Make xenharmonic music and explore musical tunings.
Resources
Overview
microwave is a microtonal modular waveform synthesizer with soundfont rendering capabilities based on:
- tune – a microtonal library
- Nannou – a UI framework
- FluidLite – a soundfont renderer
- fluid-xenth – a microtonal wrapper around FluidLite
It features a virtual piano UI enabling you to play polyphonic microtonal melodies with your touch screen, computer keyboard, MIDI keyboard or mouse. The UI provides information about pitches and just intervals in custom tuning systems.
Demo
Download / Installation
Option A: Download a precompiled version of microwave for the supported target architectures:
Option B: Use Cargo to build a fresh binary from scratch for your own target architecture:
# If you are using Linux: Make sure all dev dependencies are installed.
# On the CI environment (Ubuntu 20.04) we only need to add one library:
microwave should run out-of-the box on a recent (Ubuntu) Linux, Windows or macOS installation. If it doesn't, the problem is probably caused by the Nannou framework. In that case, try following these instructions.
Usage
Hint: Run microwave with parameters from a shell environment (Bash, PowerShell). Double-clicking on the executable will not provide access to all features!
This should spawn a window displaying a virtual keyboard. Use your touch screen, computer keyboard or mouse to play melodies on the virtual piano.

MIDI in/out
To enable playback via an external MIDI device you need to specify the name of the output device and a tuning method. The available tuning methods are full, full-rt, octave-1, octave-1-rt, octave-2, octave-2-rt, fine-tuning and pitch-bend.
To listen for events coming from a external MIDI device you only need to specify the name of the input device:
Soundfont Files
For playback of sampled sounds you need to provide the location of a soundfont file. The location can be set via the environment variable MICROWAVE_SF_LOC or the command line:
If you like to use compressed sf3 files you need to compile microwave with the sf3 feature enabled. Note that the startup will take significantly longer since the soundfont needs to be decompressed first.
Modular Synth – Create Your Own Waveforms
On startup, microwave tries to locate a waveforms file specified by the --wv-loc parameter or the MICROWAVE_WV_LOC environment variable. If no such file is found microwave will create a default waveforms file for you.
Let's have a look at an example clavinettish sounding waveform that I discovered by accident:
name: Funky Clavinet
envelope: Piano
stages:
- Oscillator:
kind: Sin
frequency: WaveformPitch
modulation: None
out_buffer: 0
out_level: 440.0
- Oscillator:
kind: Triangle
frequency: WaveformPitch
modulation: ByFrequency
mod_buffer: 0
out_buffer: 1
out_level: 1.0
- Filter:
kind: HighPass2
resonance:
Mul:
- WaveformPitch
- Envelope:
name: Piano
from: 2.0
to: 4.0
quality: 5.0
in_buffer: 1
out_buffer: AudioOut
out_level: 1.0
This waveform has three stages:
- Generate a sine wave with the waveform's nominal frequency F and an amplitude of 440. Write this waveform to buffer 0.
- Generate a triangle wave with frequency F and an amplitude of 1.0. Modulate the waveform's frequency (in Hz) sample-wise by the amount stored in buffer 0. Write the modulated waveform to buffer 1.
- Apply a second-order high-pass filter to the samples stored in buffer 1. The high-pass's resonance frequency is modulated by the envelope named
Pianoand ranges from 2F to 4F. Write the result toAudioOut.
To create your own waveforms use the default waveforms file as a starting point and try editing it by trial-and-error. Let microwave's error messages guide you to find valid configurations.
Live Interactions
You can live-control your waveforms with your mouse pointer or any MIDI Control Change messages source.
The following example stage defines a resonating low-pass filter whose resonance frequency can be controlled with a MIDI modulation wheel/lever from 0 to 10,000 Hz.
Filter:
kind: LowPass2
resonance:
Control:
controller: Modulation
from: 0.0
to: 10000.0
quality: 5.0
in_buffer: 0
out_buffer: AudioOut
out_level: 1.0
Feature List
- Sound features
- Built-in modular waveform synthesizer with physical modeling synthesis
- FluidLite soundfont renderer
- External synthesizer via MIDI-out
- Microphone / aux input
- WAV recording
- Built-in modular waveform synthesizer with physical modeling synthesis
- Control features
- Sequencer / piano keyboard via MIDI-in
- Computer keyboard (configurable isomorphic layout)
- Touch Screen
- Mouse
- Channel events (pitch-bend, modulation, pedals, aftertouch, etc.)
- Polyphonic events (key pressure)
- LF sources (envelopes, time slices, oscillators, etc.)
- Sequencer / piano keyboard via MIDI-in
- Effects
- Low-pass
- 2nd order low-pass
- High-pass
- 2nd order high-pass
- Band-pass
- Notch filter
- All-pass
- Reverb
- Spatial delay
- Rotary speaker
- Microtuning features
- Custom scales
- SCL imports
- KBM imports
- Tuning-dependent automatic isomorphic keyboard layouts
- Customizable second visual keyboard (
--kb2option) - MIDI-out retuning via different tuning message types
- Display frequencies and rational number approximations
Help
For a complete list of command line options run
License
microwave statically links against fluidlite for soundfont rendering capabilities. This makes the binary executable of microwave a derivative work of fluidlite. fluidlite is licensed under the GNU Lesser General Public License, version 2.1.