brettbuddin / Shaden

Shaden

Shaden is a modular audio synthesizer. Patches for the synthesizer are written in a Lisp dialect. A REPL and HTTP interface are provided for interacting with the synthesizer in real-time. I started this project as a way of learning more about digital signal processing and music theory. Consider this an art project.

The name "shaden" comes from the Cycle of Galand book series by Edward W. Robertson.

Highlights

• Lisp interpreter for creating patches
• Large collection of builtin Units
• Music theory primitives
• MIDI controller and clock input
• Single-sample feedback loops
• Editor plugins for sending expressions to the synth for evaluation:
  • Vim
  • VS Code

Dependencies

• Go 1.9+
• PortAudio
• PortMIDI

On macOS you can install these dependencies with: brew install go portaudio portmidi

Getting Started

Install

$ go get -u github.com/brettbuddin/shaden

CLI Usage

REPL

$ shaden -repl
> (define gen (unit/gen))
> (-> gen (table :freq (hz 300)))
> (emit (<- gen :sine))

Load File

$ shaden examples/frequency-modulation.lisp

HTTP

$ shaden examples/krell.lisp
$ curl -X POST http://127.0.0.1:5000/eval -d "(=> rise (table :x (ms 100))) ; ..."

This is my preferred way of interacting with the synthesizer. I've written a small Vim plugin that can send over snippets of Lisp code to the program for evaluation. You can find that plugin here.

The HTTP interface is limited to Lisp evaluation at the moment, but I have hopes of providing an API for direct graph manipulation via HTTP.

Lisp

For a more information about the Lisp dialect bundled with Shaden, check out the wiki.

Examples

The best way to get to know the way patching works in Shaden is to look at the examples directory.

I gave a lightning talk at GopherCon 2018 about Shaden:

Shaden was used to create the intro music for the GothamGo 2017 and GothamGo 2018 conference videos. I frequently post patches I've created on Instagram.