PWM (Tim Escobedo Synth Fuzz)

[Aleph Null]

I got this PCB in a trade with Mitchell over at Super Freq. This is his implementation of Tim Escobedo's "PWM". It includes the optional LFO. It's a square wave synth with modulated pulse width. In a track it could be mistaken for an old analog synth.



I tried a spray-can finish for the first time in a long time. Historically, I've had a hard time getting the paint to adhere. I'm optimistic that the few tricks I've learned over the years will help. Aesthetically, I wanted it to look like a Lisa Frank fever dream about fuzz.



You could fit all the components in a 1590A. The extra room is for all the attitude.



Of course, I can't leave well enough alone, so I made some mods.

• I swapped lugs 1 and 3 of the Rate control so that clockwise was faster.
• I jumpered the LFO switch and opted to put a big-ass 10mm bypass LED in its place. Setting Depth to zero still kills the modulation.
• I changed C2 to 6.8nF and added a 47k resistor between lug 3 of the PWM (labeled "Width" on my build) and ground. Without the minimum resistance, it's possible to set the pulse width so narrow that the signal cuts out entirely.
• I changed C2 to 10uF and R2 to 4.7k. This widens the range of the LFO.

All and all this is a fun circuit and unlike anything else I've built!

[NorthCoast]

Nice! That's a really cool circuit.

I've always liked small boards in large enclosures.

How do you like the sound with the LFO going?



btw, when you first posted this, I don't think it showed up in my 'Unread Posts'?? Just thought I'd mention it, I don't know if others have had that happen.

[Aleph Null]

How do you like the sound with the LFO going?

At first I thought a slow setting would sound good over heavy riffing, something akin to EVH with a phaser, but something about the modulation tends to obscure the rhythm. Medium to fast sounds good on single note lead lines. Sounds like a synth part!