gb-z

gb-z turns the original Game Boy into a deep, playable groovebox. Program acid basslines and crunchy drums, sculpt every step, throw effects around live, and chain patterns into complete tracks.

Overview

Voices	4
Sequencer	16 steps · 16 patterns · two live projects
Effects	13 performance effects + sidechain
Performance	Live effects + live recording
Generative	Auto ∞ mode
Sync	MIDI clock and notes in/out + Game Boy link
Format	Standalone DMG-compatible .gb ROM

Build a track

1. Design the sound. Turn the pulse, wave and noise channels into synths, kicks, drum kits, samples and 303-style acid bass.
2. Program the details. Sequence notes across six editable lanes: duration, pitch, velocity, tables, command effects and trig conditions.
3. Create movement. Add polymeter, arpeggiators, LFOs and evolving pattern variation without losing the groove.
4. Turn patterns into a set. Arrange with song mode, sync to external gear over MIDI, or link another Game Boy.

303 patch

Try this starting point on the WAVE instrument, then add a few accents and slides to your bassline.

Voice	SHAPE saw, OCT +0
Filter	CUT 24, RES 23
Filter envelope	ENV 2/7, EDC 6/7
Accent and slide	ACC 7/7, SLD 3/7
Amp envelope (ADSR)	ATK 0, DEC 3, SUS 12, REL 0

ENV sets the filter envelope amount; EDC sets its decay. The separate ADSR controls the volume envelope.

Step components

A step in gb-z is more than a note. 

• Slides, accents, retriggers and octave jumps
• Conditional trigs such as 1:2, 3:4 and fill-only events
• Per-pattern polymeter for interlocking loops
• Tables for melodies, chord movement and evolving modulation

Auto ∞ mode

Switch on auto ∞ mode and gb-z writes an endless acid set that evolves bar by bar and never repeats. Let it run untouched, perform over it, or grab the controls and turn the machine’s idea into your own.

Made for hardware first

gb-z is a standalone, DMG-compatible Game Boy ROM for real hardware and emulators. It sounds AMAZING on real hardware.

Free Comic Book

rRead and learn how to compose on gb-z using the lovely bespoke made quick start guide