How to connect DMX lights to a Mac

A Mac has no DMX output of its own, so every rig needs one piece of hardware in between. There are exactly three kinds worth buying: a USB-to-DMX adapter, an Art-Net node, or an sACN node. HitLight supports all three, and which one you want depends less on your budget than on how far the lights are from the laptop.

Should you use a USB adapter or a network node?

Use a USB adapter if the laptop sits next to the rig and you want the fewest possible things to go wrong. Use a network node if the laptop is more than a few metres away, if you want a locking connector, or if you expect to grow past one universe. Experienced operators tend to prefer a node, and the reason is almost always mechanical rather than technical: a USB plug can be kicked out of a laptop, and an etherCON or locking XLR cannot.

The signal is identical either way. Art-Net and sACN both carry ordinary DMX512 over an ordinary Ethernet network; the node at the far end converts it back to a five-pin XLR socket the fixtures already understand.

Which DMX interfaces work with HitLight on a Mac?

SIUDI output exists in HitLight but is experimental until hardware verification is complete. Other serial interfaces may appear under Advanced; they are not part of the supported beta matrix. The full, maintained list lives on supported hardware.

How do you actually connect it?

1. 1

   Plug the interface in and open the Mac app

   A USB interface is driverless on macOS. A network node needs to be on the same network as the Mac — wired if you have the choice, because Wi-Fi adds latency you will see in fast chases.

2. 2

   Patch your fixtures before you connect the output

   Choose the exact profile, DMX mode, universe and start address for each fixture. Getting the mode wrong is the single most common reason a light does something unexpected — a fixture patched in 8-channel mode and set to 16 on the unit itself will read the wrong channels for everything.

3. 3

   Confirm the address on the fixture itself

   Walk to each light and read the address off its own display. Do not trust the patch sheet — trust the fixture. Confirm the model, the DMX mode, the universe and the start address on the physical unit.

4. 4

   Bring one channel up slowly

   Test channel by channel at low values before you run a scene. If a fixture responds on the wrong channel, you have an addressing or mode mismatch, and it is far easier to find now than during a show.

5. 5

   Test Blackout before anyone arrives

   Press it. Watch the rig go dark. Do this at every venue, every time. It is the one control you will need in a hurry, and the only way to know it is wired correctly is to use it.

Nothing is happening. What now?

Work down this list in order — it is roughly the order of likelihood.

• Check you are on the Mac app. The browser app authors and visualises shows and acts as a remote, but it cannot output DMX. This catches more people than anything else on the list.
• Check the fixture's own address and mode against what you patched. A mismatch here produces the classic symptom of one fixture responding to another fixture's channels.
• Check the universe. A fixture patched to universe 2 will never respond to an interface outputting universe 1.
• Terminate the end of the chain. A 120Ω terminator on the last fixture is not optional folklore; without it, long runs produce flicker that looks exactly like a software fault.
• Try a different cable. Microphone cable is not DMX cable. It often works, and then one day it does not.
• For a network node, check both devices are on the same subnet. Art-Net in particular has historically used its own address range, and a node on 2.x.x.x will not hear a Mac on 192.168.x.x.

What happens once it works?

Once a fixture responds, the rest is authoring. HitLight's assistant will program scenes from a plain-English description of the look you want, working from the profile you patched and the values actually on the wire rather than guessing at your fixture's channels. Auto Show will drive the whole rig live from the music in the room. Both are optional: the matrix editor, cue lists and timeline are there if you would rather build every step by hand.

Before you run anything automatic in front of people, read lighting safety — particularly the list of channel types automatic control refuses to touch.