Harmonic Percolator

[glops]

Haven't posted here in quite awhile. Having seen cajone5's build awhile back, I really got the itch to revisit this circuit. I think the other one I had built was on a pepperspray board I etched and I built it to the Albini spec. Thought it was nice but a bit underwhelmed as it was lacking the FUZZ.

I don't have time to build much these days but spent over a month tinkering with the circuit on the breadboard, researching the old threads, etc. Settled with something close to the George Giblet schematic which I believe is the stock schematic on the pepperspray doc. Used some different values here and there but really love the way it turned out all around and now want to build more of them since its such a small parts count circuit. I even bought some slider pots for one of the future ones!

Etching the steel super fuzz style enclosure was horrible as the first attempt was a fail and had to sand it down but got it better the 2nd time around. Forgot how those really only etch to certain depth and then nothing seems to happen.

Anyways, I love this circuit. Totally beautiful and nasty at the same time. The harmonics control is pretty awesome as it sounds amazing full bore or backed off. Big thanks to cajone5 as I don't have time to build much these days and your build inspired me to take on this fun project! Sorry for the big ass pics!

[matmosphere]

Very nice, great placement on the stomp.

Technical question. How did you etch with the bent surface? Did you do the bend on the face after etching?

[glops]

Very nice, great placement on the stomp.

Technical question. How did you etch with the bent surface? Did you do the bend on the face after etching?

Thanks. Got the enclosures from this link:

http://www.ebay.com/itm/60s-Reissue-Pedal-Enclosure-Fuzz-Project-Box-Made-in-USA-RI-Folded-Steel-/320781926498?nma=true&si=0bPdzI%252F0mE%252BJf%252Bf8PhlySemQpmA%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

So, enclosure is already bent. Just need to carefully align the transfer for ironing. Since it's bent, I simply lifted the tub at an angle when etching the footswitch part that's sloped.

[storyboardist]

That looks awesome! Well done

[jubal81]

Now that is epic - oozing with throwback mojo. Love it.

[glops]

Thanks very much! It sounds great, too. Another cool thing is building this is that I found that different transistors have quite an effect on the sound. Seems to be more so than other old fuzzes I have built. Mainly because I have a nice stock pile of PNP germs that I scored from an estate sale years ago that have been collecting dust but 90% of them sound great in this one.

[cajone5]

Totally awesome build!  This puts my meager work to shame Really love the etch!  I am still digging the circuit and have plans to build a mojo one soon too (you've inspired me!)

[davent]

Those big ass pictures are terrific! Beautifully done pedal!

dave

[matmosphere]

Damn, this thing is just too cool looking.

Thanks very much! It sounds great, too. Another cool thing is building this is that I found that different transistors have quite an effect on the sound. Seems to be more so than other old fuzzes I have built. Mainly because I have a nice stock pile of PNP germs that I scored from an estate sale years ago that have been collecting dust but 90% of them sound great in this one.

What did you end up with for transistors?

[Bret608]

This is awesome as always! I remember you building the Albini version back around the time I did, which was when I first starting building actually. I ended up doing a "stock" specs one later as well. It is more what I thought the Perc would sound like, even though I still like that weird dark overdrive sound of the Albini a lot.

[glops]

This puts my meager work to shame Really love the etch!  I am still digging the circuit and have plans to build a mojo one soon too (you've inspired me!)

No way! I really do thank you for your post. It's my favorite fuzz as it's pretty gnarly and even when I turn down the harmonics/input control you get fantastic sounds. I want to build another that switches between 2 harmonics controls now via another footswitch...

[glops]

Those big ass pictures are terrific! Beautifully done pedal!

dave

Thank you, sir!

Damn, this thing is just too cool looking.

What did you end up with for transistors?

And thank you! Right now I have a metal can 2N222 and a 2N2188. I've gather a little collection of oddball Germanium PNPs from estate sales over the years so have the 2N2188 in right now. the 2n404 that I bought from small bear for this sounds good but the 2N2188 sounds  a touch better. But pretty much all of the PNP oddballs that measure 50 hfe to 180 or so sound good in the circuit. I imagine they are all quite leaky but don't have a way to measure leakage. The red transistor sockets were scored recently from an estate sale are of nice quality so I've just been playing with different transistors. The 2N222 sounded the best out of a bunch of other options or I think. After awhile it just gets hard to tell....

This is awesome as always! I remember you building the Albini version back around the time I did, which was when I first starting building actually. I ended up doing a "stock" specs one later as well. It is more what I thought the Perc would sound like, even though I still like that weird dark overdrive sound of the Albini a lot.

Thanks, Brett. I believe yours had the songs about f**king gal etched on it, yes? Yea the Albini one sounded cool, darkish overdrive and had that particular undertone but really do love the stock/Giblet version much better. I still have it on breadboard too going to keep fiddling. Fun to discover a new fuzz to become obsessed with!

[jubal81]

Keep coming back to this thread. Something about this one has me mezmerized.

How's the performance after a buffer? Thought I'd read it likes the high impedance guitar signal like a Fuzz Face.

[playpunk]

Oh my goodness - how did I miss this?

Fantastic build, oozing mojo as usual.

[glops]

Keep coming back to this thread. Something about this one has me mezmerized.

How's the performance after a buffer? Thought I'd read it likes the high impedance guitar signal like a Fuzz Face.

haven't tried after a buffered pedal, been playing it by its lonesome but have hear the same...

Oh my goodness - how did I miss this?

Fantastic build, oozing mojo as usual.

Thanks!