KEF LSX II Powered Speakers with Wi-Fi, Apple AirPlay 2, Google Cast, and Bluetooth (Pair) LSXII delivers room-filling, natural, accurate sound from any source thanks to the knowledge and experience of KEF's talented engineers and the iconic Uni-Q driver array. Product Highlights: Frequency response: 54-28,000 Hz (±3 dB) Bi-amped design with separate Class D woofer and tweeter amplifiers for greater headroom and lower distortion Woofer amplifier power: 70 watts Tweeter amplifier power: 30 watts