When your bluray player plays back the video, it simply sends a completely undecoded audio file over the HDMI cable to the receiver. This file, whether it be Dolby Digital, DTS MA HD, Dolby True HD, has all of the audio tracks (left, right, center....) as completely separate entities. That is, the receiver does not have to "separate" them from each-other, they are not combined together at all. When the receiver decodes the audio the separate channels are played back on their respective speakers exactly as they should be, every time, unlike old prologic where the receiver was required to split the center and mono surround channels off of a specially encoded stereo signal.
+1 this is exactly correct. Where I would start is speaker placement, better speakers and a much better subwoofer. There are several excellent
articles on speaker placement and getting the most from a subwoofer on the main sight.
The cheapest large room solution, if you live near a Fry's, is a pair a Infinity P363 towers (regular $325ea on sale for $99ea today - in store only), a
PC351 center, and 2-4
P153 bookshelves as surrounds. If you're not near a Frys you can get them for $200ea on
online. So that's $700-900 for a decent 7.0 speaker system (plus sub).
A step up would be a system based on three
Ascend Acoustics CMT-340SE up front and a single pair of HTM-200 surrounds. A 5.0 set would cost you roughly $1200 shipped and you can always add the back surrounds (to go 7.0) later but they really aren't necessary. I've owned the 340s and they are very good for the money.
Assuming a medium sized kitchen you have at least 5000-6000cuft for a subwoofer to pressurize and that's not trivial. I would contact
Rythmik,
Outlaw Audio and
Hsu Research and have them spec you a sub or two based on total room volume but you're probably looking at a pair of $550-600 subs. FWIW subs make nice end tables for the sofa.
Hsu Research also has a couple of package deals on their speakers and subs. I prefer the Ascends but they cost more and the Hsu are pretty good. I'm just not sure about their speakers in a room that large - it might be a bit much for them. And being rear ported the surrounds will be a challenge to place since they need to be at least a few inches from the wall.
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