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Posted By: Pitbull 7.1 Setup and Qs8 placement - 08/31/05 02:48 AM
After researching alot of the posts; what I didnt notice is talk about the distance of the rear placement of the speakers. I am in the process of building the home theater and have waited 8 months for my Axiom setup.

I will be wiring the walls so here is my question. My room is 20x25, theater seats will be at 12 feet and 16 feet roughly. Would I be best placing the speakers in front of the first set and to the rear of the second set? I have read also about placing them at the back wall with at least 4 feet difference. Is there a limit as to how far back the QS-8 should be from the listener in order to produce the sound? Otherwise if I place them in the back wall they would be roughly 9 feet behind the last seat and 13 feet from the first. Thanks for any help and I cant wait for my AXIOMS almost time to get them delivered.

Posted By: JohnK Re: 7.1 Setup and Qs8 placement - 08/31/05 03:36 AM
Andrew, in a 7.1 setup the side surrounds ideally would be directly to the side of the listeners, but especially with QSs, it isn't critical and maybe splitting the distance between the rows of seats would be fine. As to the back surrounds(on the back wall), the distance behind the listeners(as long as it's at least a few feet)also isn't critical and calibration of sound levels and delay will ensure a proper effect at all reasonable distances. The back surrounds should be separated widely enough so that both a left rear and right rear effect can be experienced and in your case 12' might be reasonable.
Posted By: Nat Re: 7.1 Setup and Qs8 placement - 08/31/05 11:41 AM
If you have not purchased the speakers yet, then I suggest that you re-think the need for the extra 2 in the 7.1 setup versus a 5.1. In my case it did not make much difference and I only rarely feel that they add value to my experience. Even in 6.1 movies, there are usually only a few scenes where you will feel the difference.

I suggest that you go for 5.1 and then upgrade to 7.1 only if you need to.

My 2 cents.
Posted By: ratpack Re: 7.1 Setup and Qs8 placement - 08/31/05 12:13 PM
Pit: you might want to read the Axiom August newsletter that just came out yesterday. There is an interesting article by Alan on QS4/ 8 placement.

It might help answer some of your questions.
Posted By: Pitbull Re: 7.1 Setup and Qs8 placement - 08/31/05 02:40 PM
I did read it that is why I posted my question. See it talks about 5.1 not 7.1 and places the QS-8 behind the listener. Well what happens with 2 sets of QS-8s?
- Should I place them behind each listening area (row of seats)
- Should I place one set behind both listeners and at the end of the room
- Should I place one set in front of the first row and behind the first row
- Should I place one set in front of the first row and behind the second row

There are many scenarios here and after reading the newsletter thought I would post this. As for going 7.1 I am looking to the future as I am adding plates for up to 10 speakers anyhow plus fiber cat5e and rg-6. Hence why I thought I would ask the people who might be running 7.1.
Posted By: Capn_Pickard Re: 7.1 Setup and Qs8 placement - 08/31/05 03:31 PM
Pit - I'll give this one a try, too.

If you're set on going 7.1 - why not? It's fun! I have a 7.1 set-up and, contrary, to some opinions, especially with DLPIIx turned on, I enjoy the extra speakers, since there is quite a bit of extra ambient information always on in these speakers.

Regarding placement - try this...

Center channel in the middle. Mains flanking the center, spread out enough so that the soundstage is wide, but nto so wide as to creat a "gap" in the sound (try to create an equilateral triangle between the two main speakers and the main listening position).

Next, surrounds - your main question. You have a couple of choices. You can either optomize the set-up for a single position, or try to spread out the sweet spot a little more to accomodate more listener/viewers and maybe sacrifice a touch in the main sweet spot. If you're going to set them up for a single main sweet spot, then, place the side surrounds ("SS") directly to the sides of that position, maybe just a hair or two back from the listening position. Then, place the rear surrounds ("RS") on the back wall at exactly the same distance that the main speakers are separated. If this is impossible, you can move them in towards each other slightly, but always try to keep some room between them - it helps with rear panning effects to spread out the soudnfield, and also helps eliminate the problem where sound from the rear sounds like it is coming from the front (commonly a problem in a 6.1 set-up with a RS that is direct firing).

If you're going to maximize the sound for all listeners, I would suggest placing the RSs on the back wall in identical fashion as above, but would split the difference between the two rows of seating and place the SSs there. The angle of the QS speakers will provide excellent coverage in this scenario and will actually erplicate the sound in a movie theater created by having multiple side surround speakers lining the walls, playing the same sounds.

As noted above, though - the QS series are very forgiving. Try placing the QSs on a step ladder or high table and move them aroudn the room, experimenting with different seating positions, etc., to see what sounds best to you. Good luck.
Posted By: Ajax Re: 7.1 Setup and Qs8 placement - 08/31/05 03:42 PM
I think we're having a communication problem here.

First, as far as I know, this is physically impossible "Should I place one set in front of the first row and behind the first row." I don't think one set can be both "in front of the first row," and "behind the first row" at the same time.

Second, This also is physically impossible "Should I place one set in front of the first row and behind the second row." Since the first row is the one closest to the screen, if you put a set "in front of the first row," it will, of course, be in front of the second row as well."

The Axiom FAQ states --

"Ideally, surround speakers (these are called 'side surrounds') should be either wall-mounted or stand-mounted to either side of the couch or primary listening area, from one to six feet higher than seated listeners' ears, and slightly forward or rearwards of the listening area if you wish. Axiom's Quadpolar surrounds are especially versatile and can yield excellent performance with stand or wall-mounting to the rear as well as at side locations. (see our dedicated stands for the QS Surround speakers in the Store). Rear surround speakers for 6.1 and 7.1 installations are intended to go on the rear wall at about the same height as the surround speakers."

Based on the above, and keeping in mind that the first row is the row closest to the screen, I'd place the side surrounds on the side walls behind the first row, and in front of the second row, about equisdant from where peoples heads will be in both rows.

The rear surrounds would go on the back wall, which is the wall directly behind the backs of the couches, regardless of how far back that wall is, unless it's in the next county.


Posted By: Pitbull Re: 7.1 Setup and Qs8 placement - 08/31/05 04:01 PM
Rough crowd.... I just missed typing in the second set for both those sentences. Seems my post got deleted while typing and undo wouldnt correct it. Guess I missed out some information after re-typing it. Thanks for the help guys. My biggest concern was the fact that if I was putting the rear speakers too far back.
Posted By: bridgman Re: 7.1 Setup and Qs8 placement - 08/31/05 08:32 PM
My brother-in-law's basement has about 18 feet (and a pool table) between the back of the couch and the back wall. He is being told to go with in-ceiling speakers for rear surrounds but my guess is that conventional rears on the back wall would still be better.
Posted By: Capn_Pickard Re: 7.1 Setup and Qs8 placement - 08/31/05 08:37 PM
Having the back wall separate from the seating will actually improve the rear soundstage. You're lucky if your set up permits you to do this. My couch is slammed right up against the rear wall, so placement of the rear speakers was tricky and makes the effect a lot less, well, effective. To compensate, and disperse the rear surround speakers, I point them up towards the ceiling so I get reflected sound that more closely replicates sound coming from above and behind me. Your set-up is far superior, it seems, to most here, since most of us do not have dedicated home theater rooms with multiple rows of seating and an enclosed "box" environment with many options for placing speakers. It's gonna sound great!
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