Relackout

DMX output: Art-Net, sACN and USB DMX

In Settings, choose which universes Art-Net broadcasts, set the universe base, learn sACN, and assign universes to USB DMX interfaces.

Chapters

There are three ways to get a signal to your lights: Art-Net or sACN over the network, or a USB DMX interface plugged straight into your computer. This guide walks you through setting up all three from the Settings screen: choosing which universes to broadcast, getting the universe base (0 or 1) right, changing the name your network sees, and assigning a separate universe to each USB DMX interface. It assumes you’ve already patched your fixtures — if you haven’t, start with Patching and the address map.

Where output settings live

  1. Open Settings from the home screen.

    General Settings screen open; the DMX Outputs heading is already visible near the bottom.

  2. Find the DMX Outputs heading below the settings buttons.

    DMX Outputs heading highlighted; below it the Art-Net card, status Connected.

The Art-Net card

The first card is Art-Net. The status is in the top right: Connected. Below it is the address and port Relackout sends Art-Net packets to (for example 192.168.1.255:6454; the exact address depends on your network). Packets go out as a broadcast on your local network, so every Art-Net node on it can see them.

  1. Click the on/off switch on the right of the card (turn it off).

    Art-Net card switch off (left, gray); status now reads Not connected and the address line is gone.

  2. Click the switch again (turn it back on).

    Art-Net card switch on again (right, accent color); status back to Connected, address line shown.

Choosing which universes to broadcast

The most important setting is here: Broadcast universes. Each button, U1 through U4, is one universe; only the selected ones get sent over Art-Net. The whole Demo Venue rig is on Universe 1, so only U1 is currently on. Deselect them all and a warning appears under the row: No universe is being broadcast.

  1. Click U1 (turn it off).

    U1 no longer selected (highlight gone).

  2. Click U1 again (turn it back on).

    U1 selected again (highlighted).

Only selected universes are sent over Art-Net. Output pauses for 1.5 seconds while a change is applied. So toggle a universe during setup, not in the middle of a show.

Universe base: 0 or 1?

Art-Net numbers universes from zero: by default, Relackout’s Universe 1 goes out on the wire as universe 0 — that’s the standard. Some nodes and visualizers count from 1 instead.

  1. From the Universe base list, choose 1 (1-based).

    Universe base list showing 1 (1-based).

  2. Reselect 0 (standard, 0-based).

    Universe base list showing 0 (standard, 0-based) again.

The name your network sees

At the bottom of the card are two name fields: Short name (ArtPollReply) and Long name (ArtPollReply). Art-Net tools on your network list Relackout under these names. If there’s more than one computer on the same network, giving each a distinct name makes life easier.

  1. Type “Demo FOH” into Short name (ArtPollReply).

    Short name field filled with Demo FOH.

  2. Type “Demo Venue – FOH” into Long name (ArtPollReply).

    Short name Demo FOH, Long name Demo Venue – FOH, both filled.

sACN (E1.31)

The other network option is sACN, also known as E1.31; its card sits right below USB DMX. Like Art-Net, it runs over the network, but it uses multicast to send packets only to the devices listening to that universe. Use it if your node or lighting desk speaks sACN. The sACN output switch turns it on. Priority decides which source wins when more than one sends the same universe — the higher number wins. Next to it, Universes is where you choose which universes go out over sACN. E1.31 multicast output. Shares the Art-Net license entitlement.

sACN has its own switch, separate from the Art-Net one, and is off by default. You configure it the same way as Art-Net: pick its universes with the U1–U4 buttons (all four are selected at first, and at least one always stays selected) and set Priority (100 by default, 0 to 200). Like the rest of this section, it applies only to this workspace.

USB DMX status

The third option is USB DMX: plug an interface like the ENTTEC Open DMX USB into your computer and drive the lights directly.

  1. Scroll down to see the USB DMX card.

    USB DMX card in amber Not connected status; two port rows below, both tagged Not connected.

  2. Click Retry.

    After clicking Retry, the card is back to Not connected.

Multiple USB DMX interfaces

With multiple USB DMX devices, assign a universe to each. With no assignments the first device broadcasts Universe 1. This workspace already has two interfaces set up: one assigned to Universe 1, the other to Universe 2. Neither is plugged in right now, so both show the Not connected tag.

  1. From the second port row’s universe list, choose U3.

    Second port row's universe list now shows U3, not yet saved.

  2. Click Save assignments.

    Assignments saved message visible; the second row stays on U3.

What’s next

To recap: on Art-Net, broadcast only the universes you use; if the lights don’t respond, check the universe base; turn on sACN if your gear asks for it; and with USB DMX, give each interface its own universe. All of it is per workspace. Coming up in this section: the hardware setup for the Relackout USB-DMX interface, connection settings in more depth (IP, exporting ArtPollReply names), and a conceptual look at Art-Net versus sACN.

Updated: October 8, 2026

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