< p> A design combining superior operability and beauty. And introducing a new technology, Twisted Flare Port, for clear and tight bass. A subwoofer that will match a wide range of speakers and interiors. PWM digital drive high efficiency amplifier and dual feedback circuit New Twisted Flare Port contributes to clear and tight bass Advanced YST II (Yamaha Active Servo Technology II) 25 cm (10”) cone woofer with square wire voice coil Beautiful design will match a wide range of speakers and interiors Front control panel for easy control System control and Auto standby< /p>