AstroBar

A native macOS menu bar companion for the ASTRO A50 (Gen 4) wireless headset.
Battery, equalizer, mix and microphone — read and written straight over USB HID. No Logitech G HUB, no Astro Command Center, no background service.

Website • Overview • Install • The panel • Equalizer presets • Settings • Architecture • Development • Releasing

Overview

The A50 Gen 4 base station exposes everything over a vendor-defined USB HID interface — charge level, dock state, the full parametric equalizer, the mix sliders, the microphone. Astro Command Center could reach all of it, but it was discontinued and never ran on Apple silicon. G HUB does not cover the Gen 4.

AstroBar is that control panel, rebuilt as a Mac menu bar app. It talks to the base station directly through IOHIDManager — no root, no kext, no driver, no helper process.

The project stays deliberately:

• menu-bar-first — no main window, no Dock icon, no launch screen.
• local-first — nothing leaves the machine, no account, no telemetry.
• near dependency-free — Sparkle for in-app updates is the only external Swift package.
• honest about what it knows — an estimate is withheld until it has been measured, and a reading the base station only remembers is labelled as such.

Unofficial hobby project. Not affiliated with, endorsed by, or sponsored by Logitech or ASTRO Gaming — see Disclaimer.

Highlights

• Battery and power — ring gauge, optional percentage in the menu bar, and a low-battery notification with a configurable threshold.
• Estimated time — how long the charge will last, or how long it still needs to fill up. Learned from the observed rate, kept separately for discharging, charging on the base and charging in use, and remembered across restarts.
• Resolved power state — the hardware reports dock, radio link and charging as three separate bits; the panel shows one answer: In use, Charging, Charged, Off.
• Full parametric equalizer — three slots, each with per-band gain (±7 dB), centre frequency (80–15 000 Hz) and bandwidth. Rename slots inline.
• 15 loadable presets — the five originals from Astro Command Center plus ten from The ZEFERENCE, with JSON import. See Equalizer presets.
• Mix — game/chat balance and alert volume.
• Microphone — level, side tone, noise gate (Streaming / Night / Home / Tournament) and mic EQ.
• Stream output — the levels going to the base station's stream port, which is what an audience hears: Mic, Chat, Game, Aux.
• Automatic updates — signature-verified, through Sparkle.
• Diagnostic CLI — astrobar-cli speaks the same protocol from a terminal.

Requirements

• macOS 14 (Sonoma) or later
• An ASTRO A50 Gen 4 with its base station, connected by USB
• To build: Xcode 26 or a current Apple Swift 6.2 toolchain

Not supported: the A50 X / Gen 5 (2024+) speaks a completely different protocol from the Logitech G HUB family. Plugging a Gen 4 headset in by USB cable enumerates as a plain audio device (0x9886:0x002b) that charges but exposes no control interface at all.

Install

Prebuilt disk images live under Releases.

1. Download AstroBar-<version>.dmg and open it.
2. Drag AstroBar.app into Applications.
3. Clear the quarantine flag — see below.
4. Launch it. The icon appears in the menu bar; no window opens.

Gatekeeper on first launch

This project has no Apple Developer account, so the app is ad-hoc signed and not notarized. macOS blocks it the first time and claims it is damaged or from an unverified developer. That is expected and does not mean the download is broken.

xattr -dr com.apple.quarantine /Applications/AstroBar.app

Or open it once via System Settings → Privacy & Security → Open Anyway.

Locally built copies carry no quarantine flag and open normally.

From source

git clone https://github.com/nichtlegacy/AstroBar.git
cd AstroBar
make install        # builds, installs to /Applications and launches

The panel

Click the menu bar icon to open it, click again to close it — like any system menu. Escape closes it too, and expanded sections collapse again when it closes.

Everything except Save applies live. Save writes the current values into the headset so they survive a power cycle; the button turns green on success and red on failure, then goes back.

Section	What it does
Header	Charge ring, model, where the headset is, what it is doing, and the estimated time to empty or full
Equalizer	Pick the active slot, expand one to edit its five bands, rename it, or replace it from the preset library
Mix	Game/chat balance and alert volume
Microphone	Mic level, side tone, noise gate, mic EQ
Stream output	Collapsed by default — the levels your audience hears

Equalizer presets

The A50 has three writable EQ slots. AstroBar ships 15 tunings you can load into any of them from the menu next to the preset's name field. Loading one overwrites that slot's name, gains and all five bands — but only becomes permanent once you press Save, so you can audition freely and power-cycle the headset to get your originals back.

Astro Command Center

The five presets the discontinued Command Center shipped, recovered from a USB capture of it writing each preset to a slot.

Preset	Good for	What it does
ASTRO	Games, trailers	The house sound — a pronounced V: bass and treble up, mids scooped
PRO	Bass-heavy games	Bass lift plus a strong presence peak, mids pulled back
STUDIO	Critical listening	Flat through the low end, brightened on top
MEDIA	Music, video, voice chat	The gentlest of the five: a small dip where boominess lives, a modest lift for dialogue
A50 MOD KIT	Mod Kit cushions only	On stock cushions it corrects something that isn't there

The ZEFERENCE by ZaliaS

Ten presets from The ZEFERENCE, distributed as .astroeq files — the same format Command Center reads. All tuning work is ZaliaS's; AstroBar only converts the published values into the form the device expects.

Preset	Good for	What it does
RECTIFY4	A neutral baseline	The only preset written for this exact headset: flattens the A50 Gen 4's own colouration towards a studio reference
PURE	Music, film, games	Broad all-rounder, generous in the bass
DYSTRILATION	Instrumental music	Crisp mids and treble, detail first
INCENDIARY	Film, Plex, YouTube	Theatrical weight in the low and mid range
KRYOGEN	Mixed listening	The reverse of Incendiary — lows and treble, mids left neutral
ARCTURUS	Any game	Broad, weighty tuning meant to suit everything
OMNIVOX	Shooters, generally	Low/mid focus for audible footstep direction
TOURNAMENT I / II / III	Competitive FPS	Three takes on positional clarity — the author's advice is to try all three and keep whichever suits your game

Only presets that apply to an A50 Gen 4 are bundled. The collection's A40 and Gen 3 tunings target different hardware, and its per-game presets are too narrow for a menu bar app — get those from the source repository.

Which preset sounds best is a matter of taste and of your ears. These descriptions come from the authors and from the filter curves, not from measurements taken on your unit.

Import

Import from File… in the same menu reads a JSON preset file:

{
  "version": 1,
  "presets": [
    {
      "name": "MY PRESET",
      "gain": [0, -3, 0, 2, 4],
      "bands": [
        { "centerFreq": 95,   "bandwidth": 0 },
        { "centerFreq": 406,  "bandwidth": 8192 },
        { "centerFreq": 783,  "bandwidth": 8192 },
        { "centerFreq": 3901, "bandwidth": 6963 },
        { "centerFreq": 6339, "bandwidth": 0 }
      ]
    }
  ]
}

bandwidth is the figure Command Center shows (0.1–3.0) multiplied by 4096. The outer two bands are shelves and carry no width. Presets without exactly five bands are skipped, and a file with none left is rejected rather than partially written to the hardware.

Settings

Open Settings from the gear in the panel footer, the status item's right-click menu, or ⌘,. It always opens on General.

Pane	What you can do
General	Launch AstroBar at login
Menu Bar	Show the battery percentage next to the icon, and choose between a headphone or a battery-level icon
Notifications	Turn the low-battery alert on and pick its threshold (5–50 %)
Device	Connection state, USB id, base and headset firmware versions, auto-shutoff timer
About	Version, links, and the update controls below

Updates

Installed copies keep themselves current through Sparkle. AstroBar checks the appcast in this repository, and every download is verified against an EdDSA signature before it is installed. That check does not involve Apple, so it still means something even though the build is not notarized: an update can only come from whoever holds the private key.

In Settings → About → Updates:

• Check for updates automatically — look for new releases in the background and ask before installing anything. Nothing is ever installed silently.
• Download updates in the background — fetch releases ahead of time so they're ready to install. Only available while automatic checks are on.
• Last checked — when the feed was last read.
• Check for Updates… — a manual check that shows Sparkle's window even when you are already up to date.

The same manual check sits in the status item's right-click menu and in the app menu. Updates stay idle in debug builds and whenever the bundle carries no feed URL, which is the case under swift run.

Architecture

flowchart TB
    subgraph hw["Hardware"]
        BASE["A50 Gen 4 base station<br/>USB 0x9886:0x002c"]
    end

    subgraph core["AstroBarCore — no UI, unit tested"]
        TRANSPORT["HIDTransport<br/>IOHIDManager on its own run loop"]
        FRAME["A50Frame<br/>encode / parse / decode errors"]
        DEVICE["A50Device (actor)<br/>typed commands, one request in flight"]
    end

    subgraph app["AstroBar — the app"]
        MONITOR["A50Monitor<br/>@Observable source of truth"]
        EST["BatteryEstimator<br/>rate per profile"]
        PANEL["MenuPanelView<br/>SwiftUI in an NSPanel"]
        SETTINGS["Settings window"]
        STATUS["NSStatusItem"]
    end

    DEFAULTS[("UserDefaults<br/>learned rates, prefs")]
    APPCAST["appcast.xml<br/>EdDSA signed"]

    BASE <-->|"64-byte HID reports"| TRANSPORT
    TRANSPORT <--> FRAME
    FRAME <--> DEVICE
    DEVICE -->|"poll every 8s"| MONITOR
    MONITOR -->|"writes on commit"| DEVICE
    MONITOR --> EST
    EST <--> DEFAULTS
    MONITOR --> PANEL
    MONITOR --> STATUS
    MONITOR --> SETTINGS
    APPCAST -.->|"Sparkle"| app

Loading

The wire protocol

The control interface is a vendor-defined HID endpoint (usage page 0xFF32) carrying fixed 64-byte reports. It was reverse-engineered by tdryer/eh-fifty:

• Request: [0x02, command, (length, …payload)]
• Response: [0x02, status, length, …data] — 0x02 is OK, 0x01 is an error

Error replies carry a little-endian code and a NUL-terminated ASCII name four bytes into the payload, which AstroBar surfaces verbatim:

02 01 24 0d 00 00 00 48 49 44 5f ...
..$....HID_ERROR_NO_EQ_WITH_THAT_VALUE

Three firmware behaviours the code works around, all confirmed against hardware:

• The declared reply length is unreliable in both directions — the firmware pads and under-reports — so callers state how many bytes they need.
• Applying an EQ preset is asynchronous: the write is acknowledged before it takes effect, so the setter polls the read-back.
• Bit 1 of 0x54 is the radio link, not simply "powered on". The base keeps answering with the last known battery level after the link drops, so those readings are marked stale and kept out of the estimator and the alert.

Packages

Package	Kind	Purpose
AstroBarCore	library	HID transport, wire protocol, models, request codec. No UI.
AstroBar	app	SwiftUI content inside an AppKit menu bar shell.
astrobar-cli	executable	Diagnostic dump of every value the device exposes.

Diagnostics

astrobar-cli speaks the same protocol from a terminal — useful for bug reports:

swift run astrobar-cli dump             # read-only dump of every value
swift run astrobar-cli get-eq           # print the active EQ preset
swift run astrobar-cli set-eq 2         # set the active EQ preset (writes!)
swift run astrobar-cli selftest-write   # toggle EQ preset and restore it (writes!)
swift run astrobar-cli probe-error      # hex-dump the device's error frames

Development

swift build && swift test          # no hardware required
./scripts/package_app.sh release   # assemble AstroBar.app
make dmg                           # distributable disk image
make icon                          # regenerate the app icon

Unit and render tests run without a device; only live reads and writes need hardware. See CONTRIBUTING.md for code style and PR guidelines.

Releasing

Releases are cut locally, not from CI: signing the appcast needs the private EdDSA key, which lives in the login keychain and never leaves the machine.

scripts/release.sh --version 1.0.0 --dry-run   # rehearse, publishes nothing
scripts/release.sh --version 1.0.0             # build, tag, publish, update appcast

The script refuses to run on a dirty worktree or off main, verifies the key is reachable before it tags anything, and asks for confirmation before publishing. Release notes come from .github/release-notes/<version>.md when present, otherwise from the commit log.

Back up the signing key. Without an Apple Developer account this key is the only thing proving an update came from you. Lose it and every installed copy stops accepting updates; leak it and anyone can ship an update to every installed copy.

scripts/backup_sparkle_key.sh ~/somewhere-encrypted/astrobar-sparkle-key.txt

Acknowledgments

AstroBar stands on work other people did first.

• tdryer/eh-fifty — the original reverse engineering of the Gen 4 HID protocol. Every command byte this app sends was documented there first.
• ZaliaS — The ZEFERENCE — the ten bundled community EQ presets (RECTIFY4, PURE, DYSTRILATION, INCENDIARY, KRYOGEN, ARCTURUS, OMNIVOX and the Tournament series). All tuning work is theirs. The full collection, including A40, Gen 3 and per-game presets, lives in the source repository.
• manuacl/astro-a50-gui — recovered the five original Astro Command Center presets from a USB capture.
• Sapd/HeadsetControl — protocol notes that corrected real bugs here, in particular that the base station keeps serving the last known battery level after the headset drops off the radio link.
• Sparkle — in-app updates.
• App architecture inspired by steipete/CodexBar.

License

MIT. Do what you like with it.

Disclaimer

AstroBar is an unofficial, independent hobby project. It is not affiliated with, endorsed by, sponsored by, or connected to Logitech or ASTRO Gaming in any way.

I have simply been a big fan of the A50 for years and use it every day. When Astro Command Center was discontinued and never made it to Apple silicon, the headset kept working but lost its control panel on the Mac. This app exists to give it one back.

"ASTRO", "A50" and related marks are trademarks of their respective owners and are used here only to describe which hardware this app talks to.