I have Salon 2s too. All of your amp choices are of such high quality and so high power I'd bet you'd be hard-pressed to hear any differences. But if you want to be discerning anyway...
For complex multi-driver systems like the Salon 2s I tend to prefer amps that are a good voltage source, just because the loads of the drivers and complex crossovers tend be demanding. The AR amp is not specified to do well into low impedance loads, though with 450w/ch how bad could it be? Still, I'd pass on the AR.
I've always found McIntosh amps to be weird animals, because they add a lot of cost and weight in those output autoformers, and I prefer the money gets spent on the power supply & output amplification stage for high current, but that's just me. I also don't care much for McIntosh styling, but that's pure personal preference, of course.
The Halo is a nice amp, and claims better low impedance performance. Parasound is a good company, but I don't like the overseas manufacturing in such premium products.
The Classe amps are nice too. Of your list I'd probably choose one of the Classes.
If you can afford it, the new Krell 302e looks very interesting. As usual for Krell, it's claimed to be a constant voltage source down to 2 ohms, and it's a new design, so the standby power is only 2w. At 600w/ch into 4 ohms (and likely more, knowing Krell) it has a ridiculous amount of power. It'll probably last forever too, just like the McIntosh. I've always admired Krells.
I also like the Levinson amps (that's what I run). Another constant voltage choice. Very innovative designs, and perhaps a better value than the Krells, especially if you stay with the lower wattage models. My experience with Levinson service leaves a bit to be desired, but that was on a CD player, and their amps are well known to be absolutely reliable.
For complex multi-driver systems like the Salon 2s I tend to prefer amps that are a good voltage source, just because the loads of the drivers and complex crossovers tend be demanding. The AR amp is not specified to do well into low impedance loads, though with 450w/ch how bad could it be? Still, I'd pass on the AR.
I've always found McIntosh amps to be weird animals, because they add a lot of cost and weight in those output autoformers, and I prefer the money gets spent on the power supply & output amplification stage for high current, but that's just me. I also don't care much for McIntosh styling, but that's pure personal preference, of course.
The Halo is a nice amp, and claims better low impedance performance. Parasound is a good company, but I don't like the overseas manufacturing in such premium products.
The Classe amps are nice too. Of your list I'd probably choose one of the Classes.
If you can afford it, the new Krell 302e looks very interesting. As usual for Krell, it's claimed to be a constant voltage source down to 2 ohms, and it's a new design, so the standby power is only 2w. At 600w/ch into 4 ohms (and likely more, knowing Krell) it has a ridiculous amount of power. It'll probably last forever too, just like the McIntosh. I've always admired Krells.
I also like the Levinson amps (that's what I run). Another constant voltage choice. Very innovative designs, and perhaps a better value than the Krells, especially if you stay with the lower wattage models. My experience with Levinson service leaves a bit to be desired, but that was on a CD player, and their amps are well known to be absolutely reliable.