Random sequencer


Now that I no longer have an esx, my arduino board was useless (see http://mutable-instruments.net/forum/discussion/5766/midi-clock-offset- ) so I decided to write something useful for it: a 16-step sequencer which allows me generate random sequences for my music project (live techno duo Conformance https://soundcloud.com/conformance/conformance-live-le-chantier-rennes-2015-11-06). So here it is: https://github.com/desfrenes/acidrandomizer (Works best with typical 303 bass sounds).

This is practically my first script for a hardware device so it’s probably badly written but so far it works as I intended it. I liked the experience a lot and wish I can keep on making that sort of stuff… maybe write a full-blown sequencer with pots and switches one day :slight_smile:

What Arduino board do you have?

If you have one that can be used as a mouse or keyboard for your computer, you can use it as a midi device over USB. This would let you test out your parameters with midi CC messages instead of hooking up lots of pots and switches.

It’s Arduino Uno. I already ordered a couple of analog multiplexers to extend it.

some random acid stuff: https://www.youtube.com/watch?v=LCqmuGLBt-U

I ordered some pots, 6N137 and other parts… now it’s time to turn this idea in a nice midi module.

I have worked on the case: https://www.dropbox.com/s/pddvk25giyw984f/random_seq_case.jpg?dl=0

I can’t get the 6N137 to work… I must be doing something wrong. I tried to replicate the shruti midi in: https://www.dropbox.com/s/rhj6jr5svqmh0fr/random_seq_6N137.jpg?dl=0

Any obvious error here ?

Pretty sure the diode between pin 2 and 3 is reversed.

Thank you for your help.

Schematics says diode() goes to pin 3, right ? I thought the diode() was the one with a circle ?

Looks reversed to me too.

ah ! I’m dumb :slight_smile:

Thank you, I’ll try this tonight :slight_smile:

Yes ! All good… thank you !

Back to the perfboard now :slight_smile:

Allright, thanks to you I could implement 4 of the 8 parameters I have planned. Little demo: https://www.youtube.com/watch?v=-_zQQ9XGhoE

(audiothingies P6 for sound)

Looks really fun to play!

Nice idea. Also fits well to one of my projects.

I wanted to follow you on Google+, but I am somehow not allowed to add you. My profile is:

here’s how it works:

  • Lowest note: select the lowest note that will be played
  • Highest note: select the highest note that will be played
  • Split note: any note played above this note will be sent to the secondary midi channel
  • Scale: select one of the various scale (C-based: minor, major, penta, etc…)
  • Sequence resolution: 1/1, 1/2, 1/4, 1/8, 1/16, 1/32
  • Sequence length: from 1 step to 16 steps
  • Density: controls the amount of slides and rests. The higher the value, the less rests and slides
  • Random probability: Controls the probability for the next step to be randomized. 0: step will stay as is. Max: step will be randomized. Anything in between for self-evolving sequence :slight_smile:

Sorry Karg, I don’t understand much of Google+. I have a facebook account, mostly about techno/house music: https://www.facebook.com/theo.stomp.3


  • finish the code
  • close the case
  • have fun at a party with the unit
  • learn how to make a pcb
  • make this a eurorack module that spits dual cv/gate

More random sequence action (acid bass by shruti, organ by p6): https://www.youtube.com/watch?v=aAL5Njb0k58