MAC Autoformers?

I would guess that that a Mac with autoformer will sound good => better => best depending on the speaker load. A very demanding speaker load, the autoformer will be of a benefit, therefore, in theory, better sounding. A speaker with a very benign load will sound better when used with a non-autoformer amplifier due to the simpler topology. Or, you can listen to both amplifiers and pick the one that sounds the best to your ears, but that makes for a very poor forum discussion.

If it gives such great benefit why don't other companies use them? It is quite true that transformers are a mature technology so if they gave an improvement in this area it should have been seized on by many of the "cost no object" amplifier designers. Krell , for example, will drive very low impedance loads at least as well as the Mac without transformers. The question here is whether their prime purpose is to improve the sound or protect the amplifier. Since the transformer is the prime weakness of tube designs it is hard to see how it will help SS ones.

I think that the McIntosh autoformer is utilized for a number of reasons. I have had a few amps with and a few without. The ones with sound better than those without, IMO. The cost, weight and size of the autoformer is probably the main reason McIntosh doesn't use them in certain amps. I have found that the non-autoformer amps lose detail and that "tube warmth" and seem to have a brighter less musical presentation, again IMO. The question as to why other manufactures don't use autoformers is probably due to them not wanting to add the circuitry to the output stage. But keep in mind that McIntosh designs their amps knowing they will use it and design with it always in the grand scheme. The non- Autoformer amps have a totally different topography it is not like they just add it to some and not others. I am quite sure that McIntosh realizes that the autoformer causes a level of diminished performance by it's employment. But I think in the overall scheme of things McIntosh builds their products with a few goals: Sound Quality, Product reliability, protection of circuitry and speakers. Maybe they are willing to sacrafice some sound performance to acheive a "built like a tank" amplifier that will provide years of reliable service, and let me add here, that this is my theory not fact. I have bought as mentioned many McIntosh amps and preamps. The one constant in all of these is they always work and they always sell quick and hold the majority of my investment.
McIntosh is not for everyone, but then neither is Chevrolet, Levis, or asparagus. Pubul57, my advice is buy the Mc amp with autoformers. You will receive maximum McIntosh performance and maximum resell when you move on.
If you want the best amp ever made, then spend the rest of your life reading the opinions of audio enthusiasts, myself included, among those found in many many forums. But in the end make your decision must based on 2 things 1)what you hear and 2)what you can afford at the time. This is all of course my OPINION only and I could debate this for weeks on end with those who disagree. But this is what I feel and you must adhere to the 2 decision makers listed above. As a final note, in my years of buying audio equipment and reading forums I can think of no other brand that receives more bashing than McIntosh. I have dealer that bashes Mcintosh all the time but in his secret room it is all McIntosh, go figure. However, I see them holding the some of the best resale values. Do what makes you happiest and enjoy your music the most that you can.

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.