DMX

The digital control protocol that lighting consoles use to control fixtures.

How it works in practice

DMX sends a stream of numbers from a lighting console to fixtures along a daisy-chained cable. One chain, called a universe, carries 512 channels. Each fixture is given a starting address and uses as many channels as it needs: a simple dimmer might use one, a moving light can use dozens for colour, position, gobo and focus. Larger shows run several universes over a network and convert back to DMX near the fixtures. Wireless DMX transmitters are common with battery uplights.

You do not need to program it. What matters to a planner is that anything on DMX can be pre-programmed into cues, then played back on a single button at the right moment. That is how a room goes from dinner amber to dance-floor colour, or snaps to black for a finale.

How to handle it

1. Ask the lighting company which fixtures are on DMX control and which are stand-alone or on the venue’s house system.
2. Find out how the venue’s house lights are controlled. In many hotels they are on a wall panel, not the console, so a blackout needs a venue staff member at the switch.
3. Write every lighting change as a cue in the run of show, with the timing and who calls it.
4. Collect lighting cues from every tech rider, especially for a stage illusion act, where a blackout is part of the trick.
5. Book programming time on site. Pre-programming offsite helps, but cues still need focus and checking in the room.
6. Rehearse each cue at least once with the performer or speaker.

Questions to ask

• Where will the lighting operator sit? Usually at front of house, with a view of the stage.
• Can the emergency and exit lighting stay on during a blackout? It must, and the act has to work with it.
• What happens if the wireless signal drops: do fixtures hold their last look or go dark?
• Is there one operator for the whole night, or a hand-off after dinner?

Related tools

The run-of-show template has a lighting column for cues, and the performer tech rider template asks acts to list theirs in advance. See the production schedule entry for fitting programming time into load-in.