The SC206-204 is an audio adapter that converts unbalanced audio signals to balanced audio. The converted signals provide better sound quality and greatly reduce noise over long transmission lengths. This is a passive device that may also be used to convert balanced signals to unbalanced signals as well. The SC206-204 is designed to convert standard computer audio output to balanced audio. It has an excellent bandwidth and is ideal for most commercial-user applications. Since the SC206-204 is a passive device, there is no need for an external power source. Simply make the audio connections and it is ready to go. The SC206-205 is also designed to convert unbalanced audio output from computers, DVD players, VCRs, etc. to balanced audio. The SC206-205 possesses superior bandwidth and is perfect for home theaters as well as marketing and sales presentations.