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Demultiplexer approach

Looking for sanity check on a patch in the pencil-and-paper stage.

It’s a multi-channel looper patch which will use several footswitches to control several synchronized looper units. My footswitches are MIDI, and my MIDI-to-CV channels are limited so I am trying to multiplex several switch controls onto a single CV stream, then demultiplex them in the patch into several trigger/gates. A little Rube Goldberg but it’s what I have to work with.

So I can encode 4 gate streams into 1 CV as: (G1 + 2G2 + 4G3 + 8*G4) (scaled to the full MIDI CC range), using some software magic. Then through MIDI->CV, and into the ER-301 I get a single CV that I want to decode into 4 separate bits.

The approach I am thinking of is to have 4 sample players, each in a global chain, with samples preloaded that are the same length, square waves of frequency 1, 2, 4, and 8, having 16 equally spaced slices in each sample. The frequency 1 has 1 cycle of square wave, frequency 2 has 2 cycles, and so on. Then I send the same input CV to all 4 global chains to select the slice. The output from each sample player should be a constant value corresponding to one of the bits, which I can then use as a gate signal to control the looper components in the patch.

Does that make sense? Is there another way besides global chains to split a single signal input into multiple outputs?

You can park an audio or CV process inside a linear fader control in a custom unit and then reference that anywhere inside the custom unit where you can assign an input.

@NeilParfitt’s getting started video #28 part 1, I think is the one that illustrates it.

Have you looked at this thread around creating a sequential switch? I don’t think this is exactly equivalent to what you’re trying to do, but there are definitely some parallels.

I’d be really interested to see if you can get this working!

Great tip, I saw that video but I didn’t really pick up that part. I’ll be back at the ER-301 Monday night, I’ll be sure to follow up.