I have a 2 pairs of speakers - 2 of them are Yamaha CM12V - rated program at 500W daisy chained together on ch 1. The other pair of speakers are a Yamaha SM15111 - daisy chained to a Yamaha C115V - both program rated at 500W - on ch 2 - all the speakers have nominal impedance of 8 ohms. If the QSC MX1500a amplifer is rated at 330W per channel at 8 ohms, am I underpowering the speakers?