Ear Force DX11 Recertified Dolby Digital 7.1 Surround Sound with your favorite games and DVD movies Dolby Pro Logic IIx reproduces full-range special effects in surround channels Amplified stereo sound boosts game audio for added realism to your games Independent controls for game audio and chat volumes Eliminates game sounds picked up by chat mic Mic monitoring allows you to hear what you're saying Hear XBOX LIVE chat plus stereo game sound Heart-thumping bass boost adds sonic realism Powered by USB  no AC adapter or batteries required Also works with PC