I've built this and everything seems to be working although the feedback part doesn't sound quite right. Instead of crazy fuzzy type of oscillating, I'm getting more high pitch squeals. I've tried a handful of jfets including k30s all with similar results.
I had the same results with the feedback knob. I actually found that it really made no noticeable change to the circuit if I removed it. So that's what I did. This is a really great sounding analog ringer-style octave fuzz even with out it. I also looked over the feedback section of DeadEnd's schematic and this drawing looks to be dead on accurate. And with a lack of comprehensive demos on youtube, I don't know if we are going to get any closer without an original Octavella to compare to. Either way - I don't like building stuff and not using it so I want to see if I can verify the Gommorah and put these two in parallel for 3 really awful octaves of fuzz!
In my build feedback dial definitely works, turn it up and it goes into juicy self-oscillation. Could be fun to patch it to expression pedal. I used 2sk30 as in original, though I had to twist its legs as pinout is different. Tried out different jfets in place, J113 or J112 didn't seem to have enough beef, there was much less fuzz and feedback didn't work, J201 worked but seemed to push it too much. It's worth to socket diodes, some germaniums give interesting results there. In the end I wouldn't say, it sounds good, I actually think it sounds terrible. Unless you're in the mood for some high pitched ear-splitting noises, it which case it sounds great. I think it could be tagged as verified. Side note if you use socket for IC, better move the 22n cap from above the IC to the edge of the board, as it gets in the way when you want to pull the IC out.
I've built this and everything seems to be working although the feedback part doesn't sound quite right. Instead of crazy fuzzy type of oscillating, I'm getting more high pitch squeals. I've tried a handful of jfets including k30s all with similar results.
ReplyDeleteI had the same results with the feedback knob. I actually found that it really made no noticeable change to the circuit if I removed it. So that's what I did. This is a really great sounding analog ringer-style octave fuzz even with out it. I also looked over the feedback section of DeadEnd's schematic and this drawing looks to be dead on accurate. And with a lack of comprehensive demos on youtube, I don't know if we are going to get any closer without an original Octavella to compare to. Either way - I don't like building stuff and not using it so I want to see if I can verify the Gommorah and put these two in parallel for 3 really awful octaves of fuzz!
ReplyDeleteIn my build feedback dial definitely works, turn it up and it goes into juicy self-oscillation. Could be fun to patch it to expression pedal. I used 2sk30 as in original, though I had to twist its legs as pinout is different. Tried out different jfets in place, J113 or J112 didn't seem to have enough beef, there was much less fuzz and feedback didn't work, J201 worked but seemed to push it too much. It's worth to socket diodes, some germaniums give interesting results there.
ReplyDeleteIn the end I wouldn't say, it sounds good, I actually think it sounds terrible. Unless you're in the mood for some high pitched ear-splitting noises, it which case it sounds great. I think it could be tagged as verified.
Side note if you use socket for IC, better move the 22n cap from above the IC to the edge of the board, as it gets in the way when you want to pull the IC out.