🍓Fraize

An opinionated multitrack phrase/loop sampler, written in Rust, with live performance in mind.

What

This is a mostly failed experimental project aiming to create a (time-synced) multitrack loop player/mangler.

The basic idea is you can load folders of audio loop files and use it as a kind of Live for the poor that can run on your Raspberry PI, Mac OSX, Linux + everything it can compile for.

Layout, goals:

• Tracks are linked to folders containing samples (one Track / one Folder).
• Each Track have a dedicated and configurable Sampler Engine (SampleGen).
• A SampleGen is basically a way to play a loop in sync with a clock according to a method.
  • think Timestretch / Beat Slicer / Re-Pitch ... or any other way to sync a bunch of samples with a tick.
• Each SampleGen implements its own way to mangle samples for fun (beat repeats, freeze, pitch shifts ...).
• Each Track can have a chain of FXs on top ( Filters / Delays / Reverbs ...).
• All this machinery is configurable with just a TOML file.
• All Tracks are synced to a MIDI Clock, Internal Clock, Ableton Link or even CV Clock ...

It runs headless

UI should be a separate project.

The sampler will run somewhere on the network and can be controlled by the UI via OSC API.

Features

• Onset / BPM analysis
• Slicer sample player
• Phase Vocoder sample player (basic timestretch, dirty)
• RePitch sample player (simple linear interpolation)
• MIDI Controls (CC)
• MIDI Clock (Virtual Midi Device)
• OSC API (wip)
• Config (see src/config/default.toml)

How it works ?

Samples

Each sample/loop present in the folders is loaded in memory then analysed for BPM detection / Beat detection / Onsets detection.

You can ease the work by setting directly the bpm in the file name, as in amen_break_180bpm.wav.

For this purpose, the aubio library is used in a rust wrapper around the C API.

• lib aubio
• aubio rust bindings

why Rust ?

Rust is a very promising language for realtime audio because it provides:

• high level of abstraction, embrace software complexity with elegance and modernity.
• memory safety,
• speed, in C ballpark, + auto-vectorization, SIMD ...
• fantastic tooling, that you will absolutely love.
• bounded execution times, no nondeterministic garbage collector latency.
• compiler, rustc is a real pair programmer.
• community, just as brillant as helpful.

Roadmap

• Sane (no clicks / pops), synchronized audio engine for all SampleGen.
• Variations / Region detection in loaded audio samples bars.
• Implement FXs.
• Implement a proper Timestretch SampleGen.
• Get rid of C dependencies.
• Test on more platforms.
• Live preformance tests.