KB1 is a compact MIDI keyboard controller built specifically for the Polyend Tracker Mini. It is configured via a browser-based web app connected via Bluetooth Low Energy.
Hardware
- 19-key keyboard
- 2 levers with integrated push buttons
- 1 capacitive touch input
- 2× 8Ω 1W speakers
- XIAO ESP32-S3 MCU with BLE and USB-C
- 420mAh Li-ion battery, charged via USB-C
Firmware (details)
- Lever, press, and touch controls: configurable CC output and parameter-specific behavior
- Scale mode: note output quantized to a selectable musical scale
- Chord mode: selectable chord types, Block/Strum playback, and 1–3 octave range
- Arp Mode: User defined arpeggiator
- 8 on-device preset slots
- Serial MIDI output
Web Configuration App (details)
- Mobile first design
- Runs in Chromium based browsers (iOS: Safari does not support Web Bluetooth. V Browser recommended for iOS)
- Connects over Web Bluetooth
- Settings load from and save to device over BLE
- 12-slider live performance interface (landscape fullscreen on mobile)
- Preset management stored in browser
- KB1 Studio User Guide and Tools: Hardware setup, charging, Tracker configuration, firmware updates, and instrument building.
- Configurator User Guide: Current app settings, presets, and performance sliders.
- Firmware README: Development builds and complete release images.
- Hardware Design and Assembly: Electronic and mechanical files.
- Contributing: Shared conventions, documentation ownership, and release validation.
Each repository README covers its own setup. Detailed user instructions live in the guides above rather than repeated copies.
- Firmware build and upload; use the complete-image builder for distributable firmware.
- Configurator development.
- Studio development.
- Software & Firmware: MIT License (see LICENSE)
- Hardware Designs: CERN Open Hardware Licence v2 – Strongly Reciprocal (see hardware license)