Hi Everyone,

I was just wondering what people's opinions were on the famous (or
infamous?) McIntosh autoformers, i.e., whether you think they are
useful, how they change the sound you hear, et cetera. I've heard some
people say they like the sound of the MC7200, for example, which is a
direct-coupled amp without autoformers.

I have a Mac 2300, Mac 2200 (both have autoformers), and a Mac 2002 (no
autoformers), but have not yet done side-by-side comparisons. It
probably would be most interesting (and fair) to compare the 2200 and
2002, since they have the same rated power, but differ mainly in the
presence/absence of autoformers (2200 has 'em, 2002 doesn't...cue
music..."Almond Joy's got nuts, Mounds don't!")


Thanks, and looking forward to your comments,

Adam

On 4 Jun 2006 19:00:31 -0700, "Adam" wrote:

Hi Everyone,

I was just wondering what people's opinions were on the famous (or
infamous?) McIntosh autoformers, i.e., whether you think they are
useful, how they change the sound you hear, et cetera. I've heard some
people say they like the sound of the MC7200, for example, which is a
direct-coupled amp without autoformers.

I have a Mac 2300, Mac 2200 (both have autoformers), and a Mac 2002 (no
autoformers), but have not yet done side-by-side comparisons. It
probably would be most interesting (and fair) to compare the 2200 and
2002, since they have the same rated power, but differ mainly in the
presence/absence of autoformers (2200 has 'em, 2002 doesn't...cue
music..."Almond Joy's got nuts, Mounds don't!")


Thanks, and looking forward to your comments,

Adam

For those of us who are less "in the know", can you explian just what
an "autoformer" is?

For those of us who are less "in the know", can you explian just what
an "autoformer" is?

As per Roger Russell's website,

http://www.roger-russell.com/mcintosh1.htm

autoformers are output transformers which allow the amp to drive
different loads (2, 4, or 8 ohms, for example) and exploit the full
power rating, without increasing their amount of heat generation.
According to Mr. Russell, they also provide some measure of protection
to the loudspeakers in the case of an amplifier malfunction. Please
check out his website for the full description.

Thanks,

Adam

wrote:

For those of us who are less "in the know", can you explian just what
an "autoformer" is?

An autoformer or autotransformer is a transformer built with a single
winding with multiple taps... you can use it to alter voltage or impedance
like a standard transformer but without getting any isolation.

Lots of companies used to make transformers for speaker load matching, so
you could run 70V systems from transistor amps with 8 ohm outputs, or
you could get more power from an amp that could drive 4 ohm loads by
better matching into an 8 ohm speaker system. For the most part these
aren't used any more, now that we have amplifiers that can put huge amounts
of power into low impedance loads.

Some folks have liked what the transformer matching does to the low end
on studio monitors. Some folks haven't. Personally I think it depends
entirely on the speakers and how they are voiced... a lot of older speakers
were voiced for transformer matching since they were designed for tube
amps, and they sound better that way than with a low-Z source.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."