JBL Duet uses patent pending Tangential Strain Relief (TSR) transducer technology. With TSR Duet delivers extra bass and lower distortion as a result of controlled linear excursion of the speaker. The neodymium magnet creates more power and sensitivity. MODEL: DUETAL VENDOR: HARMAN MULTIMEDIA FEATURES: JBL Duet- Aluminum finish Sophisticated two-channel sound. The JBL Duet speaker system provides smooth and accurate sound for any portable music player or computer. Duet uses patent pending Tangential Strain Relief (TSR) technology. With TSR you get extra bass and lower distortion. The neodymium magnet creates more power and sensitivity. Duet also uses a proprietary port design which enhances the bass performance. Volume Control Knob and Power Indicator LED. SPECIFICATIONS: FREQUENCY RESPONSE - 60 Hz ~ 20 kHz SIGNAL-to-NOISE - gt; 80dBINPUT IMPEDANCE - gt; 5K INPUT SENSITIVITY - 400 mV rms for rated power outputOUTPUT POWER - 12 watts total (10% THD+N)DRIVERS - Phoenix TSR trans