DMX512: The Universal Language of Light

What It Is

In the early days of computer-controlled stage lighting, every manufacturer built its own proprietary control system. A lighting console made by one company could not communicate with dimmers or fixtures made by another. If a theater owned equipment from three different manufacturers, it might need three separate control systems to run them. For lighting technicians, this meant learning multiple incompatible systems and dealing with constant compatibility headaches. The frustration was widespread, and by the mid-1980s, the industry recognized that a universal standard was essential.

Why It Matters

At the 1986 annual conference of the United States Institute for Theatre Technology (USITT) in Oakland, California, a working group from the Engineering Commission set out to solve the problem. The result was DMX512, a digital communication protocol that allows a single cable to carry control data for up to 512 individual channels. The standard was deliberately kept simple, robust, and flexible. A DMX cable can be abused in ways that would destroy most data cables and still function. The protocol was revised in 1990 and formally adopted as an ANSI standard in 2004, but the basic framework has remained fundamentally the same for nearly four decades. DMX512 transformed the lighting profession. For the first time, any console could control any dimmer or fixture from any manufacturer. It also coincided with the development of intelligent lighting fixtures, LED technology, fog machines, and moving heads, all of which rely on DMX for control. Today, DMX512 is the global industry standard used in theaters, concert venues, arenas, nightclubs, houses of worship, architectural installations, and virtually every other environment where programmable lighting exists.