This repository contains Python MIDI synthesizers which can be played in real-time, e.g. from a USB MIDI keyboard, a MIDI file, an on-screen MIDI keyboard such as VMPK or the included midi_keyboard.py.
Audio demos are available at the PySynth homepage.
There are also various other MIDI-related scripts in this repository, some of which require PyGame to open a window and display some graphics. MIDI is still handled by mido, not PyGame.
If you need a source of MIDI events to test the synths with, see my triadex-muse repository, a random music generator in Python.
They all require PyAudio (for audio output) and mido (for MIDI event handling):
- multi_synth.py: 8-note polyphonic additive synthesizer
- multi_wave.py: 12-note polyphonic wavetable synthesizer
- epiano.py: 8-note polyphonic DX7 FM e-piano synthesizer (ported from PySynth E; code based on multi_synth.py)
- midi_synth.py: simple monophonic additive synthesizer
Default polyphony settings are fairly low to make sure the synths can run on older hardware, but can be changed in the scripts if desired.
Multi_synth.py and midi_synth.py produce a piano-like timbre using three sine waves like PySynth A and an exponential decay like PySynth B, so they sound very similar to PySynth A and B. Multi_wave.py on the other hand loads a wavetable with a guitar-like sound by default.
- midi_keyboard.py: an on-screen MIDI keyboard which can be used to play the synths or to show incoming MIDI notes from other sources
- falling_notes.py: piano trainer with falling MIDI notes. Press Space to pause, press F or S to go faster/slower.
- scale_explorer.py: show different musical scales on a piano keyboard; use cursor keys to navigate.
- midi_play.py: play a MIDI file; can be used to play back a MIDI file to these synthesizers
- midi_play_slow.py: play a MIDI file slowly
- pitch_range.py: show pitch range of a MIDI file (highest/lowest notes), so you can see if a piece is playable on your MIDI controller or needs a bigger octave range.
- studio.py: a simple MIDI recording studio. By default, MIDI program 0 is where you play and where all notes are recorded and program 1 is for control mode. Playing a C in control mode shows info, playing D replays all notes in memory, and playing E saves as a MIDI file to the current directory.
The wavetables directory contains some other wavetables for multi_wave.py. There also some Python scripts in that directory that demonstrate how to create wavetables.
It is also possible to convert wavetables from other synthesizers. Often these are in 32-bit floating point format, so they need to be exported as 16-bit integer WAVs in Audacity. The number of samples per waveform needs to be set in multi_wave.py. Also, the volume should be set low enough so that multi_wave.py does not crash even when many notes are playing simultaneously.
If you hear crackling audio from these scripts (or get no audio at all), you might want to first quit the Python synth and then
- quit other applications, especially web browsers.
- increase audio buffer size (BSIZE) in the scripts or reduce maximum polyphony (MAXPOLY).
- make sure you are running a recent Python version, because Python performance tends to improve with each release.
- 2010_mavericks_competition.jpg: photo by Shalom Jacobovitz; derivative work: Brocken Inaglory, CC BY-SA 2.0 https://creativecommons.org/licenses/by-sa/2.0, via Wikimedia Commons
