Pass XA 25 or Bryston 3B3?

I am a big fan of Nelson Pass, but his Class A amps put out LESS as the speaker impedance drops. Check the specs on your speakers and see if the impedance drops, especially in the low frequency region. Any drops below 6 ohms or so will work against the Pass amp. Too Bad!  You might check out the Strake Sound AD4.320. A great amp (check Google for a review by "Home Theater something or other") and it's on sale at 40% off for Black Friday. I just ordered one. Over 200 wpc available for Stereo into 2 ohms!

I am a big fan of Nelson Pass, but his Class A amps put out LESS as the speaker impedance drops.

That’s silly, and it’s the antithesis of a Class A amplifier design.  Anyway, although the Pass may not be the space heater the Krell is it’s still gonna generate a good bit of heat so not sure how much you’re really saving going that route.   But I’m sure it’d sound great with the Pulsars and probably would be more to your liking than the Bryston given your tastes and familiarity with the Krell.. 

What I’d consider doing with your budget is buying a used McCormack DNA 0.5 amp and send it to SMcAudio to have Steve give it the full upgrade treatment.  I think it would make the Pulsars sing and put out a lot less heat than the Pass.  Just another option to consider and best of luck in your search.  Love the Pulsars BTW.  

@boomerbillione As pointed out above, your statement about Pass Labs amplifiers is simply not true. Not only does the xa25 double output power from 8 to 4 ohms, but so does *every other amp they make*.

There are a few First Watt products that put out less power into lower impedances (http://www.firstwatt.com/prod.html) but obviously those are built for special cases where the end user does not need high power and has carefully considered the speaker/amplifier match.