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 New Twisted Flare Port Produces Clear And Tight Bass The all-new Twisted Flare Port takes advantage of extensive subwoofer development experience. The flared, gently twisting shape diffuses the vortex of air generated around the edge of the port, creating a smoothflow of air. This reduces extraneous noise not present in the originalinput signal and provides clear, accurate low frequency reproduction. From special effect sounds in movies to the atmosphere ofa live venue, you hear bass that is clear, tight and realistic. Specifications NS-SW300 Subwoofer Driver 25 cm (10”) cone Output Power 250 W Frequency Response 20–160 Hz Advanced YST Yes High-Efficiency Power Amplifier Yes Twisted Flare Port Yes BASS (Bass Action SelectorSystem) Yes Auto Standby Yes Standby Power Consumption 0.3 W System Connector Yes Dimensions (W x H x D) 350 x 366 x 420 mm; 13-3/4” x 14-3/8” x 16-1/2” Weight 18 kg; 39.7 lbs.