Ok, from what I have been looking around, 7.1 sounds like what the old pro logic setup use to be b4 dolby digital 5.1 came out...meaning...7.1 is actually 6.1 when it comes to power. Maybe I just need someone to explai n it better to me though, but all channels are independent? but..the side surrounds tend to share the same power supply? I am sure this is only true for sub 1k systems as you would actually control it better via separates.
The Front, Center, Sides are all Independent And the 2 Surround Backs (SB) Are Not, They Both Share the Same "Channel" You could Say, When Equilizing The System they can Only be Changed toGether, So like you said 7.1 Is Really 6.1 When it comes to power. Hope this Help, Write back if it doesnt!
Uuuh, not really. All the 7 channels are independent, they have their own discrete amplifier transistors and everything. With PL2x there will be different signals on every channel, but they are of course out-matrixed from the surrounds of the 5.1 signal. PL2x cant really do 6.1->7.1, but all 6.1 streams are compatible with 5.1 (surround-back info on surrounds also). When playing a 6.1 DTS-ES or DD-EX without PL2x with a 7.1 speaker system the two surround-back speaker will play the same thing.
What's confusing you guys is that there's no main-stream media formatted for 7.1 surround.
You are picturing 5.1-EX, that is where the surround channels are copied to the rear channels. 6.1 as landroval said, take the rear channel and double it into two seperate channels.
When a DVD is released in 7.1 DD or DTS compatible receivers will play 7 distinct channels. Front right and left, centre, surround right and left, and surround back right and left.
...not currently, but won't the industry move in that direction eventually? So far just a handful of movies are in 6.1 DTS (Rush Hour 2 for ex.), which has 6 discrete channels right.
So what type of decoding would a 7.1 audio DVD use?
6.1 DTS is actually DTS-ES and as you know it needs a more sophisticated decoding hardware. I believe the new DD+/DTS+ (or whatever they are called) will support discrete 7.1 sound, but it will not be possible to decode the 7.1 sound with current decoders. Also we might see the new formats only on HD-DVD and Blue-Ray and not on DVD-V.