that appealed to a few but not to untold thousands.  So it goes.

[zbt]

for me the circuit is so strange, I like how the designer thinks, why is this and that.

Thanks to Sir Ed Giese.

And eccentric guitar players, such as Steve Albini, and also Uncle Jimi.

Also as well as members here who can explain it, who have made it, and experienced it.

 

[Phend]

Simple, want to build something different, then the HP is a great project.
But remember no two are the same !