synth 
A polyphonic Synth type whose multiple oscillators generate sound via amplitude and frequency envelopes.
Features
- Sine, Saw, SawExp, Square, Noise and NoiseWalk waveforms.
- Amplitude and frequency envelopes with an unlimited number of points.
- Unlimited number of oscillators (each can have unique waveforms and amplitude and frequency envelopes).
- Monophonic and Polyphonic modes (unlimited number of voices).
- Simple
note_on(pitch_in_hz, velocity) and note_off(pitch_in_hz) methods.
- Per-channel amplitude and a stereo panning helper method.
- "Stereo spread" for automatically spreading multiple voices evenly across the stereo image.
- Per-voice portamento.
- Per-voice detuning.
- Multi-voice (unison) support in Mono mode.
- Legato and Retrigger Mono modes.
- Warbliness Oscillator builder method that uses gaussian noise to model the "warped-old-hardware-synth" sound.
- Uses sound_stream and its Sample trait and in turn is generic over any bit-depth or sample format.
Rust
for event in stream.by_ref() {
match event {
Event::Out(buffer) => synth.audio_requested(buffer, SETTINGS),
..
}
}
See an example here.
PortAudio
synth uses PortAudio as a cross-platform audio backend. The rust-portaudio dependency will first try to find an already installed version on your system before trying to download it and build PortAudio itself.
License
MIT - Same license as PortAudio.