Marshall Kilburn II Portable Bluetooth Speaker with Over 20 Hours of Playtime The most powerful speaker in its class, the Kilburn II delivers extremely clear lows, highs, and mids. On the top panel, you’ll find analog control knobs to adjust the bass, treble, and volume, allowing you to get exactly the sound you want. TRUE STEREOPHONIC (360° SOUND) This little marvel uses True Stereophonic technology, a unique multidirectional audio diffusion technology from Marshall. Experience absolute 360° sound quality, no matter your position relative to the speaker. With a total power of 36 watts, it delivers clear and powerful sound that pushes the usual limits for speakers of this size.