What are the speaker placements for 7.1 HT setup?


Dear list,

First and foremost, a great thanks in advance for all
helps in all forms.

I'm in the process of setting up a separate multi channel
audio system for HT. I have acquired the following
equipment for the purpose that fits my budget and taste.

1) Sony DVP-NS999ES DVD player.
2) Mcintosh MX134 pre-amp/processor
3) 3 MC1201 monoblocks.
4) 2 MC602 stereo amp.
5) Monster THX 1000 cables.

I haven't committed any plunder I hope?

I'm in the process of speaker selection for above setup.
Now, the MX134 is capable of 7.1 surround processing, how
many center speakers do I need? What are the correct speaker
placements for 7.1? Do I have a rear center? Is 7.1 better
than 6.1, why?
kee_tan
Kee_tan

My comments are focused on the question of a 5.1 vs 6.1 vs 7.1 speaker system.

My recommendation is to go with a 7.1 speaker system, unless you have a physical layout that just will not support 7.1. If you cannot do 7.1, then I recommend 5.1. I do not recommend 6.1. The general layout for 7.1 speaker placement is a guide. The best implementation in your particular room can vary.

If you do decide to go 7.1, and want to maximize the 7.1 listening experience, then I further recommend you have surround processing that can generate 7.1 outputs from the various input sources available (2.0, 5.1, etc.). This is needed, in my opinion, because:

- There are no 7.1 sources available at the present time

- You do not want to simply duplicate the surround information in the side and rear channels

The two best choices for 7.1 surround processing are Dolby Pro Logic IIx (DPLIIx), which is available on a variety of receivers and PrePros, and Logic 7, which is available only on Lexicon products, some/all Harmon Kardon receivers, and I think a JBL PrePro.

Dolby Pro Logic II (DPLII), the predecessor of DPLIIx, will only generate 5.1 outputs. If you are using a 5.1 speaker system, then DPLII is fine, but if you use a 7.1 speaker system I highly recommend DPLIIx instead.

Thanks
Bruce
The point of my exercise, which has been blessed by the
numerous contributions from you fine gentlemen (of which
I'm most grateful) is the following;

I have contracted the professionals to design and build
a dedicated none commercial theater as an extension to
my existing home. And the contractors have with the aid of
variety of services provided by their networked
consultants at their disposal, constructed a semi-buried
enclosure of the dimension (in the imperial unit) 45 feet
wide, 60 feet long and with a floor that inclines towards
the front resulting in the maximum height of the enclosure at 19 feet and the minimum at 9 feet. The inclination
stretches both direction from the middle, hence leaving two flat levels at the back and in the front. The size of the
front level ground is 45 feet wide, 40 feet deep and 19
feet from ground to ceiling. The size of the rear level is
again 45 feet wide, but 6 feet in lenght and 9 feet in
height. The seating area (the inclination) measures at
14 feet in horizontal length, composing of 3 sitting rows
each accommodating 5 separately reclinable chair. The
complete SLOPE length (not horizontal) of the sitting
area is 17 feet, the height difference between the last
row and the first is about 10 feet. The sitting allevation
from the one before is about 3.3 feet when upright, 1 foot
when fully reclined. The space in between each sitting
row is about 2.8 feet when upright, 1 foot when fully
reclined.

Now the entire conclosure including ceiling and floor is
completely padded with sound proofing material. There is
nothing protruding, except the (rather cumbersom)
crt projector --barco Reality 812-- attached to a sliding
rail, lighting is purely yellow down light completely
hidden in their respective enclosure.

Back to my task at hands, above contruction is completed,
I have on loan (from dealers) few set of speakers, they
are ;

From Wilson Audio
=================
Watt/Puppy full size --4 pairs
No center speaker, the dealer advises me upon the actual
fact that I should have exactly the same speakers all
round given my current theatre design.

From Dyaudio
============
Dynaudio evidence temptation --3 pairs
Dynaudio evidence center --1 pair

From B&W
========
803D --3 pairs
HTM1D --1 pair

My paid professional services are
more than willing to accomodate me while
discharging their duty to explore ALL
possible combinations in its entirety so that
I, as the paying customer could arrive at the
point where to add or remove, to pivot or turn
will result in no gain in sonic performance but
only degradation! But they can't help me to decide
what I like, I have to make that decision my self.
These are mostly music speakers I might ad. Which is fine for some applications, but not a big space like you're using! May I suggest some more high end "active", higher efficiency focused designs better suited to your HT applicastions?
I've sold WATT Puppies and B&W's over the years, and have some experience with Dynaudio. There are simply better MORE EFFECTIVE choices for what you're doing IMO.
You might consider some "ACTIVE" speakers from a company called AVLAR located in Southern CAlifornia. They''re very high end sounding speakers, that are much more dynamic, focused and powerful sounding than the more passive speakers you're mentioning above. They dynamic realism and pressence will be much more cinema like, and yet still remain "audiophile" grade in refinement!...just a suggestion.
The traditional Stereo speakers you're looking at won't DELIVER THE GOODS for a high impact HT. I know this from 20 years and 6 high end audio stores worth of working experience...not to mention I do custom thaters myself, and am a consumate audiophile tweak myself.
Anyway, it's all good...it's just that some choices are much better and effective for your task.
Anyway, good luck-----------------------------------------
I'm with Hbarrel...maybe we could just camp out in the yard or volunteer to run errands for kee tan....Interesting comments from Flrnlamb about speakers...Avlar? hmmmmm