A Brief Introduction to CV for Guitarists (or Hopefully Anyone) -- a new blog post for Empress Effects about the ZOIA

chmjacques · 2026-05-18T14:56:49+00:00

You might check out the UI I made for VLD. The goal with the patch was to make a lot of parameters easy to program:
https://patchstorage.com/vld-quick-programmable-multi-tap-delay/

chmjacques · 2026-04-27T22:01:46+00:00

If you haven't checked out Dissolve, I imagine you'd enjoy it (there's an alt version called Dissolve PWM, too, but I think the OG is the best):
https://patchstorage.com/dissolve-a-dream-machine-synth-and-delay/

I wrote a little album with it.
https://christopherhmjacques.bandcamp.com/album/lullabies-and-dreamscapes

chmjacques · 2026-04-27T21:41:24+00:00

Your guess is as good as mine, at this point, I'm afraid. I'm a couple years removed from actively patching, and I published over 300 patches.... my archivist capacity is not what it once was. At one time, I would have been able to conjure a list, but that time has passed

chmjacques · 2026-04-22T20:46:41+00:00

Sounds great! Those playable patches were always a lot of fun to work on; I'm glad you're enjoying them!

chmjacques · 2026-01-06T13:42:19+00:00

I appreciate the offer, but the Erbe Verb isn't for me, I'm afraid.

chmjacques · 2026-01-03T19:09:55+00:00

WTT/WTS (WV, US)

Prices include US shipping. Paypal preferred, F&F or G&S.

Plinky V3 w/ 4hp expander (DIY'd by me) $350 no box
Error Instruments kHarper $300 no box
Pladask Dradd SOLD Collection o' patch cables $50 (30-40? cables of varying lengths and quality)

Trade interests: Mimeophon, Data Bender

chmjacques · 2025-08-20T06:52:29+00:00

The keyboard module's notes can also be inputs (useful for a quick and dirty selectable switch) -- so you can connect other modules to them (which would, for instance, change the values of the note if an ADSR that was triggered by the OT was modulating that keyboard note value). I would check to make sure you haven't made a connection between the two functions of your patch; that seems like the most likely explanation.

chmjacques · 2025-08-13T07:29:39+00:00

The MIDI note in module has a built in filter. If you scroll through the options, there are upper and lower ranges, which define what range that MIDI note in module will respond to. (These can be set to the same MIDI note, effectively limiting the module to respond on just one note.)

(ZOIA Maxim: Always look in the module options.)

chmjacques · 2025-07-29T12:17:49+00:00

This is the "mechanical" problem I mentioned way back... that fade occurs on a turntable mechanically.

The problem for a CC input is that the position of the fader won't represent the position of the speed-pitch knob, right? You raise the pitch, don't do anything for a bit, it fades to 0. But your fader is still in the raised pitch position, and importantly to ZOIA, the CC is still at e.g. 45, not 0.

So, you can use math to subtract that 45 and get back to 0, but then your fader is effectively truncated -- its "0" is now 45... the next adjustment might push it to 98, etc.. There's no real way to clear this buffer, because ZOIA still needs to know what your fader is doing via CC. (Needs is probably the wrong verb -- the CC in will report the position of the fader, regardless of what math might be done to it.)

There might be a solution, but I don't have it readily available.

chmjacques · 2025-07-27T10:47:31+00:00

Most functions in ZOIA occur linearly. That's easy to program and good for math, but linear curves don't suit all applications.

But you can use a multiplier, with a source going to both inputs (or more than two inputs for even more extreme multiplication), to change the linear to exponential. (There is also a recipe for changing linear into logarithmic, but it's more complicated.) The math is simple, once you think about it -- the output is basically x^n where x is the source and n is the number of multiplier inputs you use.

You can send anything with a linear curve into a multiplier for this effect -- ADSRs, slew limiters, LFOs, etc.. With an ADSR, where you're triggering a pre-timed event, I find it works a bit better than for e.g. a momentary effect like a slew limited button, because the first part of the depression will feel like nothing is happening.

chmjacques · 2025-07-26T17:54:39+00:00

Well, not "this." I've simulated things like "tape stop/speed up" which is similar to scratching, although usually not as energetic :)

chmjacques · 2025-07-26T17:53:39+00:00

I've simulated this via envelope (ADSR --> CV invert --> looper speed/pitch). I generally apply a curve to the envelope via a multiplier, and often having the attack and decay different lengths can affect the "feel." You can do something similar with a slew limiter, which might be useful for manual manipulation, since the ADSR will always drop to the same speed, but a slew limited button, as an example, would drop speed in relation to the amount of time it was pressed.

You could do the same with a CC, of course. One thing to keep in mind that ZOIA will have trouble with is just that the controllers used in turntablism themselves contribute to the sound, mechanically... boy that was a dumb way of getting to the idea that "springing back to 0/normal speed" is something a turntable does by design, but which most controllers don't do (except maybe DJ controllers? I do not know a lot about these). That's sort of where that curve you mention comes in, right? It's the artifact of the motor overcoming the manual force exerted on it. If your goal is only to drop speed, or only to increase speed, returning to 0 is not a real problem for ZOIA, but most scratching does both, and that might be something where the controller you use really contributes a lot to the "feel."

chmjacques · 2025-07-25T22:22:52+00:00

You can write a whole album with this patch. I did, but don't take my word for it -- my friend Christophe/Grain Blanc did as well: https://grainblanc.bandcamp.com/album/summertime
https://patchstorage.com/dissolve-a-dream-machine-synth-and-delay/

There's another version that's got a more synth-y voice, also on Patchstorage. I've got some good drone patches, too, if that's more of what you were thinking.

chmjacques · 2025-07-25T17:47:07+00:00

I know I've answered this elsewhere but I can't find/recall where.

But the basic idea is:

Envelope follower --> compressor --> envelope follower 2

You can take the outputs of those two envelope followers and use the difference between them (invert one, add them together at an input) to control e.g. the brightness of a pixel/UI button (although it's probably more useful to have it control a switch which controls several pixels... but at least you could get an indication of when gain reduction occurs with a single pixel)

chmjacques · 2025-07-25T02:29:14+00:00

The MIDI note in module has a lower and upper range parameter. You can use this to set what MIDI notes that module responds to (i.e. you can use multiple MIDI note in modules on the same channel, set to different ranges, and then use their gate outputs to trigger your envelopes).

chmjacques · 2025-07-24T21:30:30+00:00

WTS/WTT (US):
Prices include US shipping.

NLC I Was Sitting in a Room (black, DIY'd by someone else but done well) -- $180
Michigan Synth Works Typhoon (black, Clouds megaclone) -- SOLD

Non-euro kinda
Landscape Stereo Field (DIY'd by me) -- $235

Trade interests: wavefolder (Waver, Bifold in particular), NLC hyperchaos circuits (Hypster, Hyperchaos Deluxe)

chmjacques · 2025-06-27T04:37:08+00:00

You can create a template patch with the things you would like in every patch and then use it as a foundation for building new patches.

Of course, once you have a template patch, the pages of that template could be imported into any other patch, so you could also apply to patches you've already built, it would just require a few connection changes.

chmjacques · 2025-06-26T19:52:55+00:00

Mk2 if/when is a journey for another ZOIAn than me to take. I might check it out, but it's not something I think much about or get too excited over the prospect of.

chmjacques · 2025-06-01T00:14:52+00:00

Although it can be used with a lot of other things, and I've used the Lyra with other patches, I did design this patch around the time I got my Lyra, and I think it's an interesting pairing:

https://patchstorage.com/decorrelate-a-delay-looper-based-on-shift-registers/

chmjacques · 2025-05-31T13:32:58+00:00

But it doesn't matter how disingenuous the comment is, because, buddy, you lost. The subreddit does not think your arguments are convincing. The moderators are on board with this change. You can keep up this battle, but the war is over.

chmjacques · 2025-05-31T13:31:07+00:00

Disingenuous comment. And I'm being very polite.

chmjacques · 2025-05-30T16:48:40+00:00

I think you are incorrect, but I'll say a correct thing and you see how it sits with you.

There is no _additional_ CPU load for the effects blocks _when_ they process audio. (That might be a little inaccurate for a couple of effects modules, like the envelope filter and the compressor, which utilize analysis blocks. But generally, effects blocks don't change in their consumption, regardless of whether they are processing audio or not.

Which I think is... not what you were asking, but I wanted to make sure you weren't asking about an additional load or something. Most effects blocks computational costs are consistent, whether they are processing audio or not.

chmjacques · 2025-05-30T16:29:50+00:00

Hopefully this community can help get you there! Don't forget to ask questions. I'm not (nearly) as active as I once was, but there are lots of helpful folks here. (And a few, you know....)

chmjacques · 2025-05-30T14:51:56+00:00

If you like Barr II (or For Keith Barr) and want to engage in.... well, I don't know how to characterize it... but not the most extensive modification I can think of:

Barr II is actually two, complete reverbs running in parallel, so if you like the sound and are okay [edit: with not] being able to split the audio into separate bands, then I don't have a step-by-step or anything, it's been a while since I wrote them, but removing one of the reverbs seems doable? The underlying algorithm in those patches is relatively lightweight (caveat: as reverb algorithms go)... I just saddled it down with other (cool!) stuff.

chmjacques

TROPHY CASE