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PGB-1 Compact Open-Source Groovebox (Plastic) - Image 1

PGB-1 Compact Open-Source Groovebox (Plastic)

MicroDigitalPolyphonic

Imagine slipping a full-featured groovebox into your pocket that punches way above its credit-card size, letting you craft beats and melodies anywhere without compromise.

This plastic-bodied powerhouse measures just 100x66x15mm and runs on a rechargeable Li-ion battery via USB-C, with a built-in speaker and headphone output for instant playback. At its heart is an RP2040 dual-core processor paired with a Cirrus Logic WM8960 audio codec, driving 6 digital synth channels and 2 sampler channels—complete with onboard sampling from the internal mic or 3.5mm line-in, plus 8 per-channel LFOs and 4 master effects like reverb, overdrive, bitcrush, and filters. Sequencing shines with 16 tracks (internal synth, samples, or MIDI), 16 patterns of 16 steps each, song mode, chord sequencer, 16 arpeggiators, live effects, and ratcheting; tweak sounds via 30 tactile switches, 25 RGB LEDs, a 128x64 OLED screen, and capacitive touch strip—no knobs needed for its slim profile. MIDI in/out and a web interface for sample import keep it connected and expandable.

Early users on forums like Elektronauts praise its open-source flexibility—stock CircuitPython firmware invites deep customization—and the surprising depth for such a portable rig, though some note the button-only interface takes practice to master.

Released

2025

Status

In Production

Synthesizer
Format
Micro, Workstation
Type
Digital, Sample-based
Internal Battery
Yes
Voice
A/D
Digital
Polyphony
Polyphonic
Oscillators
0
Oscillator Type
Virtual Analog
Voices
8
Tracks
16
Filter
Yes
Envelopes
-
LFO
8
Effects
Reverb, Overdrive, Bitcrush, Filters
Expression
Aftertouch
No
Velocity
No
MPE
No
Additional
open-source, 6 synth channels + 2 sampler channels, 8 LFOs (per channel), chord sequencer, chord generator, touch strip, on-board mic, web interface for sample import, plastic body, 128x64 OLED, USB-C rechargeable battery, portable
Software
-
I/O
Audio In
1x 3.5mm mono
Audio Out
1x 3.5mm stereo
Headphone
1x 3.5mm
MIDI
In, Out
MIDI Type
TRS (3.5mm)
Ports
USB-C
Wi-Fi
No
Workflow
Arpeggiator
Yes
Sequencer
Yes
Mod Matrix
No
Memory
16 patterns, 16 steps per pattern
Measurements
Dimensions
100 x 66 x 15 mm
Weight
-
Last updated Mar 25, 2026