DESC: The D series features efficient Class D circuitry and a TC-X variable 30-350 Hz two-way electronic crossover with a steep 24 dB/octave high-pass or low-pass slope. The Advanced Instrumentation input circuitry virtually eliminates the possibility of radiated noise corrupting the signal path. Advanced buss technology and symmetrical circuit design improve imaging and reduce the overall noise floor for improved transient response. The PWM (pulse width modulated) MOSFET power supplie is stiffly regulated for consistently powerful bass response, while protection circuitry provides the most advanced protection on the market today. Q BASS Plus equalization offers up to 10 dB of boost, with a selectable center frequency, to enhance low bass response. Optional Q BASS Remote for listening position tuning of subwoofers.