YAMAHA YST-SW500 有源 10" SUBWOOFER 120 WATT 連原廠搖控器 在華仁購買 原價$4300 玩SURROUND 必備 少用 9成新 北角取 YOU CAN SEE REVIEW FROM HERE: http://www.dealtime.co.uk/xPF-Yamaha_YST_SW500 The Yamaha 10" YST-SW500 subwoofer delivers Natural Sound quality throughout. This subwoofer system employs Yamaha Active Servo Technology, which Yamaha developed for reproducing higher quality super-bass sound. This unit does not only enhance bass frequency response of sound output in your audio system, but, by reproducing the bass frequencies, the subwoofer permits your existing amplifier and speakers to operate under less strenuous conditions, improving overall system performance. This unit can be added easily to your existing audio system by connecting to either the speaker terminals or the line output (pin jack) terminals of the amplifier.