What is the minmimum room size for Magnepan?

The 1.6's sound best at least 5 feet away from the rear wall and at least 2 feet from the side walls (preferably 3-4 feet). You should sit at least 10 feet away and 15 is about the right distance for me. All these distance vary of course per personal tastes but, you get the idea. I have 1.6's and the tweeters are fine and going on 2 years old. I do not know about them falling apart but, I have heard a little about the tweeter being fragile and my own tests have proved that wrong. I played an Innersound amp that had 1000 watts into four OHMS and you would not believe how loud those speakers get. I do not think you could damage them except with 'bad' power.

I believe most people think the tweeter/midrange panel is at their limit but in fact it is the power amplifier that is running out of power. Clearly this was the case when I had the Innersound amp like I mentioned in the above post. Even with my Plinius SA100 MKIII with about 175 watts of class A power (into 4OHMS) these speakers are not even close to playing as loud as they could go with the Innersound amp.

It is true that speaker placement in the room varies (of course) but, the point I was making if you really want the 1.6's to 'sing' you will want a big room. If they get too close to the back wall they become 'thick' and lose definition in the bass, if they are too close to the side walls they will get a blare in the midrange.

That is my experience and I know I do not have as much experience as some but I am very diligent in my accessments.

I do not think my Plinius has enough power with 175 watts into 4 OHMS, I would guess around 400 - 500 watts with a lot of current would max them out.

I know this sounds like a lot but I would like more power with my setup, and the Innersound setup never sounded strained at all with 1000 watts, so somewhere in the middle is my guess.