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paulovski
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Joined: 09/19/2012 - 06:13
Analog Shift Register

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What's that then? It's a cross between a Sample and Hold unit and a Delay. They have multi steps, a little bit like an analog sequencer, and are commonly used to process 'Note CV'. With one (or more) oscillator per step. Two steps are useful. Three start to get interesting. I've managed to get three steps out of one Modsynth (A), and four out of a combination of two (B).

If you press 'play', you'll hear this, rhythmically disjointed, pattern. And, as you'd expect, the first trigger has the lowest pitch. If you scroll up to machine 'A', you'll see a 3>1 mixer, in the top row, with input 1 turned up. This is the first step. Turn that down, and turn up input 2 (step 2). You'll hear the same pitches. But, if you look at the pattern, you'll see (and hear) that the lowest pitch is now on the second trigger. Note CV has shifted along by one trigger. If you turn down input 2, and turn up input 3, (step 3. See where we're going here?) then you'll hear that lowest pitch shifted along to the third trigger.
If you mix all three inputs, the result is a cascading, kind of, 'song in the round' effect.

This is not the prettiest of patterns. A similar effect can be set up by, just, running 'Note CV' through a series of delays. But the notes would have to be evenly spaced and correspond with delay times. With ASRs, that's optional. You trigger them (within reason) when you want to. So, if you move those notes around in the time line, it won't stop working.
If you delete one of those notes, then the number of different pitches will correspond to the number of steps, and the whole thing will settle down to play a triad in a pseudo polyphonic kind of way.

And that's about it. In 'A', I'm using three Waveform Generators with identical settings. Feel free to change any of that. I insist.

In setup 'B', the first step is in 'B1' (the WG on the right) and there are three more steps in 'B2'. The output of B2 is fed into B1 for filtering and Volume envelope.
Mod fans may well spot the employment of the Modsynth's, built in, DC signal generator.

Have fun.

James
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Joined: 01/21/2013 - 07:09
Every day is a school day 

Every day is a school day laugh

JHSound
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Joined: 06/04/2015 - 11:21
Step 1 for the slow of mind .

Step 1 for the slow of mind ... I thought a WG had to be modified by an envelope directly but you set it up so that the envelope modifies the cutoff/resonance of a filter processing the signal from the WG and that accomplishes the same thing ?? I just proved it does with a simplified setup in a new modular, but I am not sure why it works.  Sorry if this question shows how far I have yet to go in understanding how signals are processed.

nitro27
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Joined: 10/11/2015 - 18:27
Dang that's cool. Oh yeah,

Dang that's cool. Oh yeah, protip, if you need a Very Short Delay, just enough to make sure it doesn't all get computer at once, you can place modules in reverse order - right to left, bottom to top. That way when a module's output gets updated, it doesn't get sent to the next input until the next "frame". I got 4 pitches in there.

Also I'm like 80% sure I can use this to make a KSSynth and I just don't. know. how.

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paulovski
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Joined: 09/19/2012 - 06:13
@JHS. The DADSR is

@JHS. The DADSR is controlling the filter and nothing else. In the same way that the Subsynth filter envelope just controls the filter. Here, it's controlling resonance as well, because why not.
The decay envelope is just a little burst to trigger the gates of the SH units.
The AR envelope, top right, is the volume envelope. This particular setup only needs one, overall volume envelope at any one time. I could run three cables into three different amplifiers in three oscillators and get them all to do, exactly, the same thing as each other, and clutter everything up with cables. Or I could, just, use the, one, overall volume amplifier (the volume mod input).
There are good reasons to go direct to the oscillators, sometimes. That volume mod input can be a bit clicky. Sounds with higher frequency content, like this, don't really show that, but deep basses do. And direct can be (is) a bit tighter, so I'd recommend doing that for percussion synthesis.
Have a look at B2, and it's output meter. There's no volume envelope in that synth. The output is, just, going to run up against another overall volume envelope in B1. There's no point giving it two. And I'd rather use that precious rack space for something else.

@Nitro I haven't had a chance to listen, and I could be wrong. But I don't think reversing the order is going to make a lot of difference here. The CV value that needs to go into each SH unit should already be there at it's input, waiting to be sampled, before it gets triggered.
Four steps in one is good for the sake of not much, meaningful, filter modulation. And I wasn't having that.
80% sure, probably, translates as yes. But, that KS is your baby :)

Edit. Sorry Nitro. I hadn't had a chance to look at what you'd done there. Bang on!

paulovski
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Joined: 09/19/2012 - 06:13
So that makes seven steps

So that makes seven steps doable. Nice one.

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paulovski
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Joined: 09/19/2012 - 06:13
I think eight will do me.

I think eight will do me. More are feasabe.

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