Minimalistic generative composition with three piano-like voices that shift in and out of phase with each other.
After seeing a few videos on synchronizing metronomes (Benn Jordan’s was great!) I wanted to try a patch where multiple LFOs running at different rates affect each other in a similar way.
This is the result; three simple sine wave voices (with some feedback FM for a piano-like texture) each triggered by their own LFO, but the LFOs are influencing each other in such a way that they WANT to stay more-or-less in sync, but sometimes escape each others grasp and flip into a counterpoint rhythm. It’s a very weird but hypnotizing effect, like a strumming pattern that sometimes fluidly morphs!
The pitch sequences for each voice are just simple shift register sequencers, just 2 or 3 steps long and with a very low flip chance, but the interplay of such few notes combined with the phase shifting of the LFOs (and a delay with a lot of feedback!) provides mesmerizing minimalistic melodies! There is a second set of sequencers for determining note velocity, adding another layer of humanization to the composition.
The name ‘chronostasis’ is a term for a really interesting temporal illusion, where something seems to last longer than it really does (e.g. when changing your gaze to look at an analog clock and the hand seems to remain still for more than one tick, try it!). Anyway, I thought it was very appropriate for this weirdly hypnotic patch. Sit back and relax!
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[OVERVIEW]
-Input/Output: Stereo input (goes only through the reverb), Stereo out
-CPU load: Around 101%
-Build: Initial version built with firmware 2.80
-MIDI: Controls are NOT YET set to CCs (I normally use channels 21/36, see CONTROLS section for details).
-CV Inputs: Unused.
-CV Inputs: Unused.
[REVISIONS]
1.0: Initial patch.
[CONTROLS]
All the main controls are on PAGE0 and are labeled and starred (see below for a “Picture Manual” in the comments). The Stereo Output module with gain parameter is on PAGE1.
RATE (sets rate of the main LFO)
DELAY TIME (speaks for itself)
FLIP CHANCE (set the chance that new notes are injected)
LPF (low pass filter)
SPREAD (sets how much the notes are apart)
HARMONY (sets the harmonic interval offset for the 2nd and 3rd voice)
ATTACK/DECAY (speaks for itself)
LOWEST (sets the root pitch; use in conjunction with SPREAD to set desired pitch range)
VELOCITY (sets the average velocity of notes)
LOCK SYNC 2ND / LOCK SYNC 3RD (toggles to lock the 2nd and 3rd voice to the main LFO; doesn’t FULLY lock at some speeds but hey, that’s life…)
ZEBU LEFT button = Toggle 2nd voice.
ZEBU LEFT button = Toggle 3rd voice.
ZOIA stompswitches = Unused.
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[PATCH STRUCTURE]
I’m not gonna explain the voices or the Turing-machine shift register sequencers here, that’s been done before. Instead, I’ll focus on the most unique feature here, the syncing LFOs:
We start with one LFO that is steady and one that is slower. We rectify both LFOs, then multiply them with each other, and we use the resulting value to increase the rate of the slower LFO a little bit.
So, when they are in-phase (or 180 degrees inverted), the peaks coincide and the multiplication is relatively high, speeding the slower LFO up a bit. When they are NOT in phase, the multiplication is very low, so the slow LFO isn’t sped up, until the peaks start to coincide again. This feedback mechanism keeps the two LFOs at the same pace for a while when the peaks are more-or-less aligned but does allow the slow LFO to sometimes ‘escape’ the gravity of the steady LFO and flip to an inverted phase.
Now we just repeat the same thing but for a third LFO that’s slightly faster than the steady LFO, but instead we slow it down a bit when the peaks coincide.
I’ve tried to make it a feedback circle (so the ‘steady’ LFO is in fact also modulated by the other two), but I couldn’t tweak it so they actually did anything interesting, so I just kept the one LFO at a fixed rate.
So, now we have some pendulum-like syncing LFOs… what to do with them? Well, I just let them trigger simple voices and I tweaked the LFO feedback values so they only rarely ‘escape’, which makes the notes trigger in a very satisfying way (to me at least). This does mean the rate over which the patch can function is limited (and the ‘Lock’ toggles may not always lock perfectly at slower rates), but it’s still quite fascinating to listen to.
I’ve also used this whole phase multiplication mechanism as an obscure ducking mechanism to reduce the level of any voice when it’s not in sync, making the transitions phase transitions a bit smoother.
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[TIPS/TRICKS]
>>> Adjust the SPREAD, HARMONY and LOWEST values to your taste, and increase FLIP CHANCE if you want more lively (=less hypnotic) compositions.
>>> If you change the RATE, you’ll have to manually adjust DELAY TIME as well to match, but it does mean you can get nice ‘in-between’ time divisions.
[THOUGHTS/IDEAS/PLANS]
This patch is done, no future plans.
If there’s any bugs/questions/remarks/requests or suggestions for improvement, please let me know!
Enjoy!
(Image: Ben Simon Rehn)
Picture Manual:
Attachment Manual-Chronostasis-63c6ca9273326.jpg