Yes, I'm sure a 7660S or MAX1044 will work as drop in replacement. But you might want to reduce the 100uF cap (at the bottom left corner) to 10uF since that is what 7660S/MAX1044 datasheets suggests.
Cool, thanks. Just built it and I'm getting nothing but a stuttering sound that speeds up and slows down when gain is adjusted. New one for me, but I'll double check everything later just in case I've messed up somewhere.
Hey, I built it and it works. Pretty cool fat distortion. Used a B10K for treble and on the Savage pot I had some squealing after 90%, so I soldered a 1k resistor before lugs 1+2 and I got rid of it. This savage control is cool as it brings in some wah voicing which frequency you can adjust to your liking... also used 1n4001 as suggested. Cheers!
Built this. Got a couple things going on. First off it sounds more like a distortion than an overdrive to me (at least my build, dirtier than the demo . The gain pot maxed I get an awful squeal, last above around the 7th fret on the high e it sounds like the highs are getting filtered out about the 12th they sound completely filtered. I did do a series thing for the 390pf as I only had 330 and 470 so I may try swapping that for either of those values, anyways will need to do some more tinkering.
Tinkering around with it some more I seem to have everything figured out othern than the gain pot feedback at when maxed. Wondering if boxing will fix. It doesn’t lack in volume that’s for sure.
Have you tried putting a buffer up front? I built a Dunwich HM-2 last week that squeals uncontrollably unless it has a buffer up front - could be an impedence issue.
I was full on prepared to take the pots off this thing ms add it to my pile of just didn’t love it circuits. Watched a couple more demos and realized I had my settings all wrong (which I always have a hard time with settings before boxing). Put some knobs on the pots and messed around some more and I’m now going to box this up. Now do I dare try to fit this in a 125b, it’s going to be close.
I originally out 1n4001’s in for the diodes. I ended up trying some 34a’s and no feedback, tried 4148’s no feedback. Tried 4001’s again feedback. So mine now has 4148’s in it. But I’m getting squeal now wirb the savage pot maxed and at max gain, so I guess I’ll do the 1k there as mentioned above.
Well I don’t know if it’s the end of the world for me as I probably won’t run it at max gain. I’m not convinced it mine is right as I would describe it as kind of fizzy sounding but I’ve noticed depending on pot settings it can vary a lot.
What is doing the 100n cap between 5 and 8 Pins of the 7662? In the schematic there is a 100uf and 100n paralelled to filter the -V.... It looks like the 100uf is missing. The 2m2 resistor at the the input is in the schematic?? I dont see it
So after messing with this thing on and off for a couple months now I finally just bought the pcb. My build was spot on to the layout never did get rid of the feedback when savage and gain pot were maxed and it just didn’t quite sound right to me. Bought the pcb the schematic was taken from and there’s no feedback when the savage pot is maxed (which I apparently wasn’t the only person having this problem) and it overall sounds better. I kind of suspect the offboard wiring being part of the issue maybe shielded wiring would help with it but I’d recommend just getting the pcb and save yourself the headache if you want this one.
Thanks! I also found that the 100n cap at pin 5 of the IC3 should be grounded so can be moved just one row up and it seems that the 100uf parallel cap(c103) is missing.
Hello, I have some squealing at 95% of the Gain control and a weird farty decay at any gain level. All controls works but something is wrong. I've tried a lots of oamps and diodes and it didn't fix the problem.
Newbie question, the 1uf cap and 1k5 res (C12 & R11) at the bottom before the clipping diodes in the schematic are swapped, does the order matter here?
Could I use a TC7660 in place of the 7662BC?
ReplyDeleteYes, I'm sure a 7660S or MAX1044 will work as drop in replacement. But you might want to reduce the 100uF cap (at the bottom left corner) to 10uF since that is what 7660S/MAX1044 datasheets suggests.
DeleteCool, thanks. Just built it and I'm getting nothing but a stuttering sound that speeds up and slows down when gain is adjusted. New one for me, but I'll double check everything later just in case I've messed up somewhere.
DeleteCouldn't find the problem so I just made it again. Works fine. I used to have this pedal and it sounds pretty much as I remember.
Deletethe datasheet of the 7660s show a case when 100uf caps are needed, the external components of the 7660 and 7662 are the same
DeleteHey, I built it and it works. Pretty cool fat distortion.
ReplyDeleteUsed a B10K for treble and on the Savage pot I had some squealing after 90%, so I soldered a 1k resistor before lugs 1+2 and I got rid of it. This savage control is cool as it brings in some wah voicing which frequency you can adjust to your liking... also used 1n4001 as suggested. Cheers!
This comment has been removed by the author.
ReplyDeleteThanks for verifying!
ReplyDeleteTagged.
This comment has been removed by the author.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteBuilt this. Got a couple things going on. First off it sounds more like a distortion than an overdrive to me (at least my build, dirtier than the demo . The gain pot maxed I get an awful squeal, last above around the 7th fret on the high e it sounds like the highs are getting filtered out about the 12th they sound completely filtered. I did do a series thing for the 390pf as I only had 330 and 470 so I may try swapping that for either of those values, anyways will need to do some more tinkering.
ReplyDeleteTinkering around with it some more I seem to have everything figured out othern than the gain pot feedback at when maxed. Wondering if boxing will fix. It doesn’t lack in volume that’s for sure.
ReplyDeleteI still had the feedback on the gain pot after boxing. Can't quite figure out why.
DeleteHave you tried putting a buffer up front? I built a Dunwich HM-2 last week that squeals uncontrollably unless it has a buffer up front - could be an impedence issue.
DeleteI was full on prepared to take the pots off this thing ms add it to my pile of just didn’t love it circuits. Watched a couple more demos and realized I had my settings all wrong (which I always have a hard time with settings before boxing). Put some knobs on the pots and messed around some more and I’m now going to box this up. Now do I dare try to fit this in a 125b, it’s going to be close.
DeleteI originally out 1n4001’s in for the diodes. I ended up trying some 34a’s and no feedback, tried 4148’s no feedback. Tried 4001’s again feedback. So mine now has 4148’s in it. But I’m getting squeal now wirb the savage pot maxed and at max gain, so I guess I’ll do the 1k there as mentioned above.
DeleteWell I don’t know if it’s the end of the world for me as I probably won’t run it at max gain. I’m not convinced it mine is right as I would describe it as kind of fizzy sounding but I’ve noticed depending on pot settings it can vary a lot.
ReplyDeleteWhat is doing the 100n cap between 5 and 8 Pins of the 7662? In the schematic there is a 100uf and 100n paralelled to filter the -V.... It looks like the 100uf is missing.
ReplyDeleteThe 2m2 resistor at the the input is in the schematic?? I dont see it
So after messing with this thing on and off for a couple months now I finally just bought the pcb. My build was spot on to the layout never did get rid of the feedback when savage and gain pot were maxed and it just didn’t quite sound right to me. Bought the pcb the schematic was taken from and there’s no feedback when the savage pot is maxed (which I apparently wasn’t the only person having this problem) and it overall sounds better. I kind of suspect the offboard wiring being part of the issue maybe shielded wiring would help with it but I’d recommend just getting the pcb and save yourself the headache if you want this one.
ReplyDelete122k(r3) resistor is 22k.
ReplyDeleteFixed.
DeleteThanks! I also found that the 100n cap at pin 5 of the IC3 should be grounded so can be moved just one row up and it seems that the 100uf parallel cap(c103) is missing.
Delete100nF cap fixed. Do you mean C102 for the 100uF cap?. It is located left to IC2. It is connected across Ground and -9v.
DeleteCool! and yes I was referring to the c102 cap.
DeleteHello, I have some squealing at 95% of the Gain control and a weird farty decay at any gain level. All controls works but something is wrong. I've tried a lots of oamps and diodes and it didn't fix the problem.
ReplyDeleteVoltages:
IC 1
1. 0
2. 0
3. 0
4. -8.51
5. 0
6. 0
7. 0
8. 8.73
IC 2
1. 0
2. 0
3. 0
4. -8.52
5. 0
6. 0
7. 0
8. 8.73
IC 3: 1044
1. 8.74
2. 4.33
3. 0
4. -4.28
5. -8.52
6. 4.14
7. 6.43
8. 8.73
I reduced the 100uF cap at the bottom left corner to 10uF as fuzzhead suggest.
Newbie question, the 1uf cap and 1k5 res (C12 & R11) at the bottom before the clipping diodes in the schematic are swapped, does the order matter here?
DeleteNo, the order doesn't matter.
DeleteOh, and your voltages looks fine. You might need to double check, your values, solder bridges and joints...
DeleteThanks fuzzhead, I checked several times but I can't find the problem, did you build this layout?
DeleteNo, I have not... It is in the que but sadly there is not much time for building stuff these days.
Delete