Houses an Alpine Class D Amplifier Circuit and is now certified for Hi-Res Audio Playback ^^ Able to reproduce up to 40kHz frequency response ^^ Ultra-wide bandwidth coupled with the elevated S-Series design ^^ Features a new selectable remote turn-on circuit, a three-position switch that ensures the amplifier turns on and off at the proper times ^^ S2-A55V Amplifier is the perfect solution to power your sound system all in a single chassis