Jolt fuzz (a minor unpleasant surprise)

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Nocentelli
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Post by Nocentelli »

I really enjoyed messing about with Fairfield's unpleasant surprise circuit on the breadboard (or at least the schematic called the "calamity fuzz" that bugg has over at his pcb site), so I made a clone. If you haven't come across it before, it's a heavily gated and compressed aggro-fuzz, with three mode switches. It does some truly deranged sounds, some useful dark/doomy/sludge/stoner metal chug, but it's also capable of some very interesting textural stuff when you play with the onset control at the gating point, especially with a dense synthy/droning sound source. It was a great pedal but it stopped working properly after a while. I couldn't face debugging it and decided instead to rework it a bit when making a new one since I didn't really use some of the options on the switches (and I hate switches) and i wanted a few more controls to tweak whilst using looped or synthy stuf.
Jolt fuzz nocentelli.png
I've removed the chaos mode entirely, changed the treble switch into a roll-off pot, and put in a "texture" pot in lieu of the "gain mode" switch. This works pretty nicely to soften the abrupt attack of the stock sound when rolled back, but I lowered the resistance to ground at the end of the pot (minimum resistance of 47k is somewhat lower than the 68k || 270k = 54k in "non-g" mode), and it now seems to have an even more aggressive or abrupt attack than the original when set at maximum.

I'm currently building the new circuit on vero: I also got fixated on the idea of using one of the SIP NJM4558s chips I bought years ago and have never managed to use. I had the idea I could do a much more compact layout with the single strip opamp and no switches, but it was actually as much of a pain as doing the layout for a regular dip-8, maybe more so, and it is still 28x10. I'll post the layout if/when it's working. I also have no idea if the 4558 sounds any different to the TL072, but it does sound pretty good.
modman wrote: Let's hope it's not a hit, because soldering up the same pedal everyday, is a sad life. It's that same ole devilish double bind again...

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