ART HeadAMP 4 Eight Output Stereo Headphone Amplifier Overview: The HeadAmp4 offers 1/8th-inch as well as 1/4-inch inputs and outputs as well as lower noise, lower distortion and more output in a new custom extruded stackable metal case Ideal for virtually any home or project studio, the ARTcessories HeadAmp4 easily adds additional headphone outputs to any mixer, computer audio interface, workstation , iPod, media player or laptop without creating any additional load on the existing headphone source.