Ok I'm here to report something that I think I would definately be able to pick up in a blind test. After listening to 'Into the Ocean' by Blue October both through the Denon and then through the Emotiva, I noticed something unmistakable. When the Denon is controlling things the voiced sound very loud when the bass isn't present. Then as soon as the bass kicks in both the voices and the rest of the higher frequency sounds seem to drop a notch. I've noticed this on several songs in the past, but it's the only one I played with both set-ups. Once I hooked the M80's back up to the XPA-3 (I was only switching the M80's back and forth to save time) the upper frequencies never dipped when the bass hit. They remained at the same level, and the bass simply came in as if out of another speaker somewhere altogether.
I'm certainly no electronics expert, nor an audio nut who knows the X's and O's of these amplifiers. But my guess is that the M80's pull a certain amount of wattage out of the Denon, then when the bass comes in heavy that wattage has to be split between the 6 inch woofers and the 4 inch woofers + tweeters that are handling the voices and other high frequency sounds. With all 5 channels driven there must not be enough wattage to fully supply all the power the M80's need to keep the high frequencies playing at the same level once the 6 inch woofers start to rob them. But with the Emotiva (I just read through the instrucion booklet that came with the amp and it says it pushes 200 watts at 8 ohms and 350 watts at 4 ohms. The website showed 200 watts at 8 ohms and 300 watts at 4 ohms... so I'm actually getting an extra 50 watts than what I'd bargained for... SWEET!!!), they have plenty of power to run everything equally.
That's my theory anyhow. I don't know what else could be going on, but I definately noticed a difference in that respect. Pixie dust - 1, math books - 0
