Compared to other wireless speakers on the market, this model stands out for its superior sound, versatility, and a particularly robust built-in subwoofer. The transmitter connects to three separate audio devices at once, including a TV, home theater system, CD microstereo, or MP3 player; an audio-channel control lets you switch between input devices. The transceiver uses a 2.4 GHz digital frequency to send a crisp, clean signal to the sphere which can be placed up to 100' away. The compact sphere delivers sharp, voluminous sound through two 1.5-watt speakers and a built-in 3-watt 2 1/2" subwoofer that eclipses the flat bass drivers on most wireless speakers and doesn't require extensive shelf space. A "learn remote" function allows you to use your audio device remote control directly from the sphere. Membrane buttons on top simplify switching between devices and adjusting volume and tone. The built-in LCD shows equalizer settings and a digital clock. Runs on AC adapter (included) or 6 C batteries (not included). Includes wall mount bracket. 8" Diam. (2 lbs.)