Stream Deck Lighting Control: Companion, MIDI, and Hotkey Setups for DMX

A Stream Deck can't send DMX by itself: it is a USB button panel that controls lights by triggering something that already speaks DMX, such as lighting software on a computer, Bitfocus Companion talking to a console or an Art-Net node, or a hardware controller with a MIDI input. Pick the route based on where your show is programmed.

What a Stream Deck does in a lighting rig

The signal chain always has a computer in it:

1. Stream Deck keys and dials
2. A host computer running the Stream Deck app or Companion
3. Lighting software or a console that holds your scenes, chases, and cues
4. A USB-DMX interface or Art-Net node
5. Your fixtures on the DMX line

The Stream Deck holds no show data. If the computer sleeps, crashes, or loses the USB connection, the keys stop doing anything, so treat the host as part of your lighting system and set it up with the same care as the DMX cable.

Size matters less than layout. A 15-key model is enough for one busking page: a few colors, a few positions, a strobe, and a safe look. The 32-key XL fits groups, colors, positions, and effects on a single page. Stream Deck + adds four dials, which suit group intensity and chase speed better than keys do.

Three ways to connect a Stream Deck to DMX lights

Method 1: keyboard shortcuts

This is the quickest way to try a Stream Deck with lighting software. In the Stream Deck app, drag a Hotkey action onto a key and record the shortcut your software uses for a scene, chase, or blackout. In QLC+, for example, each Virtual Console button can be given a keyboard combination in its properties.

The weak point is focus. Keystrokes go to whatever window is active, so a browser, a chat app, or a system dialog in front of the lighting software will catch them instead. Close other programs during the show and turn off notifications. Hotkeys are also on/off only; they can't send a fader level.

Method 2: MIDI into DMX software

MIDI is the most flexible free route, because most DMX software can learn MIDI messages. The steps below use QLC+, but the idea is the same in other programs.

1. Install a MIDI plugin for the Stream Deck app from the Stream Deck store.
2. Create a virtual MIDI port. On macOS, open Audio MIDI Setup, show the MIDI Studio, and set the IAC Driver to "Device is online." On Windows, a free virtual port tool such as loopMIDI does the same job.
3. Give each key a Note On message on that port. Use one MIDI channel and a different note for every key, and write the note map down.
4. In QLC+, open the Inputs/Outputs tab, pick a universe, and enable the virtual port as its input.
5. In the Virtual Console, open a button's properties, go to External Input, click Auto Detect, and press the Stream Deck key. Repeat for each button.
6. Press every key with the fixtures running and confirm the right function fires.

Decide how each key should behave. Latching scenes and colors work well as toggles. Strobe, blinder, and fog hits are better as flash buttons that run only while the key is held, which needs the plugin to send a Note Off when you release the key. Check that setting in the plugin before you rely on it.

On a Stream Deck +, set the dials to send control change (CC) messages and map them to sliders for group intensity or chase speed. MIDI CC has 128 steps (0–127), which is fine for a dimmer and too coarse for precise pan and tilt.

The same MIDI route can trigger a hardware DMX controller if it has a MIDI In port. Many compact scene controllers can start scenes, chases, or blackout from MIDI notes. You will need a USB-MIDI interface between the computer and the controller's 5-pin MIDI In, plus the note chart and receive-channel setting from the controller's manual.

Method 3: Bitfocus Companion

Companion is free, open-source software built for button panels in live production. Current versions come as ready-made installers for Windows, macOS, and Linux, and it also runs on small single-board computers. Older guides that tell you to compile it from source are out of date.

Companion drives the Stream Deck directly over USB, so quit the Elgato Stream Deck app before you start it, or use Companion's plugin inside the Elgato app if you want to keep both. Then:

• Add a connection for your lighting software or console. Companion has modules for many lighting programs and consoles, plus generic OSC, MIDI, Art-Net, and sACN connections. Check the module list for your exact software and version.
• Assign actions to keys: go on a cue list, flash a playback, set a fader level, or tap tempo.
• Add feedbacks where the module supports them, so a key changes color when its cue is live or shows a fader level as text.
• Chain actions with delays when one key should do several things, for example start an intro chase, wait 8 seconds, then release it and bring up a static look.

The generic Art-Net connection lets a key set DMX channel values directly through an Art-Net node, with no lighting software in between. That is handy for a house-light dimmer or a single fixture. Don't send Companion's Art-Net to a universe your lighting software is already using unless the node is set up to merge two sources, or the two will fight over the same channels.

The trade-off is more moving parts: Stream Deck, Companion, the network, the lighting software, and the DMX interface. Test the whole chain at the venue, not just at home.

How to lay out the keys

• Group by function. Keep colors in one row, positions in another, effects and chases in a third. Your hand learns rows faster than scattered keys.
• Put a safe look in the same corner of every page. A warm front wash at a fixed level with moving heads parked on a harmless spot gets you out of any mistake.
• Keep risky keys at the edge. Strobe, audience blinder, full white, and fog go on outer keys, set as hold-to-run, not next to the colors you press all night.
• Use the key display. Tint color keys with the color they call and label positions by target, such as "Vocal" or "Floor," not "Pos 3."
• Limit page changes. Anything you need during a song should be on the home page. Put the page-back key in the same spot on every page.

Reliability checks before the show

• Turn off sleep, screen savers, and automatic updates on the host computer. On Windows, disable USB selective suspend in the power plan so the Stream Deck and DMX interface don't drop out.
• Plug the Stream Deck and the DMX interface into ports on the computer itself, not an unpowered hub.
• Press every key with the rig running after load-in, and check the safe look and blackout first.
• Know your manual fallback. If the Stream Deck stops responding, you should be able to run the show from the software's on-screen buttons or a hardware controller.
• Export the Stream Deck profile or Companion configuration and keep it with the lighting show file.

FAQ

Can a Stream Deck control DMX lights without a computer?

No. A Stream Deck always needs a host running software. The host can be small, though: Companion on a single-board computer can send Art-Net to a node, which then outputs DMX to your fixtures.

Is MIDI or Companion better for Stream Deck DMX control?

Use MIDI if your show lives in DMX software with MIDI learn and you only need triggers. Use Companion if a module exists for your software or console and you want status feedback on the keys, chained actions, or control of other show gear from the same panel.

Does a Stream Deck work with QLC+?

Yes. The simplest options are keyboard shortcuts on Virtual Console buttons or MIDI through a virtual port, mapped with Auto Detect in each widget's External Input settings.

Can a Stream Deck trigger a hardware DMX controller?

Only if the controller has a MIDI In port. Connect a USB-MIDI interface from the computer to the controller, set the controller's MIDI receive channel, and map keys to the notes listed in its manual.