5.1 - sound is distributed through 5 speakers; front, center, rear and subwoofer
6.1 - sound is distributed through 6 speakers; 2 front, 1 center, 2 rears, 1 surround back speaker and a sub. The surround back is usually a matrix of the rear to give a "wrapped" sound.
7.1 - sound is distributed through 7 speakers; 2 fronts, 1 center, 2 rears, 2 surround backs and 1 sub. Depending on the encoding of the source material it is usually matrixed from the rears again. But some are actually encoded with separate signals for the surround rears, but there not that many, much like 6.1.
Thanks Berny. That helps, so even if I get the 7.1, and all I have is 2 fronts, 1 center, 1 sub, and 2 rears I'm good to go right. I just think with my old pro logic dennon AVR 800, im not getting the best sound that I could be getting
I don't like to break up a good start to this but Dolby 5.1 has been misinterpreted with the common belief and idea that the surrounds should consist of two surrounds for the back and one for each sidewall is false!
The whole purpose of surround is to surround the room! Thou there may be outputs on the AVR or AVP to deliver more surrounds than there are for the fronts which is a shame. What ever happened to the good ole five-screen array!
Costs of installing surrounds in the home needs not to be expensive and with the right planning and execution of the installing of multiple surrounds down the sidewalls and rear wall just like it's done in the commercial cinema.
If you where to take a look at all the different cinemas that are around you'll see that the size of the auditoriums differ. Yet the same amount of surround loudspeakers are still used to create one purpose to surround you know matter where you are seated the atmosphere and artiness of the surround mix will always be as impressive no matter which film you watch.
You have to have a more expanded mind on how your going to design the multiple surround array in you home. Where I have practically gone to the limit of installing some far x8 JBL control 1 for the surrounds, it's quite mind blowing and thou I still have a further x8 more to install for the horizontal plan in room and few more fitted to the ceiling for height surround x10 in a diamond configuration!
I'm thinking about a few more placed on the back wall high above the usual x6, a further x6.
This should take the surround array to a staggering x32 JBL control 1!