How many recordings/movies do you have with 7.1 tracks on them?
This is a great example of where quality trumps quantity every time.
I've set up some viewing rooms that, given the configuration of seating positions, having four speakers in the back was nice . . . this mainly made it possible to get more consistent coverage over all of the seats. These were all rooms "set up the short way", that is, with the screen on the long wall.
But usually, it's easier to get optimum placement with two rear channels as opposed to three or four, and as we all know, placement makes all the difference in the world. Not to mention that if you use half as many, then you have twice the budget for each one . . . which in loudspeakers can be quite handy for improving the sound.
Kal gets to the heart of it when he asks how much 7.1 material you have. If you largely watch Direct or cable you are only getting 5.1 anyway.
For me your question is room related. Strictly speaking, 5.1 places two speakers about 2/3rd way back the room on the sidewalls firing across the audience at each other. 7.1 adds a pair of speakers on the back wall firing across the audience back towards the screen. (draw this out, its simpler to see it then write it)
7.1 gives the sound designer the added ability to work back to front as well as side to side.
If your room is long so that your seating position is at least a few feet off the back wall and a few feet in from the side walls, chances are that the 7.1 would be a nice upgrade especially if you have a very big screen and are after a real theatrical experience.
If like most of us you are struggling to get some distance from the side speakers or are already mounting your 5.1 speakers on the back wall, it's probably not going to be much of an improvement.
Very good information from all. I am trying to figure out why than electronic businesses would make a 7.1 receivers or processors and 7.1 multi-channel amps if there are no DVDs made for a 7.1 configuration.
You ever notice when you sit in a movie theater and don't really hear all the surround speakers working in 7.1 configuration. The transition on the surround speakers just move very smoothly at all. I just hear sound coming out but it does not match what I seeing on the big screen. I just hear mainly on the front of the stage.
The smoothness you hear is the result of the extra speakers - effectively as an effect through some part of the room, each "move" is a smaller increment so the change of speaker location is not as pronounced.
Very often those speakers are not used for panning effects but to provide extra ambience - you are inside a sub - you don't really notice it but it colors your impression. Just as a subwoofer does when its not thumping away doing dinosaurs and bombs.
AVR makers are producing 7.1 in anticpation of future Blu Ray Disc 7.1 production. So far, there are only about 25 BDs w/ 7.1 and about 10 HD-DVD (and there won't be anymore of those).
If BDs really catch on as a consumer preference over SDVD (so far, they have not), I believe eventually all BDs will be 7.1.
Just because there isnt technically 7.1 material doesnt mean you wont benefit from its use, in a larger room the extra speakers and matrixed info does make for a better and more exciting experience. What size room has more to say about the proper choice than anything listed here so far IMO. I have 2 surround systems, 5.1 works best in living room but 7.1 works best in my man cave, its all about size.
>I was wondering if there is a huge difference between using a 5.1 or a 7.1 speaker system?
If you're not using dipole side surrounds and have processing (like Lexicon Logic 7) which intelligently routes the surround channels from 5.1 and Dolby Surround mixes, it's a quantum improvement in immersion. Not quite as significant as going from a good stereo pair with a Dolby Surround track (or down-mix) which extends out nearly 180 degrees to 5.1 but still substantial.
Simple Dolby Digital THX-EX or DTS-ES isn't that interesting. A few sound tracks put a few effects right behind you.
Dipole side surrouns get most of the way there except for the THX-EX/DTS-ES tricks.
It all depends on the size of your room and your seating position. If your room is large enough to benefit from 7.1 and you can place surrounds speakers BEHIND you as well as on the sides, then it would be worth it.
There are increasingly more Blu-ray discs coming out with 7.1 soundtracks and there is no harm in future-proofing.
If you have a good processor, even 5.1 soundtracks would some more immersive with a 7.1 set-up. But if this going to break your bank or you expect to listen to 7.1 soundtracks almost exclusively anytime soon, then 7.1 is probably not right for you.
One thing is that if you starting from scratch and building the system into your room, might as well add cabling for those "height" channels that will be above the left and right fronts for the under-development 9.1 Dolby and DTS formats!
In five years, 5.1 will be history and the topic of this thread will be "7.1 vs. 9.1".