I started to make some music using (analog) synths, but I only have monophonic synthesizers and a drum machine. I still need something simple and polyphonic for strings and chords.
I already wrote a simple interactive sequencer in Perl, so why not try to roll my own soft-synth? It's a lot more fun to tinker than to choose an existing soft-synth and read a manual ;-)
project home: https://github.com/mmitch/syndig
Oscillator types can be selected via Program Change messages:
- 000: square
- 001: sawtooth down
- 002: sawtooth up
- 003: triangle
- 004: sine
- 005: noise
- 006: impulse
- 007: square wavelet 25% duty
- 008: square wavelet 50% duty
- 009: sawtooth down wavelet
- 010: sawtooth up wavelet
- 011: triangle wavelet
- 012: sine wavelet
- 013: noise wavelet
- 014: double pulse wavelet
Wavelets are small PCM samples with a length of 8 samples.
Unmapped programs wrap to 000.
To control the ADSR envelope, send Control Change events with the given parameter numbers to change these values:
- 072: release time
- 073: attack time
- 075: sustain level
- 076: decay time
The times map non-linearly from value 000 (0 seconds/off) to value 127
(about 5 seconds).
The sustain level maps linearly from value 000 (envelope off) to value
127 (maximum envelope).
Polyphony mode can be selected via Control Change event for parameter 003. The polyphony mode chooses the note to kill prematurely to make room for a new note when polyphony is at maximum capacity:
- 000: kill oldest note
- 001: kill lowest note
- 002: kill highest note
- 003: kill in a round robin fashion
These Control Change parameters are also honored:
- 007: channel volume
- 120: all sound off
- 123: all notes off
syndig - a simple software synthesizer in C
Copyright (C) 2020 Christian Garbs mitch@cgarbs.de
Licensed under GNU GPL v3 (or later)
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.