Automatic speaker calibration is an option on many receivers that makes it easier to calibrate the speakers. The receiver sends exam sounds to every speaker and subwoofer, and displays the audio having a microphone. Also bundled is a constructed-in ten-band parametric EQ providing Fantastic sound output and room optimization. Protection: https://4zoneamplifier20594.blogdon.net/new-step-by-step-map-for-4-zone-amplifier-50415217