Found Myself a Zonk Machine
Posted: Thu Nov 12, 2020 4:21 pm
At the behest of a few members, I decided to give this Zonk its own thread. Hope that isn't weird.
Thought I'd throw some pics of my Zonk up. I think it's an early one on PCB. It came to me without a battery panel and with an unmarked gold button replacement Q3. It sounded very good, but was pretty dark, lower gain, and didn't gate at all.
I decided to build a new battery trap, and, while I was in there, figured I might as well swap Q3 to something more correct. I measured the little gold device when I had it out, and it measured 12 hFe with no leak
Though it's not really like the old ones I've heard, I really like a Zonk with some gating: it gives more texture and swirl to the character. I tack soldered some sockets and started rolling transistors. Started with a load of unbranded and Mullard-branded OC71, but all of them passed along some crud in the signal generated by Q1 probably. I then moved on to OC44, and found the same thing. I was starting to realize why the repairman of old went with such a low-gain device.
I persisted and eventually found a great Q3 in a super high hFe, high leak Mullard-branded OC44 w/ the cool Roman font. After surgery it gained a bit more high-end, sustain, and a touch of gating. Lots of scratch and stutter with the OC44, and silent at idle.
One interesting quirk of this Zonk is that, no matter what went in Q3, it maintained a subtle bloom, not unlike the Supa MKI, that lended an explosive quality. It's also quite dark. Pretty cool effects that give this one a distinct personality.
Screenshot_20201104-175846~2 by Matthew Seppi, on Flickr
Screenshot_20201104-175820~2 by Matthew Seppi, on Flickr
2020-11-04_10-26-37 by Matthew Seppi, on Flickr
IMG_20201027_185348230~2 by Matthew Seppi, on Flickr
IMG_20201027_194134_254 by Matthew Seppi, on Flickr
IMG_20201027_183633388~3 by Matthew Seppi, on Flickr
Thought I'd throw some pics of my Zonk up. I think it's an early one on PCB. It came to me without a battery panel and with an unmarked gold button replacement Q3. It sounded very good, but was pretty dark, lower gain, and didn't gate at all.
I decided to build a new battery trap, and, while I was in there, figured I might as well swap Q3 to something more correct. I measured the little gold device when I had it out, and it measured 12 hFe with no leak
Though it's not really like the old ones I've heard, I really like a Zonk with some gating: it gives more texture and swirl to the character. I tack soldered some sockets and started rolling transistors. Started with a load of unbranded and Mullard-branded OC71, but all of them passed along some crud in the signal generated by Q1 probably. I then moved on to OC44, and found the same thing. I was starting to realize why the repairman of old went with such a low-gain device.
I persisted and eventually found a great Q3 in a super high hFe, high leak Mullard-branded OC44 w/ the cool Roman font. After surgery it gained a bit more high-end, sustain, and a touch of gating. Lots of scratch and stutter with the OC44, and silent at idle.
One interesting quirk of this Zonk is that, no matter what went in Q3, it maintained a subtle bloom, not unlike the Supa MKI, that lended an explosive quality. It's also quite dark. Pretty cool effects that give this one a distinct personality.
Screenshot_20201104-175846~2 by Matthew Seppi, on Flickr
Screenshot_20201104-175820~2 by Matthew Seppi, on Flickr
2020-11-04_10-26-37 by Matthew Seppi, on Flickr
IMG_20201027_185348230~2 by Matthew Seppi, on Flickr
IMG_20201027_194134_254 by Matthew Seppi, on Flickr
IMG_20201027_183633388~3 by Matthew Seppi, on Flickr