Intelligent Amp Assign automatically assigns amplifier channels to certain speakers, depending on what functions are selected. For example, in a 9.1-channel system, when Zone 2 is off, all 9.1 channels will be used in the Main Zone. However, when Zone 2 is on, power to the two surround back channels will be directed to the two speakers in Zone 2 and the Main Zone will receive 7.1 channels of power. Similarly, when CINEMA DSP HD3 is on, the two Rear Presence speakers will be powered and not the two surround back speakers. When CINEMA DSP HD3 is off, this situation is reversed. Thanks to Intelligent Amp Assign, there’s no need to switch the speaker cables on the rear of the receiver—one more way Yamaha makes your life a little easier.