MAC Autoformers?

I am pretty sure that MAC had or has a patent on the autoformer. It is expensive to manuf. I have had both.
I would not refrain from a MAC purchase because it did
or did not have them. They do put them in their more expensive equipment. The autoformer does keep that sweet MAC sound with all loads. MAC's without autoformers do not have problems with loads either.

I would not call them degrading.....I saw the ad the poster
was referring to.........it is an ad. I would not give the same opinion. I have sold a few amps that were more powerful to the ear and went back to MAC.

Oh Boy! This is an old argument, and when it pops up, you invariably hear someone say that Autoformers add distortion, decrease detail etc. It is all nonsense. The proof is in the sound, and the amps with Autoformers sound fuller and more effortless and authoritative (to me) than those without. Bottom line, the "Mac Sound" is best expressed in the amps with Autoformers, and it's a great sound, so if you are going to get a Mac amp, I would say get one with Autoformers.

Different circuit designs accommodate different components. To say any amp is good or bad based on the fact that it has either transformer or direct coupled outputs without listening is just a foolish generalization.

I have used many Mac amps over the years (since 1978) except for the latest models, whose prices are truly hideous! My conjecture is the same as ONTJESR, the 7200 was/is the best amp they've made, and with no autoformers.. In my experience, all the autofromer models had a "flabby, not tight" bass. The 7200's bass is deep and tight. I always thought what most of you express, if they're so great, why don't other manufacturers use them? Mac claims it lets them match the loads to any speaker impedance. I own the 7200, and have yet to hear the un-tube-like sound some of you claim to hear. This is their best amp I've heard! THEO says it about right!

The reason I though the autoformer was a good thing is that my speaker manufacturer (Merlin)suggested that if I want to add an SS am (I own two tube amps that I switch around)to consider the MacIntosh with the autoformers, which is interesting in light of some of what has been said here in that they have a very easy load and very smooth impedance curve, where the autoformer would seem to be less needed. Well I think I'm going to decide based ergonomics and not worry too much about the AF/non-AF issue. Any opinions on differences in sound quality, or other considerations between the 6300, 6500, and 6600. Power is not an issue, my speakers run perfectly fine on 50 watts or more.