Powerful Sound and Bigger Bass for Better Parties The prominent ULT button gives you access to two exciting bass modes. Powerful bass to feel the beat and get you dancing, or deep bass boost for low-frequency sound that will make your heart tremble. Hit the Button. Feel the Bass. Press the ULT button to enjoy the powerful sound of ULT1 and ULT2. Select ULT1 for deeper, lower frequency bass. Select ULT2 for powerful, punchy bass.² Surround Yourself in Sound 360º Party Sound carries powerful sound to every corner of the room. Four tweeters deliver clear sound to both the front and rear of the speaker, with two mid-range speakers for vocal clarity. Feel the bass sound, thanks to the large X-Balanced Speaker Unit. Together, they let everyone in the room feel the power of the music, wherever they are. Powerful Sound with X-Balanced Speaker Unit Sony's X-Balanced Speaker unit features a non-circular diaphragm, for an increased surface area compared to conventional speaker units. The approx. 320 mm x 320 mm large woofer unit is designed for clear and deep bass sound. A Richer, Clearer, Deeper Experience The non-circular diaphragm not only maximizes the area of speaker diaphragm, but it also increases sound pressure for deeper and punchier bass, less distortion and greater vocal clarity. Altogether, it elevates your listening experience.