HQ Power Qubic 21300 power amplifier has been designed for continuous use in the most demanding of venues, fitted with twin cooling fans they can operate under the most difficult conditions. These amplifiers have a high damping factor, so they produce a clean clear transparent sound. HQ Power Qubic 21300 professional amplifier feature a well designed limiter which holds down peaks to avoid distortion and damage to your speakers. The amplifiers can be run in conventional stereo mode or parallel mono or you can even bridge the output.