bleep

Hobby 8bit/16bit synthesizer/sequencer that can also be used as a virtual MIDI device.

I don't really have any goals for this project, but it's #instructive.

Demo songs / Progress

Old examples first:

1. basic wave forms and delay
2. the shabbiest percussion channel
3. stereo, 16bit, tremelo
4. granular synthesis, sequencer, automations, euclidian rhythms

Features

Things that generate waveforms (generators/):

• Sine wave oscillator
• Square wave oscillator
• Sawtooth wave oscillator
• Triangle wave oscillator
• Pulse wave oscillator
• White noise generator
• .wav playback
• Grain generator
  • Configurable grain size
  • Configurable birth rate
  • Configurable density/nr of generators
  • Configurable speed (=position in sample)
  • Position randomization
  • Windowing functions
  • TODO: pitch control (= grain playback speed)

Things that wrap things that generate waveforms (generators/derived/):

• ADSHR envelopes (attack, decay, sustain, hold, release)
• Transposing generator
• Combining multiple generators into one
• Harmonics generator
• Vocoder
• A filtered generator (see below)

Things that filter (filters/):

• Overdrive filter
• Distortion filter
• Delay filter
• Flanger filter
• Tremelo filter
• First order low pass filter
• Convolution filter
• Low Pass Convolution filter
• High Pass Convolution filter
• Band Pass Convolution filter

Things that mix:

• Channels (channels/)
• Mixer (synth/)

Things that control things that mix:

• Sequencer (sequencer/)
  • Automations

Things that MIDI (midi/):

• MIDI note on, note off, program select, pitch bend
• Basic percussion channel
• Registers as virtual midi device

Things that output:

• .wav output (--record)
• "Realtime" PortAudio output
• Mono or stereo

Usage

Bleep uses Go modules and requires Go 1.11+

git clone github.com/bspaans/bleep
cd bleep
go run main.go

Use --help to see the various options and modes.

Run sequencer patterns

go run main.go --sequencer examples/sequencer_1.yaml

Change instruments banks on sequencer patterns

go run main.go --instruments examples/bank.yaml --percussion examples/percussion_bank.yaml --sequencer examples/sequencer_1.yaml

Record sequencer patterns

go run main.go --sequencer examples/sequencer_1.yaml --record output.wav

Register virtual midi device

go run main.go --midi

Change instruments banks for virtual midi device

go run main.go --instruments examples/bank.yaml --percussion examples/percussion_bank.yaml --midi

Contributing

Contributions are always welcome, but if you want to introduce a breaking change please raise an issue first to discuss. For small additions and bug fixes feel free to just create a PR.

License

This package is licensed under a MIT License:

Copyright 2019-2020, Bart Spaans

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is furnished to do
so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.