Dhd

DHD — Dial Hifi Device

A physical motorized fader for seamless computer volume control.

Documentation · Assembly Guide · STL Files

Move the fader by hand to adjust volume. Change volume from your computer and watch the fader glide to match. Bidirectional, seamless, satisfying.

The DHD uses a Bourns PSL60 motorized fader with a PID-controlled DC motor, driven by a Raspberry Pi Pico 2 and a DRV8833 motor driver. The host daemon on Linux integrates with PulseAudio/PipeWire for system volume control.

The enclosure is designed as a GEN2 drawer — it slides directly into the GEN2 modular system with no custom fixation needed.

Features

• Bidirectional control — physical fader ↔ software volume, always in sync
• Auto-calibration — PID controller tunes itself to your hardware
• GEN2 compatible — standard drawer form factor, mounts in seconds
• Plug and play — USB auto-discovery, no configuration needed
• Persistent — calibration saved to flash, survives reboots

Quick Start

See the full documentation for detailed assembly and installation instructions.

# Clone
git clone https://github.com/Xowap/dhd.git
cd dhd

# Flash firmware (hold BOOTSEL while plugging in Pico)
rustup target add thumbv8m.main-none-eabihf
cd firmware && cargo run --release && cd ..

# Install host daemon
cd host && cargo run --release -- install && cd ..

Project Structure

dhd/
├── common/      # Shared library — protocol + PID controller (no_std)
├── firmware/    # Embassy async firmware for RP2350
├── host/        # Linux host daemon (Tokio + PulseAudio + systray)
├── simulator/   # TUI PID simulator for tuning without hardware
├── hardware/
│   ├── kicad/   # PCB schematics
│   └── stl/     # 3D printable parts
└── doc/         # Documentation source (Zensical)

Documentation

The full documentation is published at offworld-nexus-dhd.surge.sh and covers:

• Assembly instructions (BOM, PCB, 3D printing, step-by-step)
• Host software reference (installation, usage, protocol)
• Internals (PID control, motor driver, wiring)

License

This project is open source. Hardware (KiCad + STL), firmware, and host software are all available in this repository.