Quick Summary The iconic KEF Muo speaker returns with a racetrack driver, powerful bass, Bluetooth with aptX Adaptive, and Auracast support. KEF's Muo speaker was introduced in 2016 to deliver class-leading portable audio, and it's attracted tons of rave reviews. Now there's a new model with a promise of even better audio and room-shaking bass. KEF says that enables the Muo to deliver booming bass with low distortion and power consumption. It gets 10W of Class D amplification with a further 30W of amplification reserved for the racetrack driver.