My position on the Emo XPA5/3 is for the money, they represent great value.
But I have seen no proof that they can produce the same all channels driven power under sustained conditions (meaning length of time) that a Parasound A51 with 2.2KVA transformer can.
1200VA does not = 2200VA.
And Emotiva's 60,000uF does not = Parasound's 164,000 µF caps
To me, it looks like Emotiva's multichannel power ratings are voodoo power
The XPA1 and XPA2 are different story, they really do seem to have the balls to go toe-to-toe with the big name, more expensive amps.
But on their multichannel amps, there power supplies are not that much bigger than what used to be in upper end class A/B receivers. The Pioneer Elite 59TXi for instance, had 750VA and my '78 Sansui quad receiver that was rated for 4 X 60 watts per ch (!) had 960 VA!
Emo's 1200 VA transformer for 5 channels is skimpy for supposed 1000 watt capability.
I have an ext amp designed for electrostat speakers that has a 1200VA torroidal transformer and rated for 300 watts @ 8 ohms & 600 watts @ 4 ohms for only 2 channels, pretty similar to the XPA2. Unless the laws of electricity have changed, 600 total watts/5 channels kind of equals 120 watts per channel. And my amp has 18 output transistors per channel compared to Emotiva XPA5's 6 per channel.
Please tell me how it can come close to the per channel output of my Innersound amp.
It can't. Sorry, I don't believe it.
The fact that some of you very familiar with Emotiva have confirmed it's hard to pin them down on their testing conditions and question how long it can sustain that power, supports my own beliefs.
For $900, the XPA5 is still a steal, but we shouldn't delude ourselves that it will do the same sustained power as an A51. There's a reason an A51 and similar amps cost much more & it's not just the name brand.
I would certainly consider an XPA1 or XPA2 amp in a heartbeat, but I think the XPA5/3 are way over-spec'd. They probably work fine for many but they would not be any better than a robust receiver for my needs.