SIIG CE-S00022-S1 USB SoundWave 7.1 Pro USB audio adapter - easily add sound to any notebook or desktop computer S/PDIF optical output provides true 7.1 channel sound Includes S/PDIF Optical Adapter for true 7.1 channel sound Virtual 7.1 channel surround sound provides home-theater quality surround sound via headphones or stereo speakers Places speakers to preferred positions without moving actual speakers via Speaker Shifter USB audio adapter  easily add sound to any notebook or desktop computer S/PDIF optical output, with the included S/PDIF Optical Adapter, provides true 7.1 channel sound Virtual 7.1 channel surround sound, via Speaker Shifter feature, provides home-theater quality surround sound via headphones or stereo speakers Places speakers to preferred positions without moving actual speakers via Speaker Shifter software Reduces unwanted static and noises from D/A processing Easily control your multimedia output by using the integrated volume-up, volume-down, speaker mute and microphone mute button