Cable Configurations and Connectors

• Semi-pro DMX systems and all professional microphones use cables with a total of three wires and three-pin XLR connectors. Consisting of positive, negative, and wrapped or braided ground (serving as shielding to prevent radio frequency interference), the cables are terminated with one XLR female connector for signal input and one male XLR connector for output. High-end professional DMX systems employ five-pin XLR connectors with five-conductor cable. A standard microphone cord will neither fit nor operate DMX devices with the five-pin configuration.
  
  

Cable Capacitance

• The primary difference between DMX and mic cable is cable capacitance. Capacitance essentially is a voltage rating that dictates the amount and type of current the cable is capable of passing between devices. Microphone cables are designed for analog audio signals and are of high-capacitance design to allow higher voltages typical of analog audio signals. DMX cables are designed for transferring digital information and are of low-capacitance design required for low-voltage digital information signals.
  
  

Substitution Issues

• Substitution of a high-capacitance mic cable for DMX use may cause DMX devices to malfunction, behaving erratically or not functioning at all. Substitution of a low-capacitance DMX cable for microphone use may cause audio quality problems, especially in demanding situations such as recording, and should be avoided.
  
  

Avoiding Cable Mix-ups

• Since DMX and mic cables cannot easily be identified visually, cables or connectors should be color-coded or otherwise clearly marked with a numerical or alphabetical identification mark. Although some DMX cable manufacturers print "DMX" along with cable specifications on the outer insulation of the cable, this mark can be difficult to read and will wear off over time. Other manufacturers do not mark the cable at all, and only include cable manufacturer type and specifications. This is another reason to clearly mark all your cables.
  
  

Invest in Dedicated Cables

• Investing in the best cables you can afford for each different application will pay dividends in equipment reliability and performance. While cables, especially DMX cables, can be expensive, proper care and storage will make them last for many years. Avoid placing any cables where they will be trod upon or crushed by heavy equipment. Coil cables loosely, and use velcro-type fasteners or twist ties. Store DMX and mic cables in separate and clearly marked, loose-fitting, clean, dry cases or bags for storage or transport.