Melody player with a Saxophone

Advancing the steps of a sequencer in a non-linear fashion can result in some serious discoveries! While there are many ways to achieve a good result, I tend to take the “programmer” route and understand what my sequencer CAN and CANNOT receive as a triggering gate; for example the Buchla Easel Command step sequencer can be triggered by any MDI note > note #23 and also by note # 0-2 (C to D), or as I interpret it: the sequencer DOESN’T advance when receiving midi notes #13-23 (lower than #13 other modules get triggered). This is very important data and you should go look it up in your sequencer manual!
Why is it important?! In my previous post I speak about organic polyrhythms and how to be economical about our multiple sequences/rhythms, this time I want to expand that concept and explore just how a very short sequence (3-4-5 steps) can be stretched and made interesting by triggering its steps with a non grid-like trigger source.

Let’s take as an example the following non-linear trigger source pattern (by non-linear I mean a pattern that is not a series of triggers at the same subdivision, e.x. a grid of 8th notes or 16th):

Notice it has three 8th note and one 8th rest, the rest is the KEY! In my case to simulate this pause I’ll send to my sequencer a trigger that it DOESN’T recognize (midi notes #13-23?!) so it won’t advance.
Then let’s use this trigger source pattern to advance our step sequencer, let’s say that our sequencer has been programmed with the following pattern:

Now, finally, we get to observe the main concept in action. Let’s go ahead and program the sequencer so that it advances ONLY when the trigger source pattern is outputting a trigger, meaning the main sequence WON’T advance whenever the trigger source pattern is on a rest.

The result, in this particular case, will be the following:

As you can see, the top line is our trigger source pattern, and at the bottom the result of the triggered steps in our sequencer, I labeled the step # below each trigger that will be recognized by the sequencer with the step it will actually trigger. et voilà!
It immediately evokes me some sort of rhythmic ostinato/clave that could well be the source of your entire track! In the video I’m playing a similar clave together with a Caribbean ostinato, will go in depth in the next post on how to setup the 2 and where the 1 is =)

Organic polyrhythms are hard to obtain. Charles Cohen was a master of that and after having had his records on loop for some time I started to notice something interesting: how does he achieve polyrhythmic structures with only one sound?! easy, don’t repeat the common accents between the 2 (or more) rhythms, let me explain.
I’m fully aware of Cohen’s use of the 16 seconds delay to drive the Easel Sequencer, but I will deal with this in a future post. For now I just want to state something obvious that might get overlooked in drum machines rhythmic practice: what “rhythmic melody” does any given polyrhythm have?!
Once this is clear, it’s possible to structure a sequence that follows this sort of melody utilizing just one voice/sequence, freeing up something else in your system to add other layers.
2 against 3 in 8th notes (L = low sound, H = high sound, R = rest):
L R H L H R
or in 16th:
L R R R H R L R H R R R

Also, in this video excerpt I’m practicing a rhythmic structure with a series of nested 3 against 4; the main one comes from the arp sent from the MIDI keyboard that goes first through a custom MIDI Mod Matrix and then to the Easel Command triggering the E.Gen and SVS, both set to a 3 against 4 pattern and triggering respectively LPG 1 and 2. Exploiting the “dead” octave of the Easel keyboard MIDI input to add a rest from the main sequence. The rest is delay moving from one subdivision to another + the SVS doubling the accents, timbre etc… mostly through the MOD Matrix,

An Interesting patch that could turn into something usable… AM Modulation is a great tool for extracting formant-like sounds because of the way it “simply” produces sidebands with frequencies at carrier+mod and carrier-mod. Ignoring the negative component (in this case it’s too low even to hear sometimes!) we are left with the positive component + fundamental (the carrier) and some extra frequencies due to the imperfect ratios dialed by hand. All of this sounds kinda human-like! I’m using my trusty Buchla 208c but I’m sure it could work as well with any AM synth.

The patch: set the carrier and the modulator roughly a major 6th apart, usually the carrier is the lower one. This should be your lowest formant imitating an Italian “U” (Eng. “oo”), from that slowly increase the pitch of the modulator looking for the other vowels! It helps to gate the carrier so you can shape its volume and sculpt the attack and decay of the sound. It will immediately resemble a human pronouncing a vowel-like sound, while also speeding up the vowel hunting process.