Yes, Elden, that would be passive biamping. Also, and this is more than simply semantics, since it's the cause of most of the misconception about passive biamping, there is no "unused amp" if a full 7.1 speaker setup wasn't being used. The receiver or separate amplifier has only one power supply section, with a limited capacity; the output transistors in each channel act as valves to measure out the needed amount of power from the power supply section, but they have no power of their own to add. So, channeling the power through two sets of output transistors(one previously unused)into the speaker, rather than one, can't increase power in any way.
