Para,
I think the 2200/200 is fine to drive surrounds, but it just isn't as polished as its big brethren. It's got a higher noise floor and lower gain compared to the 755/7500. I have listened to the 200 and it just didn't do anything for me as a mains amp. A friend is using several of them to drive 4ohm subwoofers. I don't think they sound very good in that role, but for my friend, they were a big step up from the old Pioneer power amp that was doing the job. I borrowed 2 of them for a few days when I still had my Dahlquist DQ-20i speakers as my mains and they just sounded rather lifeless. However, that wasn't a very fair comparison because my regular amp was an Adcom GFA-5802, a MUCH more expensive piece of gear. That's when I decided on the 755 instead of a pile of 200's for my theater system. For a theater system, where it's just going to drive surrounds (not the mains), it's probably got the right mix of stuff...it's cheap, it's small, and can adequately feed smaller surrounds and you won't notice the lack of soundstage, the higher noise floor, or lack of punchy bass.
But let's compare apples to apples. The 200/2200 is outsourced to a factory in Asia (not the same manufacturer as their other amps) and is probably not made with the same quality of components as the ATI amps. If one of you 2200 owners has the chance, I'd be curious to see some closeup digital photos of the innards of the 2200 to be sure.
Hope that clarifies things a bit. For the money, it's not a bad little amp for what it does. But I certainly wouldn't use it for critical listening on my main speakers. There are better choices for that which aren't a whole lot more expensive that will yield more pleasing results.
Cheers,
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