Mcintosh 452 vs Pass Labs XA 30.5

Efficiency and impedance loading are two different measurement parameters in a speaker, end of story, your the one with the BS, with the inability to distinguish between the two, to mate amps up with.

For those that are interested:
An inefficient speaker like these Totems with low (80db) and fairly easy impedance load, can still be driven by a mediocre amp with less than average current drive, so long as it has high enough wattage for that inefficiency, to be played loud.

But if that same speaker also had a nasty impedance load as well, then it still needs an amp with the wattage to go loud, but would also need that amp to have good current drive as well to handle the nasty impedance load as well to stay linear in frequency response at those low impedance dips. If not it would sound like a tone control at those impedance dips.

Cheers George

“On these fairly easy to drive speakers, both will work fine...”

Totem Mani2 speakers are actually not an easy load

I beg to differ, you quoted me.
They are an easy load for an amp, just not efficient so you need watts. 

Not looking for an argument but whatever wording you want to choose your advice was not appropriate.

But you are, then don't quote me and then try to "cover" your inability to distinguish "bad load for a speaker" with "inefficiency of a speaker".
A speaker with bad load impedance for an amp, with one that's just "inefficient", which in this case the Mani2's are, just inefficient and NOT a difficult impedance "load" for an amp.

mizioa

The  30watt Pass to me will sound the best to a given volume level, but the 450w Mac will go louder. This volume level has nothing to do with the "load" the speakers presents, but the "efficiency", to which will give the higher volume level. As far as me saying the Pass will sound better to a given volume, that's because it's a Pass, and the Mac? well is a Mac, (a solid state with output transformers?????) bizarre!


Cheers George   
     

Totem Mani2 speakers are actually not an easy load

Not correct.
They are an easy load, they are just not efficient 80.7db, which means they need watts rather current when played loud.
 
https://www.stereophile.com/images/archivesart/Mani2fig1.jpg
" I calculated the Mani-2's B-weighted sensitivity as a very low 80.7dB/2.83V/m. No wonder it didn't go very loud with the low-powered 15W Cary  Cary CAD-300SEI amplifier, as delightful as the sound was."

Cheers George

On these fairly easy to drive speakers, both will work fine, but my money’s on the Pass for a better sound at "normal. And on harder to drive speakers the Pass all the way every day.
But if you really want to get loud with these speakers they are are only 80db efficiency which means you want watts and that’s where the 450w Mac will beat out the 60w @ 4ohm Pass, in being able to go louder, but not necessarily better sounding. 
https://www.stereophile.com/images/archivesart/Mani2fig1.jpg

Cheers George