Digital Multiplex (DMX) is a method and technology used by stage and lighting professionals to control lighting instruments. Though it is most often used for stage lighting, buildings with a central lighting control board often use DMX technology to control their lights. On a DMX console, the presence of DMX dimmer technology means the difference between being able to turn a light instrument on and off and the ability to control the intensity of the light and speed with which it comes on. Dimmers can be hardware or software, and they can be controlled manually or automatically, and are similar in appearance to the sliding faders used on audio control interfaces.
A DMX dimmer can be a standalone device that is plugged into a DMX chain. It can also be part of a larger DMX interface. A DMX dimmer can appear on both hardware and virtual interface consoles. Some interfaces allow control both through a virtual dimmer on a computer monitor and through a hardware dimmer that the user can move with his hands. Other interfaces allow the user to program automated DMX dimmer controls.
DMX dimmers are most often seen in event lighting, which generally means clubs, parties, and performances. Any DMX lighting interface with dimmer control has a DMX dimmer. Not every light works with a DMX dimmer, so not all DMX-based lighting interfaces have DMX dimmers. Without a DMX dimmer, the user can usually only turn the lighting instruments on and off, and would not have the ability to apply more intricate lighting controls like fading in or dimming the lights.
Lighting controls without a DMX dimmer are most often seen on moving lights like those seen in a dance club. Sometimes, club lights have their own set of controls on the lighting instrument itself. This allows the lighting designer to program light patterns and change settings while she has access to the light, but this setup does not allow for changes to the light patterns after the light is mounted out of reach.
DMX technology is popular for show lighting because it is a reliable form of lighting control, which is important when running performances. It offers much greater reliability than other lighting control methods like Ethernet or wireless control. Its reliability makes DMX the main type of technology used for performance lighting. Even small venues usually used some form of DMX technology to control their lights. Many dance clubs also used DMX-based lighting technology to give their clubs unique atmosphere.