Darth Punk - modified Distortion + for bass.

[Willybomb]

Gudday all.

Here's Darth Punk, a modified Distortion+ with a clean blend as it will be a bass drive for a friend's son.
- Mods:  LED pair in the opamp feedback loop, pair of Bat46 clipping to ground.  The blend is a pcb I got from someone here.

This was going to be a X-fuzz, but it was a bit noisier than I liked, but I'd already drilled and finished the box so I needed a 2 knob drive I could use with a blend.  I'd heard the Dist+ was pretty good with LEDs, but I wasn't impressed with them going to ground so I tried them in the loop.... and holy hell does it sound good with them there.  From there it was a case of trying different diodes to ground.  I tried bat46, 1n4148, 1n270 and the LEDs, and decided to settle on the bat46, although they all sounded pretty good. 1n4148s sucked too much signal out iirc and I couldn't get unity.

It's not often I build something and decide that I'll do another, but I'm going to build one of these for my next bass multi.

I had an issue with the first split/blend board on vero in that it seemed to suck something out of the signal, so I tried a pcb I got on these forums a year or two ago and it worked really well until I did something trimming leads and I didn't get any clean signal in the blend.  I swapped the pcb out for another and it works great.  This is a really cool sounding bass drive.

I did the graphics in photoshop, adding the spikes to Darth's head. 

The guts are a bit messy, but hey, it's half vero and two circuits.

[EBK]

I couldn't help but think of this guy when I read the thread title:

[mjg]

That's cool.  I love the graphics.   

I'll have to breadboard this and try it out on bass. 

[jubal81]

Super build! The clipping arrangement sounds very nice. Bet it's a growly beast.

[Willybomb]

Jubal, I could not believe how good it sounded the first time I put the LEDs in the opamp loop, changing the hard clippers gives it a bit more, and the blend just does it's job.  I was after something nasty but not fizzy, and this really fits the bill.

I really should do a demo.

[Leevibe]

I love that graphic. Nice work!

[dawson]

Neat- all dads could use a friend like you!

I'm going to attempt a DOD 250 in the near future, which is a very similar circuit to the Distortion + and I'm intrigued by your positive results when moving the LED's around, but things like clipping are still like sorcery to me.

So from reading your report and the comments, am I to understand that your LED's start in the same place as the BAT46 and end on a pin of the IC?

Thanks for sharing!

P.S. Cool technique putting your printout right on top of the vero- very wise indeed.

[Willybomb]

My Bat46 replace the germs that go to ground normally.  The back to back LEDs are across pins 1 and 3 of the gain pot, similar to Wampler's Dist+ mods (although he uses different diodes there).

The printout glued to vero thing I learnt back in 86 when I did my first layout for a c-64 controlled robot from the Usborne book "How to make computer controlled robots".  I never finished the robot, but that book says to do that.  I remembered it a year or so ago after not doing it for years, and it's cut the number of failed veros to about 1 in 10, usually because there's a cut under a component that isn't clearly on the layout.

[dawson]

My Bat46 replace the germs that go to ground normally.  The back to back LEDs are across pins 1 and 3 of the gain pot, similar to Wampler's Dist+ mods (although he uses different diodes there).

Great, I'll be experimenting, thank you!

P.S. It's never too late to finish learning how to build robots.