Shadowbox

Open sourceMicro

Turn a Raspberry Pi running RNBO patches into a self-contained performance box with Shadowbox, Stretta's open-source runtime and hardware UI layer for standalone patch control.

Shadowbox is aimed at builders who want RNBO instruments away from the laptop. It auto-discovers RNBO runners and exposes patch browsing, parameter editing, preset management, and audio/MIDI routing from a compact physical interface built around an OLED display and rotary encoder. The project is distributed through GitHub for DIY use, making it a flexible starting point for custom Raspberry Pi instruments and installations.

Released

2026

Status

In Production

Product links

Github repo

Resources

Introducing Shadowbox

Synthesizer

Format

Micro, Experimental

Type

Digital

Battery Powered

DIY Option

Yes

Open source

Yes

Voice

A/D

Polyphony

Oscillators

Oscillator Type

Filter

Envelopes

LFO

Effects

Expression

Aftertouch

Velocity

MPE

Additional

Open-source Raspberry Pi runtime/control layer for RNBO patches with a compact hardware UI, OLED display, and rotary encoder. Auto-discovers RNBO runners and provides on-device patch, parameter, preset, audio, and MIDI controls.

Software

I/O

Audio In

Microphone input

Audio Out

Line out

Headphone

Headphone output

MIDI

MIDI Type

Ports

USB, MicroSD Card

Wi-Fi

Workflow

Arpeggiator

Sequencer

Mod Matrix

Memory

Measurements

Dimensions

Weight

Last updated May 2, 2026

Stretta

github.com

Stretta is the maker alias behind Shadowbox, an open-source Raspberry Pi runtime and hardware UI layer for Cycling '74 RNBO patches. The project turns a Pi into a standalone patch controller with OLED and encoder-based editing for patches, parameters, presets, audio, and MIDI routing.

Shadowbox

Product links

Resources

Specs