Re: Decent HTIB under $400
Sony is actually a bit notorious for making bad systems in the audio scene. Seriously, everything from their receivers to their speakers are horrible.
A setup I tried once, that can be had for your price range if you look around, was a Pioneer VSX-816-k and a set of Polk RM6750 speakers. I think I found that receiver for $200 at bestbuy and the speakers were $200 on sale at fry's once. The RM6750 has a silk dome tweeter on the center speaker, so you can get some fairly good details out of it. The subwoofer is weak though, so you won't hear it much if you have a larger room, but it will work fine in a smaller room. The sub also doesn't make use of a dedicated LFE channel, which is also lame. But if you have a larger room, you probably want something larger than satellite speakers anyways and this setup wouldn't work well for you. In fact, nothing for $400 would work well for you.
I returned the whole setup because I was willing to spend more, but for the price it is a pretty good setup. The receiver is a decent low budget one though, so if you ever want it to sound better, over time you can just replace the speakers for better ones. I don't think they make that particular model anymore though, the new version of that one is the VSX-817 I think, and it is in the same price range.
For $400 you aren't going to get HDMI though (at least, not if the setup hasn't cut some major corners elsehwere anyways.) If you want HDMI, you'll need to spend a minimum of $300 on the receiver (this is what I spent on my current Onkyo TX-SR605, though that price is relatively unheard of for this receiver, you can get other HDMI receivers in that range.)
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