Pulse Wave Unit

I’m still catching up on the various discussions, and I’m sure that this has been brought up before, but I didn’t see it listed in the requests on this forum. Are there plans to add a square/pulse wave oscillator? I’m asking because I’m trying to build a particular kind of filter where I use a tuned pulse to drive a VCA. I’ll post something once I sort it out - I figure I can achieve a similar effect using some combination of modules. I just find a pulse wave to be really convenient as a modulation source, in addition to liking the way it sounds as an oscillator.

Try using a sine oscillator followed by a limiter where the pre-gain is a high positive value. That’ll give you a square wave

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I too would really like a square wave oscillator with variable PWM between 0 and 100%
Please Brain!! :slight_smile:
I’m sure this would be a trivial one to write…

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I believe it’s the tap tempo unit that has a pulse width control. I haven’t tried it at audio rate and I’m not in the studio now to give it a shot. Wonder if that would work as a makeshift oscillator?

using to saws at the same frequency of which one is inverted also works… different context, but outlined here: Oscillator phases

Thanks, all! I tried using Tap Tempo, but that doesn’t reach the frequencies I need, nor does it allow an external VC in to control the frequency that I could tell. So used vcoadsr’s suggestion of the sine wave followed by the limiter, and that seemed to work well enough. Having pulse width control would be nice, though.

Just to explain what I was trying to do, I made a simple filter of sorts using a VCA driven by a square wave tuned to a harmonic of the frequency of the note being played. The VCA effectively cuts notches out of the source sound. I started fooling with the idea some time ago when I was trying to achieve a Hoover sound in modular. Never quite go there, but along the way came across this interesting (to me, at least) effect.

In case anyone wants to play along at home, here’s the chain file: http://pupation.com/music/VCA%20based%20filter1.lua
And an example: http://pupation.com/music/vca_filter_example1.wav - It’s a simple loop from my Hertz Donut running through the filter. The 1st 2 cycles are with the bypass on, the last few are with the filter engaged.

It’s admittedly a very basic idea, but I just wanted to explain why I wanted the pulse wave in the first place.

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