Alright. Here's v4 with your suggestions, Chuck. I did have a good 25 min after dinner to play around with it and I do like the 1st gain stage structure now. It's also still interactive with my guitar. Dial both knobs back and it's pretty much a dirty boost. Then it goes into OD territory, then fuzz.
As mentioned in a previous post, the tone block makes this circuit a bit on the darker side when compared to the ice pick BMP when dimed. When dimed in my circuit it ends up being just right for my taste. I'll try to see if I can get a quick demo tomorrow via my phone.
I do like this one. Oh, and removing C4 in the previous schematic didn't change a thing. Just one less part. You think we can call it? I'll still use it in my practice session tomorrow to confirm with my own ears.
I want to make sure Sandy didn't change the order since Tuesday. If pin 3 is indeed still on the bottom, then the TONE pot is wired backwards. When Sandy says "When dimed in my circuit it ends up being just right for my taste." It tells me that some filtering of the distortion stage is in order.
What do you think?
No, I'm saying that turned up to 10 is the brightest setting and a bit too dark CCW past, say, 9 o'clock. Around noon and it sounds like my neck pickup
I would say so, yes. I mean, could I make fully CW brighter? Yes, but then it becomes too piercing. Super dark settings might be useful to some people.
@Sturdag Lagernathy was super cool and designed a PCB for my Nebula Drive. Super cool dude, btw. The board has been verified and I have 2 more leftover including a faceplate. First come, first served. DM if interested.
It's been quite a while since I've breadboarded something. Now that most of us are approaching the holiday season and colder months, life is slowly quieting down (yardwork, house projects, etc.) and I'm forcing myself to take time here and there to work on some circuits. Here is the PPCB Awful Waffle, or the Crowther Hotcake.
I was intrigued by this circuit for a few reasons. First, there have been a lot of good things said about this circuit on this forum. Secondly, it's low parts count (less troubleshooting possibilities). Third, this is a dirt circuit and ALL the clipping is from the opamp (no diodes) and I don't think I've really heard an opamp clipping circuit before. Lastly, I thought it was interesting to see the presence control as part of the feedback loop.
I built it stock just to see what all the fuss is about. How is it? Honestly, not my favorite dirt circuit. I think this sounds best as a low/medium gain drive pedal that should be stacked with other dirt pedals or an already dirty amp (that's how I played through it this morning for an hour). The DRIVE control sounds best at 2 o'clock and below. Any higher and we're in fuzz territory with too much clipping. I've tried really hard to like fuzz pedals, but they don't suit my playing style. The PRESENCE control gives this circuit some sparkle when dialed back on the drive. The higher the DRIVE setting, the less of an effect the PRESENCE control has IMO.
Is this a bad pedal? Absolutely not! I definitely see the appeal of it and I may throw a second one on there in series (I guess I could call it the Short Stack). There is definitely a place for this circuit on someone's pedalboard. Just not mine. It was fun dusting off my protoboard for an afternoon, though.
The cap is small enough that the opamp (even a shitty little 741) will fight it and win. Sticking a cap from the output of an opamp to ground is usually a bad idea because it either does nothing, or makes the opamp oscillate.
The only exception is OTAs because their output impedance is very high.
So, that would probably explain my findings in only swapping out opamps in keeping the circuit stock. I had a OP07, TL061, and TL071.
OP07 caused a lot of glitchy, octave-y oscillation once the DRIVE control was cranked above 10 o'clock. Reminded me of a MXR Blue Box with more noise. Fun, but not really musical.
TL061 sounded brittle and still had some oscillation once cranked.
TL071 had some glitchiness, but no oscillation. I'm guessing there was a reason for using a 741 in here. I may try swapping opamps out again when I have a few minutes, but removing C4 this time.
