Glacier EQ

Cross-platform parametric EQ editor for compatible USB DACs. Glacier EQ talks to hardware over HID, edits EQ locally, and works offline.

⚡ Try the web version directly in your browser: bukutsu.github.io/glacier-eq

Features

• 10-band PEQ editor with preamp, undo/redo, graph preview, and target curves
• Pull, RAM-apply, push, verify, and rollback EQ on supported DACs
• Local profiles with search, import/export, copy/paste, and one-tap apply
• Measurement overlays from files or optional Squiglink offline cache
• Native AutoEQ matching against measurement and target curves
• Walkplay/Savitech, Moondrop, and FiiO EQ protocol support
• Hardware controls for supported Walkplay/Savitech DACs: DAC filter, amp mode, output gain, balance, mic monitor, and reset modes
• Desktop and Android layouts, themes, diagnostics, and dev dummy DAC

Install

Download builds from the releases page.

Arch Linux:

git clone https://github.com/Bukutsu/glacier-eq.git
cd glacier-eq
makepkg -si

The Arch package installs udev/99-glacier-eq.rules; after replugging a supported DAC, the Linux desktop build can open it directly without the polkit elevation popup.

From source:

git clone https://github.com/Bukutsu/glacier-eq.git
cd glacier-eq
npm install
npm run tauri dev

CLI

Glacier EQ includes a fully offline CLI for scripting, piping profiles, and bulk AutoEQ tasks. Data goes to stdout, diagnostics to stderr.

For the full command reference, syntax, and examples, see the CLI Documentation.

GUI Usage

1. Plug in a supported DAC.
2. Open Glacier EQ.
3. Select the DAC and connect.
4. Pull the current hardware state.
5. Edit preamp, bands, filter type, frequency, gain, and Q.
6. Push changes back to the device.

Supported Devices

If your DAC appears here, plug it in and check the device picker. Family match means the USB family looks compatible, but the exact model still needs more hardware reports.

Status	Device
Confirmed	EPZ TP35 Pro
Confirmed	TRN Black Pearl
Family match	Audiocular Aura
Family match	Fosi Audio DS2 / iBasso DC04 Pro
Family match	JCally JM20 / Savitech Generic
Family match	JCally JM20 Pro / Alt Savitech
Testing	Moondrop Dawn Pro
Testing	Moondrop Dawn Pro 2
Testing	FiiO JA11
Testing	JCally JM12
Testing	FiiO KA Series
Testing	Truthear KEYX

The app uses one registry for discovery, validation, capabilities, and the chooser list: glacier-core/src/device/walkplay.rs.

Development

Requirements:

• Node.js and npm
• Rust
• Tauri v2 platform dependencies
• USB/HID permissions for real hardware testing

Useful commands:

npm run dev              # frontend only
npm run tauri dev        # desktop app
npm run build            # TypeScript + Vite
cargo check              # Rust workspace
cargo test -p glacier-core

Optional local guard before pushing:

git config core.hooksPath .githooks

Android:

npm run android:doctor
npm run android:init
npm run android:dev
npm run android:apk

Release APK signing is not configured by default.

Roadmap

• Real-time frequency response graph
• AutoEQ matching
• Desktop and Android builds
• More DAC families beyond Walkplay/Savitech
• Interactive filter adjustment from the graph
• Full-screen Android filter adjustment
• Command-line profile tools
• Multi-device support
• Localization

Linux HID Permissions

On Linux, Chromium-based browsers and the desktop build can need udev access to raw USB HID devices. Installing the packaged udev/99-glacier-eq.rules lets the desktop build skip the polkit elevation popup. If you see a NotAllowedError: Failed to open the device error when connecting in the browser:

1. Create a udev rule file:

   sudo nano /etc/udev/rules.d/50-glacier-dac.rules

2. Paste the following rule to allow access to compatible DACs:

   # Walkplay / FiiO / Moondrop / EPZ DACs
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="3302", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="262a", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="2fc6", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="2972", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="0661", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="0666", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="35d8", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="31b2", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   KERNEL=="hidraw*", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="0d8c", MODE="0666", TAG+="uaccess", TAG+="udev-acl"
   

3. Reload udev rules and replug the device:

   sudo udevadm control --reload-rules
   sudo udevadm trigger

   Note: If you use the Chromium Flatpak or Snap version, you might also need to allow USB access in your sandbox permissions manager (e.g. Flatseal).

Project Layout

glacier-core/       Rust EQ and device logic
src/                React frontend
src-tauri/          Tauri backend
tauri-plugin-hid/   Local HID plugin
scripts/            Helper scripts

Credits

• Tauri
• React
• hidapi
• devicePEQ
• AutoEQ-C
• Audiocular-Aura, used as a reference for Moondrop and FiiO HID protocol behavior

License

GPL-3.0-only. See LICENSE.