Expressive gesture mappings for MIDI knobs/faders/buttons?

I’m interested in trying to create a more “instrument-y” interface with my Novation LaunchControl XL and VCV Rack. It has the typical buttons, knobs, and faders, but the VCV Rack patching utilities allow me to use them more-than-straightforwardly. For example:

  • I’m inspired by @_js.m_’s “strum” mechanic on faders. (Within a Rack patch, I could calculate a fader’s acceleration and use that as a parameter distinct from fader level.)
  • If a button is pressed quickly enough, it could send a distinct trigger instead of two quick ones (analogous to how a “double-click” message is distinct from two separate clicks, or how a drum flam is considered a distinct “note” not multiple quick hits)

Does anyone have examples or ideas for expressive, innovative MIDI controller macros/mappings like this?

I had fixated on custom hardware/sensors before, but my LaunchControl feels so good already, and I know I can get more gestures out of it with more complicated mappings.

(Side note: the demo video for the LaunchControl seems to pigeonhole it as a mixer—while the -Pad has clearly crossed over to shredable instrument territory! Feels like a missed opportunity…)

I’m thankful for anything this might make you might think of!

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That’s quite a broad and interesting topic.
One can start here (« The Importance of Parameter Mapping in Electronic Instrument Design», Hunt et al. 2002):
https://dl.acm.org/doi/10.5555/1085171.1085207
This article might be stating “obvious” things (although…), but it frames the problem in a useful way. Then there are like 20 years of NIME articles (Proceedings Archive | NIME) in case you haven’t stumbled upon that already.

To answer from a more personal angle, I did focus a bit on “single-fader instruments” at one point. I was not overwhelmed by my findings and would hardly call any of this «innovative» but some ideas in there might click with you.
I still use faders (insert praise for 16n faderbank here) as my primary “expressive” interface with a modular system, but it’s more like “two-faders” instruments now¹, one for the profile of the sound and the other for “secondary” expressive qualities.

The simple “mapping tricks” that i use regularly are:

  • using the same fader to control an instrument’s “main process” and it’s main VCA, ie. the fader has to be moved from 0 for something to start happening (with possibly some slight inertia): this fader is not just mixing in an ongoing continuous voice, but putting the voice in motion as well.
  • map the course of the fader to an arbitrary function that happens to be better suited (to avoid narrow sweet spots).
  • dividing the course of a knob/fader in various zones (that is a big vague, but for exemple such a knob would simply scrub a buffer/sample containing pre-recorded CV)

I tend to tune control depending on the sound i want to get and my expectations of expressiveness, but other approaches (which i’m sure will get shared here) would be interesting.

¹:in most cases, 3 faders controlling a single sound gesture is too much for me to keep track of in an instrumental way

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Really interesting write-up, thanks for sharing. I’d really like to explore these concepts - I felt quite disappointed when I realized buying my 16 knob controller didn’t result in utmost control, but rather frustration that I couldn’t remember what knob affected what parameter :slight_smile: (which to be honest still plauges me with my Grid too!) This more intuitive approach seems great to dive into.


Update: Here’s a real quick first try at making “knobs” (mouse X/Y) react to multiple parameters with varying curves, an empty center point, and differing behaviors (well, directions) +/- the center. Keep your mouse at the center of the screen for silence, nudge it around for noises. Certainly could get more interesting than this, but it’s a start… zones in particular are interesting to me - possibly easier to tackle in Lua for Norns than SC at least with my level of knowledge.

(
// filter pinger
// mouse x controls volume, rate, freq, res, reverb send
// center point is empty
Ndef(\pinger, {
	var mid = 0.5;
	var mx = MouseX.kr(0, 1);

	var mxDir = (mx - mid) * 2; // -1 to 1
	var mxNorm = (mx - mid).abs * 2;  // 0 to 1

	var clickRate = mxNorm * 32;
	var clicker = Impulse.ar(clickRate);

	var pingerFreq = 1000 + (mxDir * 400);
	var pingerRes = 0.8 + (mxDir * 0.18);
	var pinger = DFM1.ar(clicker, pingerFreq, pingerRes, 1);
	var amp = mxNorm.lag(3, 3);

	var reverbIn = amp * amp * amp * pinger; // cubed
	var reverb = FreeVerb.ar(reverbIn, 1, 1, 0.05);

	(pinger * amp) + reverb ! 2
}).play;

// fm drone
// mouse y controls volume, fm, pitch, reverb send
// center point is empty
Ndef(\fmDrone, {
	var mid = 0.5;
	var my = MouseY.kr(0, 1);

	var myDir = (my - mid) * 2; // -1 to 1
	var myNorm = (my - mid).abs * 2;  // 0 to 1

	var modAmount = (myNorm * 20);
	var xmod = LocalIn.ar(1);
	var pitchShift = (myDir * 8);
	var osc1 = Pulse.ar(1440.2 + pitchShift + (modAmount * xmod));
	var osc2 = Pulse.ar(64.7 + pitchShift + (modAmount * osc1));
	var mix = (osc1 + osc2) * 0.5;
	var filterFreq = 50 + (myNorm * 400);
	var voice = DFM1.ar(mix, filterFreq, 0.8, 0.5);
	var amp = myNorm.lag(3, 3);

	var reverbIn = amp * amp * voice; // squared
	var reverb = FreeVerb.ar(reverbIn, 1, 1, 0.03);

	LocalOut.ar(osc2);
	(voice * amp) + reverb ! 2
}).play;
)
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Love this, thank you! Some great general theory, but also a few specific examples I liked:

a wiring mistake by the studentmeant that the ‘volume’ antenna only worked when yourhand was moving. In other words the sound was onlyheard when there was a rate-of-change of position, ratherthan the traditional position-only control. It was unex-pectedly exciting to play. The volume hand needed tokeep moving back and forth, rather like bowing an in-visible violin. … it felt as if your own energywas directly responsible for the sound.

“Ican’t get my mind to split down the sound into these 4finger controls.”

I like the point this makes about complex mapping being both harder and easier to play. Makes me think about the trope of filter sweeps in electronic music, a very linear modulation that makes sense as a performable gesture when your instrument has EQ params. The “filter this” feature on acoustic instruments is a complex result of technique, if it’s flexible at all.

I gotta borrow my friend’s EWI :sweat_smile:

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