Ordinary amplifers, even good ones like?the Newcastle high current amps, dissipate over half of their input power into heat. But Sherwood's new TruDigital? amps are over 90% efficient and unlike other less advanced Class D amplifiers currently on the market, our TruDigital? technology maintains a digital signal path from amplifier input to the output stage. The ability to eliminate one step in the normal amplifier chain means the sound is cleaner with better bass and imaging. Sherwood's Newcastle R-903 has 100 Watts x 6 (Surround Modes), DTS-ES Discrete and Matrix, Dolby Digital Surround EX, DTS Neo-6, Dolby Pro Logic II; Movie and Music. Dolby Virtual and 19 DSP Modes. With 2 Optical Digital Inputs, Coaxial Digital Input, Optical Digital Input, On-Screen Display and Preprogrammed 8-unit Remote Control with Macro Capability. Frequency Response: 20 Hz to 22 kHz.