scapectl

Native desktop controller and CLI for the Fractal Design Scape wireless gaming headset.

Features:

• Real-time headset connection/disconnection detection
• Realtime status of headset features (battery level, status of mic, mute, RGB, noise cancellation, sidetone)
• Trigger scripts on headset power on/off and 2.4GHz receiver connect/disconnect (e.g. switch audio output)
• Send commands: switch EQ preset, toggle RGB on/off, toggle mic noise cancellation

Planned, not yet implemented:

• Customize headset button controls
• EQ code import/export
• Full lighting theme control
• Detect when connected via Bluetooth

Built for macOS, Windows and Linux, but so far only tested on macOS and Windows.

• Install
• Security and Privacy
• Usage
• Configuration
• Triggers
• Building from source
• Credits
• License
• USB HID Protocol Reference

This is an unofficial app made for my own purposes, freely shared without any guarantees. I am not affiliated with or endorsed by Fractal Design in any way. The USB communication protocol was observed and documented from Fractal's Adjust Pro web app.

Install

Prebuilt downloads

Grab the latest release for your platform from the Releases page. If you wish to compile yourself, see Building from source

Homebrew (macOS)

brew tap charlietran/scapectl https://github.com/charlietran/scapectl
brew install --cask scapectl

Installs /Applications/ScapeCtl.app and symlinks the scapectl CLI onto your Homebrew path. The cask's postflight strips quarantine attributes and re-signs the app locally, so you can skip the manual xattr step in Security and Privacy.

To uninstall (the --zap flag also removes config files in ~/Library/Application Support/scapectl):

brew uninstall --cask --zap scapectl

Security and Privacy

This app is not macOS notarized and not Windows signed. Your OS will flag it as untrusted on first run. If this raises one or both of your eyebrows, it should! Stop running random programs from strangers on the internet! But this is a hobby project and I'm not going to bother paying for Apple and Microsoft developer accounts.

This app does not contain any telemetry or otherwise make network calls in the background. It does make a network request to check for the latest version if you click on the "Check for update" menu item.

macOS

macOS will block the app with "ScapeCtl is damaged and can't be opened" or "cannot be opened because the developer cannot be verified". If you installed via Homebrew, the cask handles this automatically. Otherwise, remove the quarantine attribute manually:

xattr -cr ScapeCtl.app

macOS also requires explicit permission for the app to read USB data from the headphones. On first run you may see a "not permitted" error. Go to System Settings → Privacy & Security → Input Monitoring, click +, add the ScapeCtl app, and toggle it on.

Windows

Windows will show a "Windows protected your PC" SmartScreen warning. Click More info → Run anyway.

Linux

A udev Required for non-root HID access:

make udev
# OR manually:
sudo cp 50-fractal.rules /etc/udev/rules.d/
sudo udevadm control --reload-rules && sudo udevadm trigger

Usage

The app is meant to be simple menu interface for seeing the status of the headphones and easily toggling some of its features. You may also configure it to run scripts upon certain events, to automate things like switching the audio device when the headphones are docked and undocked.

Important

scapectl cannot be used at the same time as Fractal's Adjust Pro web app. Both talk to the dongle over the same USB HID stream and will fight over responses, leaving both in an inconsistent state. Close the Adjust Pro tab (and quit its offline Electron app if you have it) before launching scapectl, and likewise close scapectl first if you need to use the Adjust Pro web app.

Configuration

Config file location:

• macOS: ~/Library/Application Support/scapectl/config.toml
• Linux: ~/.config/scapectl/config.toml

A default config with comments is created on first run. See config.example.toml for all options.

Triggers

Run scripts automatically on device events. Enable "Trigger Scripts" in the menu, and add [[triggers]] entries to your config file (see config.example.toml for all options).

Notifications

macOS:

[[triggers]]
event   = "HeadsetPowerOn"
script  = "osascript -e 'display notification \"Headset connected\" with title \"Scape\"'"
enabled = true

[[triggers]]
event   = "HeadsetPowerOff"
script  = "osascript -e 'display notification \"Headset disconnected\" with title \"Scape\"'"
enabled = true

Windows — uses notify.ps1, a small PowerShell script shipped alongside scapectl.exe:

[[triggers]]
event   = "HeadsetPowerOn"
script  = 'powershell -ExecutionPolicy Bypass -File "%SCAPE_DIR%\notify.ps1" -Message "Headset connected"'
enabled = true

[[triggers]]
event   = "HeadsetPowerOff"
script  = 'powershell -ExecutionPolicy Bypass -File "%SCAPE_DIR%\notify.ps1" -Message "Headset disconnected"'
enabled = true

Audio Switching

The app cannot switch audio devices for you, but the trigger functiona allows you to execute any script you like. Here are config examples for how to automatically switch your default audio output when the headset powers on/off, with separate command-line audio switching tools:

Note: Trigger scripts run without a login shell, so tools may not be on PATH. Use the full path to the executable in your trigger scripts. Run which SwitchAudioSource (macOS) or where nircmd (Windows) to find it.

macOS — install SwitchAudioSource:

brew install switchaudio-osx
which SwitchAudioSource  # e.g. /opt/homebrew/bin/SwitchAudioSource
SwitchAudioSource -a     # list available devices

Note

The full path to SwitchAudioSource may differ on your system, run which SwitchAudioSource to see your actual path

[[triggers]]
event    = "HeadsetPowerOn"
script   = "/opt/homebrew/bin/SwitchAudioSource -s 'Fractal Design Scape'"
enabled  = true
cooldown = 5

[[triggers]]
event    = "HeadsetPowerOff"
script   = "/opt/homebrew/bin/SwitchAudioSource -s 'MacBook Pro Speakers'"
enabled  = true
cooldown = 5

Windows — download NirCmd (free, single .exe, no install required). Place it somewhere permanent and use the full path:

Note

Replace C:\Tools\nircmd.exe below with the actual location of where you put nircmd.exe

[[triggers]]
event    = "HeadsetPowerOn"
script   = 'C:\Tools\nircmd.exe setdefaultsounddevice "Fractal Design Scape" 1'
enabled  = true
cooldown = 5

[[triggers]]
event    = "HeadsetPowerOff"
script   = 'C:\Tools\nircmd.exe setdefaultsounddevice "Speakers" 1'
enabled  = true
cooldown = 5

Linux — uses pactl (PulseAudio) or wpctl (PipeWire), usually pre-installed:

pactl list short sinks   # list devices (PulseAudio)
wpctl status             # list devices (PipeWire)

[[triggers]]
event    = "HeadsetPowerOn"
script   = "pactl set-default-sink alsa_output.usb-Fractal_Design_Scape"
enabled  = true
cooldown = 5

[[triggers]]
event    = "HeadsetPowerOff"
script   = "pactl set-default-sink alsa_output.pci-0000_00_1f.3.analog-stereo"
enabled  = true
cooldown = 5

Replace device names in the examples above with your actual device names.

Trigger fields

Field	Required	Description
event	Yes	Event name (see table below)
script	Yes	Shell command to run
enabled	Yes	true or false
cooldown	No	Minimum seconds between firings (default: 0). Prevents the same script from running repeatedly if the event fires in quick succession.
battery	No	For BatteryLevel only: fire when battery <= this % (default: 20)

Available events

Event	Description
DongleConnected	USB receiver plugged in
DongleDisconnected	USB receiver unplugged
HeadsetPowerOn	Headset turned on (detected via dongle)
HeadsetPowerOff	Headset turned off or out of range
BatteryLevel	Battery update (use battery field for threshold)
MicMuted	Mic muted (boom flipped up)
MicUnmuted	Mic unmuted (boom flipped down)
EqChanged	EQ preset slot changed
RgbOn	RGB lighting turned on
RgbOff	RGB lighting turned off
MncOn	Mic Noise Cancellation enabled
MncOff	Mic Noise Cancellation disabled

Environment variables

Scripts receive these environment variables:

Variable	Example
SCAPE_EVENT	HeadsetPowerOn
SCAPE_DEVICE	Fractal Scape Dongle
SCAPE_VID	36bc
SCAPE_PID	0001
SCAPE_PATH	DevSrvsID:4295080900
SCAPE_TIMESTAMP	2026-03-21T14:30:00-07:00
SCAPE_JSON	Full event as JSON
SCAPE_BATTERY	Battery % (BatteryLevel events only)
SCAPE_DIR	Directory containing the scapectl executable

CLI

You may optionally use the CLI for your own scripting or tinkering. Running scapectl with no arguments launches the system tray app. Pass a subcommand for CLI mode:

scapectl status       # Print battery, firmware, EQ slot, mic, connection info
scapectl devices      # List connected Fractal HID devices
scapectl sniff        # Continuously print incoming HID data
scapectl raw 02 f1 21 # Send arbitrary HID bytes

On macOS, the binary is inside the app bundle. You can run CLI commands from it directly:

ScapeCtl.app/Contents/MacOS/scapectl status

On Windows and Linux, run the binary directly:

# Windows
scapectl.exe status

# Linux
./scapectl status

Building from source

git clone https://github.com/charlietran/scapectl
cd scapectl
make build
./scapectl

Requires Go 1.22+. No other system dependencies on any platform.

Cross-compilation

All builds are pure Go (no CGO). You can cross-compile for all 3 platforms from any of them.

Credits

• USB HID implementation based on rafaelmartins/usbhid — pure Go USB HID via native OS APIs (IOKit, hidraw, WinAPI). BSD-3-Clause.
• System tray via fyne-io/systray — cross-platform system tray library. BSD-3-Clause.
• ebitengine/purego — pure Go syscall bridge for calling C libraries without CGO. Apache-2.0.
• Claude Code - huge help with figuring out the USB protocol and implementing the cross-platform Golang app

License

GNU General Public License v3.0

---

USB HID Protocol Reference

This section is a reference for anyone who wants to interact with the Fractal Scape headset via USB. Reverse-engineered from WebHID sniffer captures and the Fractal Adjust Pro Electron app source.

Reverse Engineering Tools

• tools/webhid_sniffer.js — Paste into Chrome DevTools on adjust.fractal-design.com to capture all HID traffic with annotations

Device Identifiers

Device	VID	PID	Notes
Fractal Scape Dongle	0x36BC	0x0001	2.4 GHz USB wireless receiver
Fractal Scape (wired)	0x36BC	TBD	USB-C direct connection
Adjust Pro Hub	0x36BC	0x1001	Fan/RGB controller (different product)

HID Transport

• Report ID: 2 (all commands use report ID 2)
• Payload size: 63 bytes (report ID excluded)
• Transport: Output reports (sendReport, not feature reports)
• Collection: usagePage 0xFF00, usage 1 (vendor-specific, collection index 3)
• Response pattern: all responses echo the first 2 command bytes

The dongle exposes 4 HID collections. Only collection 3 (usagePage 0xFF00) is used for the control protocol. The others are Consumer Control (media keys), vendor 0xFF13 (unknown), and Telephony (call buttons). On macOS, the IOHIDManager must be opened with a matching dictionary restricted to the Fractal vendor ID to avoid triggering the Input Monitoring permission prompt (the Consumer Control collection looks like a keyboard to macOS).

Architecture: Dongle vs Headset

The dongle acts as a wireless relay. Commands prefixed 0x11 are handled by the dongle directly (instant response). Commands prefixed 0xF1 are relayed to the headset (slower, ~60ms round-trip when online, times out when headset is off).

The Adjust Pro web app treats these as two separate "devices" internally:

• Dongle controller (DEVICE_TYPE_FACTORY_DONGLE = 0x11): queries dongle state
• Headset delegate (DEVICE_TYPE_FACTORY_HEADSET = 0xF1): queries headset status, controls EQ/mic/lighting

Command Reference

0x11 — Dongle Commands

Command	Description	Response
11 01	Dongle firmware version	11 01 00 <major> <minor>
11 02	Dongle serial number	11 02 00 <ASCII string, null-terminated>
11 21	Dongle state poll	11 21 00 <headset_present> ...

Note: 11 21 byte 3 (headset_present) is unreliable — it flaps in a cycle tied to the dongle's 2.4 GHz radio polling. Do not use it for presence detection. Use f1 21 byte 18 instead.

0xF1 — Headset Commands

Command	Description	Response
f1 01	Headset firmware version	f1 01 00 <major> <minor>
f1 02	Headset serial number	f1 02 00 <ASCII string, null-terminated>
f1 05	Headset info	f1 05 <data...>
f1 21	Full status poll	63-byte status blob (see below)
f1 34 XX YY	Sidetone control	XX=action, YY=steps (see below)
f1 36 01	Enable MNC	Mic Noise Cancellation on
f1 36 00	Disable MNC	Mic Noise Cancellation off

Sidetone (f1 34):

Action byte	Meaning
0x00	Disable
0x01	Enable
0x02	Vol up
0x03	Vol down

Volume is relative (step-based), max 75 steps. Values >50 must be split across multiple commands. A status poll (f1 21) must be sent between each f1 34 command — without it, the dongle acknowledges locally but does not relay to the headset.

f1 21 Status Blob:

Byte	Field	Values
0-1	Echo	f1 21
2	Status	0 = OK
3	Boom mic	0 = detached, nonzero = attached
4	Muted	0 = unmuted, nonzero = muted
5	EQ slot	1-3
6	Lighting slot	0 = off, 1+ = active
7-8	Chat volume
9-10	Game volume
11	Volume state
12	BT mode
13	Hall sensor	Boom mic position sensor
14	Battery	0-100 (%)
15	Sidetone state	1 = on
16-17	Sidetone vol
18	BT connection	1 = connected (reliable for presence)
19	MNC (ENC)	1 = on
20	Power state	1 = on
33	Dynamic lighting
40	WDL opt-in	Windows Dynamic Lighting

Note on byte 3/4: The Electron app source labels these as hasBoomMic and isMuted with inverted semantics (0 = attached, 0 = muted). In practice the actual device behavior matches the table above. The code handles this correctly — test with your device if in doubt.

0xA4 — Config Transfer & Lighting

Command	Description
a4 01 01 NN SS CC	Begin config write (length, segments)
a4 02 3c <60 bytes>	Config data chunk (0x3c = 60 bytes)
a4 03	End config write
a4 04 00	Select effect slot 0 (RGB off)
a4 04 01	Select effect slot 1 (RGB on)
a4 05 01 00 00	Read current config/state
a4 0e 99	Keepalive heartbeat

Lighting themes are uploaded as bulk data via a4 01/a4 02/a4 03. Simple on/off uses a4 04.

0xA5 — Lighting Brightness/Color Upload

Command	Description
a5 f0 00 ff	Begin brightness/color upload
a5 01 00 ff <data>	Data chunk
a5 f1 00 ff	End upload

0xA7 — DSP / Audio (EQ)

Command	Description
a7 01 XX 01 YY	Init DSP slot (XX: 0x17/0x27/0x37 for driver 1/2/3)
a7 02 NN DD PP <5×f32>	Set biquad coefficients (LE float32)
a7 03 DD 02 00 <UUID>	Set driver config with preset UUID
a7 04 DD 00/01	Enable/disable feature per driver
a7 05 NN DD PP	Set parameter per driver/band
a7 07 DD	Select EQ slot / apply driver config

EQ Architecture:

• 3 preset slots, each with up to 5 parametric EQ bands
• Each band: frequency (Hz), Q factor, gain (dB), filter type
• Filter types: 0 = peaking, 1 = low shelf, 2 = high shelf
• Biquad coefficients (IIR second-order sections) are pre-computed per sampling rate
• Driver IDs: 1, 2, 4 (corresponding to different audio paths/sample rates)
• Coefficients per band: EqCoefA = [a1, a2], EqCoefB = [b0, b1, b2]
• Switching EQ slots re-uploads all coefficients — a7 07 <slot> selects which slot is active

EQ Code Format (shareable preset strings from the web app):

• Base64-encoded binary: [version=1][numPoints][15 bytes per band][XOR checksum]
• Per band (15 bytes): [filterType:u8][gain:f32 LE][Q:f32 LE][freq:u16 LE][4 bytes padding]
• Checksum: XOR of all preceding bytes

Polling & Connection Detection

scapectl keeps a persistent HID connection to the dongle and polls f1 21 every 1.5s with a 500ms timeout. It also sends a4 0e 99 keepalive after each successful status poll.

Connection detection uses f1 21 byte 18 (btConnState) exclusively:

• Headset online: f1 21 returns within ~60ms, byte 18 = 1
• Headset offline: f1 21 times out (500ms) — returned as disconnected status, not an error
• Dongle unplugged: HID I/O error closes the connection; next tick re-enumerates the USB bus

The dongle also sends unsolicited 11 21 reports. The SendAndReceive function filters by echo bytes (first 2 bytes of the response) to match the correct reply, discarding any unsolicited reports.

Why not use 11 21 for presence? The Adjust Pro web app uses 11 21 byte 3 as a fast presence check before creating a headset delegate. But byte 3 is unreliable — it flaps tied to the dongle's 2.4 GHz radio polling cycle. scapectl skips 11 21 entirely and relies on f1 21 byte 18. The tradeoff is slightly slower disconnect detection (~5s for the dongle's internal relay timeout vs instant) but zero false positives.