Yes, agree with ttocs.
McIntosh is one of those makes that vary from model to model and the variance isn't marginal. I'm not sure what it is, whether it's the auto-formers... unlike most well designed SS gear, where their Output power doubles or triples as impedence swing drops, in the case of Mac this doesn't happen. Due to its Auto-former design, whether this is a good thing or bad thing I don't know. Mac hasn't deviated from this Auto-former design since the kookobas came home, and they continued to use it in every power amplifier design to date.
I've tried 100w Mac amps that couldn't drive my former Maggie's optimally (MG3 5/r) or any of those previous Maggie's I had ranging from MGIIIA to MG20.1's. Then auditioned big Mac's driving the ML Neoliths, those were the MC1200 monoblocks, massive amounts of power but not optimal. Then tried a MC462 on the Ren15a's, fine! I guess the hybrids are easier to handle compared to either full range ribbons or stats.
Then a very good mate of mine here had the mighty Maggie's 30.7's (the one and only 30.7's to arrive in Aus). Drove them with his C53 and MC462, didn't work too well. He sold off the 30.7's and just stuck with his Klipsch triple stacked horns, the Mac amps love those Klipsch horns! He's also using the MC452 and another MC301 for the low end, mighty impressive and massive dynamics, plenty plenty of headroom.
On that very same Neolith system, we tried Pass Labs XA160.8, and Momentum 400's both monoblock design, oh my! What a shift in gear! Totally different league!
Also auditioned at length Pass Labs XS300's and Dan D's Relentless monoblocks driving the Maggie 30.7's, completely different dimension, it's not even funny.
So goes to show that it's definitely not all about watts/ power. It's the high current capacity along with highly stable voltage that drives and controls stats optimally. Yes, power is important but what's the use of all those precious watts... when impedence swing drops to less than 1 Ohm (0.7 Ohms to be exact) and suddenly rises to 20 Ohms in a blink of an eye, those watts aren't going to make it. Current and stable voltages are critical to driving stats and this is where the headroom proves worthy.
Most high powered amplifiers simply don't have very well designed power supplies in the Output stages but on specs they look mighty impressive! This is where they run out of puff, especially on the high notes. And with stats, it's the high notes where the impedence drops to less than 1 Ohm, not the bass. Bass makes the impedence rise to over 20 Ohms in some cases, this is referred to as "Reactive loads" and only very well designed power supplies can handle reactive loads typically found in stats!
Oh! I forgot to mention one particular make that's a phenomenal match with ML stats, apart from the ones mentioned above. The Vitus SS-103, phenomenal!
Awe-inspiring experience.
Cheers and enjoy those fine tunes!
RJ