125W amplifier boosts up to two pairs of passive speakers for synchronized household sound experiences Signal processing technology adjusts the tonal balance automatically when the volume is changed, ensuring lifelike, ultra-clear sound at any volume Connect to the Bose Music App to further adjust the audio controls and create custom sound settings Bluetooth, Apple AirPlay 2, Spotify Connect, and Chromecast built-in connectivity allows for easy music streaming from compatible devices Analog and optical inputs let you connect accessories like CD players and vinyl record players for added versatility Sleek design and versatile installation options make it easy to fit this amplifier into your existing home sound system For the best sound experience, use the amp with Bose passive speakers and a Boss bass module, available separately