Bose SoundTouch SA-4 Amplifier (Black) Easily connects to your choice of speakers for powerful sound anywhere around your home-even outdoors Bose proprietary signal processing enables full, rich lows at nearly all listening levels Wireless access to Internet radio, music services and your music library Premium remote control lets you use presets, control volume, skip, pause and power on/off with the touch of a button Sound Touch SA-4 amplifier is compatible with a variety of speakers