MultiMidiSequencer

A software sequencer that allows for multiple different sequences running at the same time using MIDI

The Drum Pattern Sequencer

The drum pattern sequencer plays patterns encoded in ascii-based text files. It is inspired by the programming principles of famous drum machines like the Roland TR808 and TR909 and it's clones, the Behringer RD-8 and RD-9.

A pattern is encoded according to the following rules in a text file:

• a "sequencer drum pattern" is stored in a file with the ending .sdp
• a line starting with a # is a comment and ignored for the pattern playing
• an empty line is ignored
• a "track line" represents an "instrument" with a dedicated pattern to be played
  • a track line starts with the instrument shortcut (e.g. BD1 for bass drum 1) and is followed by a space
  • the instrument shortcuts are defined in a Drum MIDI Mapping file (.dmm, see folder DrumMidiMappings) and is an alias for a MIDI Note value
  • the second part after the instrument is the pattern that the instrument shall play encoded with characters, with each character representing a 1/16 note of a 4/4 beat.
  • tracks can have different length; the tracks that are shorter than others in the same file will be repeated as often as it matches the length of the longest track; to indicate that really nothing shall be played you have to actively encode that with . (off) characters for the length of the longest track.
  • here is the character encoding:

Drum Pattern Characters:
        - : continue note   Send no note
        . : off             Note off
        + : ghost note      Note on with velocity 10
        s : soft            Note on with velocity 60
        m : medium          Note on with velocity 100
        x : hard            Note on with velocity 120

Here is a drum pattern example:

file: ./DrumSeqPatterns/basic_drum_2.sdp

# Sequencer Drum Pattern
# Basic Drum Pattern 2
# by Dr. Markus Voss

BD1 x.....s.x.......x.........x.....
SN1 ....m-......m-......m-......m-..
CHH xsss
CR1 x-..............................

This example is a pattern of 2 bars in a 4/4 beat described with 32 1/16 notes. BD1 is the pattern for the base drum (kick drum), SN1 is for the snare drum, CHH is for the closed hi-hat and CR1 is the crash cymbal. Note that here the pattern for the closed hi-hat has only 4 characters, representing 4 1/16 notes. This means that during the whole two bars this pattern is repeated 8 times, matching the length of 32 notes for the whole pattern which is defined by the longest track (which are basically all the others that are all 32 notes long). Principally, you can have as many tracks in a file as you want.

See examples of further drum patterns in the folder DrumSeqPatterns of this repository.

Example with a Korg Wavestate

Check out this repo on your PC (MAC).

Import the performance ./PresetsExtDevices/KorgWavestate/MV Simple Drumkit.wsperf that is here in the repository into your Korg Wavestate using the Wavestate Editor/Librarian Software and then switch to that performance.

On your PC (MAC), execute the following command:

 python3 multimidiseq.py -m ./DrumMidiMappings/Korg_Wavestate_Drm_WS_Drum_Kit.dmm ./DrumSeqPatterns/basic_drum_2.sdp 

The file Korg_Wavestate_Drm_WS_Drum_Kit.dmm contains the MIDI mapping to the Wavestate with the given performance.

The file basic_drum_2.sdp contains the beat patterns that will be played.

Example with the Singular Sound Beat Buddy Pedal

Connect the Beat Buddy MIDI-in to your Audio interfaces MIDI-out.

Then, on your PC (MAC), execute the following command:

 python3 multimidiseq.py -m ./DrumMidiMappings/BeatBuddy.dmm ./DrumSeqPatterns/basic_drum_2.sdp -b 80

This makes the Beat Buddy play the drum pattern defined in the file ./DrumSeqPatterns/basic_drum_2.sdp at a tempo of 80 bpm.

Example with a SW synth like e.g. the Korg native SW synths

Instead of selecting a real MIDI output port, you have to create a virtual SW output port. This will be created by giving the additional argument --virtualout True to the command line tool like this:

python3 multimidiseq.py -m ./DrumMidiMappings/BeatBuddy.dmm ./DrumSeqPatterns/basic_drum_2.sdp -virtualout True

Now the pattern will be played on a virtual SW MIDI output called "MultiMidiSequencer". Select that port in your SW synth's settings as MIDI input source.

Playing a track

The MIDI device mapping is referenced from within the .sst file.

 python3 multimidiseq.py ./Tracks/song1_drums_verse.sst 

Pattern Sequencer with MultilineNotePattern

You can define several parallel "lines" of notes, each of different lengths, that get repeated indepentently. The velocities are similar to the drum patterns, but directly after the velocity the MIDI note value is encoded. See the example .mnp file here:

 python3 multimidiseq.py ./MultilineNotePatterns/song1_verse.mnp 

Installation Requirements

• needs Python3 (tested with version 3.8.2; definitely a version >3.2 needed as argparse is used) and pip3 (usually comes with Python)
• install python-rtmidi by executing: pip3 install python-rtmidi

Development Notes

This code is

based on: drumseq.py

from here: https://github.com/SpotlightKid/python-rtmidi/tree/master/examples/drumseq

which is itself based on:

MIDI Drum sequencer prototype, by Michiel Overtoom, motoom@xs4all.nl (http://www.michielovertoom.com/).

The code will subsequently be reworked into the idea that I have in mind.

The ideas for the sequencers that will be implemented are influenced by "real world sequencers" (but are adopted to my ideas) from:

• Korg Wavestate
• Behringer RD-9 (which itself is a clone of the Roland TR909)
• Korg Minilogue XD
• Roland J-6
• and several others that I saw being programmed in YouTube videos

Enjoy!

Dr. Markus Voss