The bottom line is how are the two amplifiers protected??? It could be that there would be no problem and, on the other hand, you could have smoke. In any case, the unused amp would provide a parallel load for the operational amp.

My bottom line is that I would NOT do what you are suggesting. I just don't think that the risk of an accident is worth it.

Just one man's opinion.

The Rat. M80s, VP-150, QS8s, SVS PC 20-39+, OPPO, Onkyo 703s, Harmony 880 Sony 60" SXRD HDTV