I joined this forum specifically because of a previous post in this thread which I came across looking for bench tests of the 462. This March audio amplifier is nowhere near a competitive product to the 252, which is a great and well loved amplifier but has been out of production for quite some time. It is going to be substantially superior to this 502 amp which they are very hush hush about specification wise. Since it is class D it is going to have some impressive numbers but nothing to back it up. From the previous posts
- An early post said something along the lines of "the amplifier has the same output at 2,4,8 ohm? I find that hard to believe" -what I find hard to believe is that anyone who is in the audio business does not understand what the impedance matching transformer (autoformer) does. McIntosh has been using this technology for decades. A later post says "and not at the same distortion" and again, yes, that is the purpose of the device. And it has many other benefits. That class D amp is not going to have this kind of technology and that's just the first of many
- The one that captions sentry monitor and power guard- again, the user does not understand what these mean or do. Powerguard is one of the main reasons to get McIntosh, it's a voltage comparator that reduces the volume if there is distortion and does so until there isnt. This is because even if you can't hear the distortion it will easily damage tweeters.
- The class D amp specs are given with no tolerance or with no details. In another post it is mentioned that they test at 1k hz. This is a dead giveaway that this is not a high end piece and it is the total opposite of the McIntosh philosophy of conservative design. As a responder mentioned the Mc amp is giving the theoretical worst case, while the class D is giving you perfect condition best case.
- Dynamic headroom-don't even try on that one. That class D amp will not have it, and even if it did you wouldn't be able to use it.
- McIntosh reliability- they will always stand behind it. Period. Once this class D goes out of production parts will be unavailable quickly.
- In summary- In both real listening tests and in meaningful tech specs, the MC252 will absolutely wipe the floor with that class D amp. They aren't even in the same class (pun intended).
- Look at the value on the used market of the MC252, long out of production, vs two of these class D amps brand new. And the 252 takes a hit on value because of the notch.
The only reason you would ever want to use a class D is if, for some reason, you had space or weight limitations, or for a subwoofer. A quad balanced 462 amplifier VS a class D amp? There is no comparison. Absolutely none.
How McIntosh does things:
250W at ANY frequency, from now until we are all dead, and well below our specification for distortion. Dynamic headroom is pretty much code for "this amp will do x dB overdrive" so that's why they always bench way over the spec.
What I read on that Class D amp:
We got one to do 350w on a bench, probably at 1k, and possibly with one channel driven, and at unspecified distortion. We picked 350w and so we used it. Don't run it that hard though, because it'll clip. Which you shouldn't do.