How much Power for Maggies 3.6 is enough

Whoa, dangerous topic. It depends on how loud you like to listen, after all, 1000 watts is only twice as loud as 100. If you want to play Mahler at front-of-the-orchestra levels without clipping, you need that thousand watts. Even then, you can't quite capture the peaks of the loudest acoustical music. However, the ear will tolerate some clipping, particularly with tube amps, and most unamplified music is not this loud even at natural levels. We're talking about true instantaneous peak levels which are about 10 dB higher than what you'll measure on a Rat Shack, if you played pop at these levels you'd ruin your ears. As a general rule, tube amps only need to be about half the size of a transistor amp. Hence the fact that you'll find some people recommending 50 watt tube amps, and some recommending 1000 watt solid state amps, and neither are wrong -- for them.

Josh358,
Great point and well said.
And, as always, 'how loud' is a personal matter.
Loud to me, used to be moderate to some and so on.
Another Jim Thiel quote here...
One time during a seminar, someone asked Jim..(at my store)...
"Mr. Thiel...all things being equal, would 200 watts be better than 100 watts."
Talk about flummoxed...Jim stood for the longest time...contemplating, with that look (if you knew him, you'd know, 'that look').
'Well, things are almost never equal, but yes...'
The questioner started to sit...
'But then, 10,000 watts would be even better...' Smile...

I suppose you had to be there, but it was hilarious...Jim never TRIED to be funny but, DAMN sometimes he was a scream...this was one of those times.

Good Listening,
Larry
'

Onemug,
how did the McIntosh and Krell amps compare to your current XA100.5s?

Hasse,
The Mac (from that generation) was sweet and easy to listen to, nice midrange. The KSA 250 was one of the most powerful sounding amps I've ever had and I thought better than the Mac overall. The 100.5's are my favorites. Low level detail is beyond the others, sweet class A midrange and a non fatiging high end. Interesting thing on the MC1000's, even with all that power, they lost what I liked about them as I turned the volume up even though I was well below the 1000 watt mark. But most of my listening was at the .5 to 50 marks on the meter so it wasn't an issue. The Krell and Pass kept/keep their sound as the volume went up.

How big is your room, how 'damped' is the room, and what is a typical listening volume for you in db?

Short answer; the more watts and current, the better with all Magnepans. I use Cary 500 MB with my 3.6's and have been very pleased with the results. My room is 17.5 x 26 x 9. Typical listening volume is in the range of 75 db - 87 db. I seldom get to 90 db.