A modular synthesizer for the command line written in golang.
- Install and setup Go
- Clone the repository
git clone git@github.com:iljarotar/synth.git- Install
cd synth
make build
cp bin/synth /usr/local/bin # or somewhere else in your PATHRun
synth examples/sequencer.yamlto listen to an example.
Patches for the modular synthesizer are provided in yaml format. A patch contains configurations for all modules that you want the synthesizer to play. When you modify and save a patch while it is being played the synthesizer will reload the file.
This section explains all available modules and provides example configurations. To see some more examples see the examples directory.
Each module must have a unique name across all modules.
This name is used as a reference in other modules, e.g. when a module is used as a CV or modulator.
If a module is provided with a CV its static value is ignored.
For example, if you pass a CV to an oscillator this CV will provide the oscillator's frequency and the statically assigned frequency will be ignored.
If a module is provided with a modulator it will modulate a parameter around its static or CV-provided value.
For example, a mixer with a gain of 0.5 and a sine wave as a modulator will output a tremolo around the gain value of 0.5.
Each module outputs values in the range [-1, 1].
When using a module as a CV or modulator for some parameter of another module the range [-1, 1] is mapped to the range of the respective parameter.
Example:
An oscillator's frequency is in the range [0, 20000].
A modulator that outputs values in the entire possible range of [-1, 1] will modulate the oscillator's frequency in the entire range [0, 20000].
To control the amount of modulation you must pass the modulator through a mixer and attenuate its gain.
The following yaml file provides examples and explanations for all configuration parameters.
# my-patch.yaml
# main volume control
# range [0, 1]
vol: 1
# name of the module to output
out: name-of-main-module
# adsr envelopes
envelopes:
# the unique module name to be used as a reference in other modules
envelope:
# attack length in seconds
# range [1e-15, 3600]
attack: 0.1
# decay length in seconds
# range [1e-15, 3600]
decay: 0.05
# release length in seconds
# range [1e-15, 3600]
release: 2
# peak level targeted during the attack phase
# range [0, 1]
peak: 1
# sustain level
# range [0, 1]
level: 0.75
# name of the module to use as a gate signal
# when gate output changes from negative or zero to positive the envelope is triggered
# while gate is positive the attack, decay or sustain phases are active
# when gate output changes from positive to negative or zero the envelope is released
gate: name-of-gate-module
# filters of type low pass, high pass or band pass
filters:
# the unique module name to be used as a reference in other modules
filter:
# one of LowPass, HighPass, BandPass
type: BandPass
# critical frequency
# range [0, 20000]
freq: 500
# band width in case of type BandPass
# ignored for other types
width: 50
# cv for `freq`
cv: name-of-cv
# modulator for `freq`
mod: name-of-modulator
# name of the module whose output will be filtered
in: name-of-input-module
# gates can be used as gates for envelopes or sequencers or as triggers for samplers.
gates:
# the unique module name to be used as a reference in other modules
gate:
# beats per minute controls the tempo of the gate signal
bpm: 260
# cv for `bpm`
cv: name-of-cv
# modulator for `bpm`
mod: name-of-modulator
# binary signal
# each negative or zero value will be mapped to `-1`, each positive to `1`
signal: [1, 0, 0, 1, 0, 1, 1, 0, 1, 0]
# mixers combine outputs of multiple modules and control their output levels
mixers:
# the unique module name to be used as a reference in other modules
mixer:
# gain in range [0, 1]
gain: 0.5
# cv for `gain`
cv: name-of-cv
# modulator for `gain`
mod: name-of-modulator
# mapping of module names to their corresponding gain levels
# take care not to exceed 1 as the output is limited not to exceed `[-1, 1]`
in:
name-of-first-module: 0.5
name-of-second-module: 0.25
# noise modules simple output random values
noises:
# the unique module name to be used as a reference in other modules
# a noise module doesn't have any parameters to configure, so pass an empty object `{}`
noise: {}
# oscillators output basic wave forms like sine waves, triangles, etc.
oscillators:
# the unique module name to be used as a reference in other modules
oscillator:
# one of Sine, Square, Triangle, Sawtooth, ReverseSawtooth
type: Sine
# frequency in range `[0, 20000]`
freq: 440
# cv for `freq`
cv: name-of-cv
# modulator for `freq`
mod: name-of-mod
# static phase shift in percent of one period
# range `[-1, 1]`
phase: 0.75
# pan modules are used to add stereo balance
pans:
# the unique module name to be used as a reference in other modules
pan:
# specifies how big a portion of the signal is output through the left and right channels
# range `[1-, 1]`
# a value of `-1` places the signal completely to the left, `1` places it to the right
pan: -0.5
# cv for `pan`
cv: name-of-cv
# modulator for `pan`
mod: name-of-mod
# sample and hold modules
samplers:
# the unique module name to be used as a reference in other modules
sampler:
# name of the module that is being sampled
in: name-of-input-module
# name of the trigger module
# when the trigger's output value changes from negative of zero to positive a new sample is taken from the input modules output
trigger: name-of-trigger-module
# sequencers can be combined with oscillators or wavetables to create melodic sequences
sequencers:
# the unique module name to be used as a reference in other modules
sequencer:
# a seqeunce of notes in scientific pitch notation
# flats are denoted by `b`, sharps by `#`
# a note is separated from its octave by an underscore
# minimum octave is 0, maximum is 10
sequence: ["a_4", "eb_3", "c#_5"]
# when the trigger's value changes from negative or zero to postive the next note in the sequence is triggered
trigger: name-of-trigger-module
# base pitch from which to calculate all other frequencies
pitch: 440
# tranpose the whole sequence by any number of semitones
# range `[-24, 24]`
transpose: -4
# if `true` the notes in the sequence will be played in random order
randomize: true
# pass any values to a wavetable to create arbitrary signals
wavetables:
# the unique module name to be used as a reference in other modules
wavetable:
# frequency in range `[0, 20000]`
# specifies how many times per second the entire signal given in the `signal` field will be played
freq: 440
# cv for `freq`
cv: name-of-cv
# modulator for `freq`
mod: name-of-mod
# an arbitrary signal
# the signal can have any length
signal: [-1, 0, 0.25, -0.3, 0.8, 1]On first run, synth will create a synth/config.yaml file in your default config directory.
Modify this file to adjust the configuration.
Run synth -h to see where this file was placed.
You can also override single parameters via command line flags.