MidiSeq -- polyphonic MIDI step sequencer

Here is yet another firmware variant for MidiGAL. This time it’s a polyphonic MIDI step sequencer with some great features: note step advance, step modifiers (tie, half, strum, and accent), super stable internal clock, nice swing and two modulation sources with velocity, after touch and CC destinations.

Things I like about it:

  • polyphony – it’s a lot of fun playing with chord progressions.
  • strum – chords played as arpeggios within the sequence, especially when interval between strummed notes is longer then step duration results in very interesting sequence permutation somewhat similar to what has been previously done with rhythmic delays.
  • swing – having rock solid clock and swing adjustable at 0.1% increments opens up a lot of sweet groove points.
  • modulations – you can never have enough of them!
  • ability to change sequences on the fly without stopping the sequencer
  • ability to step through sequencer by playing notes on the controller keyboard – with transposition. You can literally “play” sequences!
  • ability to be controlled with pretty much any MIDI controller keyboard out there – having external knobs and buttons really helps.
    Although MidiSeq is a polyphonic sequencer it works just as well with monophonic sequences. Think of SH-101 sequencer on steroids :wink:

Great !
Any chance to see a MidiRex-ish looper firmware in the future ?

Yeah, there is a plan to port MidiSeq code to MidiREX hardware and make it a 4 channel step sequencer.

With 16x2 LCD, 2 buttons for playback and recording control, and 4+1 buttons for channel control and LEDs it will be nice to use.

Actually my question was about porting a stripped-down MidiREX firmware to the MidiGAL :stuck_out_tongue:

@dubtoms This is not possible because MidiGAL’s external EEPROM is too slow, and MCU RAM is too small even for a stripped down MidiREX. Also, single button/enoder UI will not be usable.

> Yeah, there is a plan to port MidiSeq code to MidiREX hardware and make it a 4 channel step sequencer.


Is there a chance in midiseq mode the midirex’s footswitch input could receive triggers and advance the sequence like a sh101?

@soup that’s exactly the plan. I also plan to add similar support to MidiGAL MidiSeq – you can already trigger and advance steps with NoteOn events, so the fun of manual step pushing is already there, but only via MIDI. Since there are 4 currently unused I/O ports, i’d like to have them doing DYN Sync24 I/O … not sure it will be technically possible since 95% of Atmega328p program memory is already used. That would not be a problem for MidiREX step sequencer implementation since it uses Atmega644p with twice as much memory.

Just a quick update about cases since this thread is active, prototype went to laser cutting yesterday. Depending on interest, I may do another run like I did for MidiREX with a full kit off all the parts and case. I’m also working on a midigal + midithru mashup case

I might be interested in a case…depending on how the proto looks like :slight_smile:

same here

gal + thru mashup makes me very excite. yes, yes.

now if it only did midi thru on two inputs, id be set :smiley:

I would also be interested in a full kit + case.

Im interested as well!

and here we go:

Let me know if you intend to sell MidiGAL enclosures alone or (better) share laser-cutting files :wink:

depends on interest. What I usually do is do a small run as a kit with all the correct hardware then release the files

would love to get in on a gal enclosure. :slight_smile:

Looks great! Will clear acrylic be the only option? I loved the black matte case I got from you before.