"06-05-15: Effischer
It always surprises me when people don't check the manufacturer's documentation that is available online at no cost. The manual for MA5200 clearly states in three places that the MA5200 is designed for speakers with an impedance rating of 8 ohms."
Actually, I did check the manual before posting. Regardless, you're not taking all of the variables into consideration, as well as guessing yourself.
An 8 ohm rating for a pair of speakers doesn't tell the whole story. 8 ohms is an average rating. That means a speaker can present loads to an amp that are higher, and lower than 8 ohms. Many speakers can easily drop down to 4 ohms and below under normal use, even though they are rated for 8. So the reality is, you can have 2 pairs of speakers both rated at 8 ohms, and one may be difficult to drive, and the other easy.
"The German magazine found exactly what would be expected for output into a 4 ohm load, but because Mc doesn't explicitly state output values into 4 or 2 ohms as they do for other products, the amp section likely becomes unstable those average loads. In short, it will work but will get hot and eventually distort the signal. Mc makes a terrific product line, but this is their entry-level integrated."
Given that information, I think the opposite is most likely true. First, you have the German magazine that found the amp does double its power under a 4 ohm load. Most amps can't do that and still have a clean signal with low distortion. Second, McIntosh states the amp is rated for an 8 ohms speaker, and that's it. No restrictions are listed. They know full well that most 8 ohm speakers, at times, will drop down to 4 ohms and below. That implies the amp will be able to drive any 8 ohm speaker, even the difficult ones. You can even have a situation where an 8 ohm speaker is more difficult to drive than a 4 ohm speaker.
Jimmymac,
What kind of speakers do you have? Maybe one of us has some experience with them.
