Can you say RUNNING TOO HOT! It may seem like a good idea but in the end the amp will run too hot and if played this way overtime will burn up. Infinity speakers are known for tearing up amps that are incapable of dealing with the impedance swings. I would try something more like a good mosfet design, like a ADCOM 555, or even better 2 of them bridged!
Matt M
Matt M