subject: Digital Communications In Audio Visual Design Dmx Lighting Control [print this page] . DMX is basically used to control timings and intensities, and may be as simple as a Christmas light installation (probably the simplest DMX lighting installation is the blinking on and off of tree light configurations), or as complex as the lights and the sound effects for a Broadwaymusical.
DMX 512, which is now the standard form of DMX control, came into being as a response to the disparate and mainly incompatible formats for lighting and sound control being used in the 1980s. It is now the industry standard method for linking controllers, dimmers and more complex special effects actuators including timers and fog machines.
The most common architecture for a DMX lighting network is the ?aisy chainotherwise known as a drop network in which multiple nodes are linked together in a chain. The lighting network always has a DMX 512 controller at its heart the master of the network and any number of other input devices and machines as slaves. In practical terms, this means that sound, lighting and effects cues may be mastered from one location by the stage or effects crew.
DMX 512 adapters may be used wirelessly, transmitting their signals to receivers that then control the actions and brightness of all the lights in a system or chain. DMX lighting of this nature is often used in architecture and art installations, particularly in modern buildings where rotating sections of light colour and brightness may serve to add ambience for example in a bar, or in an iconic installation such as the London Eye.
Wireless DMX 512 operation can theoretically take place over distances as great as 3,000 feet When specifying wireless DMX lighting it is normally thought that 1,000-1,500 feet is the safe operating range at these distances the reliability of the signal is practically guaranteed.
DMX can really be used for pyrotechnics, because it has no built in system for checking errors along the daisy chain.
The technical term for DMX lighting network is ?niverse ?r to give its full title ?MX universe Very large lighting applications are overseen by operating consoles or control desks that control multiple universes.
There are normally no more than 32 devices communicating on a single DMX network. It is possible to expand the DMX lighting network using specific DMX splitters, which can use parallel buses to double the number of devices used. A DMX connector has five pins male to five female holes, though some manufacturers of what they term DMX lighting equipment have ignored the conventions and produced three or seven pin variants, which may need to be modified using extra cabling to connect into a normal daisy chain.
The standard DMX lighting cable is called an XLR-5, and is found in everything from public address systems to microphone linkups to mixing desks and DJ decks. Interestingly enough, Davey DMX (an early hip hop DJ) named himself after these cables!
