E-MUs new 0204 USB (Universal Serial Bus) Audio Interface is the ultimate portable 2-in/4-out USB (Universal Serial Bus) audio interface for PC & Mac offering pristine 24-bit/192k Hz recording & playback direct monitoring & a host of professional features in a compact USB (Universal Serial Bus) bus-powered package. The 0204 USB (Universal Serial Bus) sets a new standard in portable USB (Universal Serial Bus) audio providing users with two Class-A preamps that can be run independently or in stereo to amplify guitars keyboards or microphones with individual ground lift switches for optimal audio performance.