I have a similar problem only i cant put my speakers behind the screen. I don't even have a screen. Just a rear projection TV that i have flush mounted in the front wall.


Due to the size of my room (16.5 x 11.3 ) my speakers are shoved in the corners So they are close to the side and front wall. I tried moving them out just to see what difference it made and i couldn't really tell any difference at all But im no expert either so wouldn't know what to listen for anyway.


I like the sound of the speakers far apart. It really separates the sound to the sides and is great for movies i think.


Just my 2c

 

Thanks for commenting.

 

For movies - I would think having the L/R speakers inside the screen frame is actually proper. I am going to have the same issue with my new room as there won't be enough room on one side to get a speaker outside the screen.

 

Quote:

Originally Posted by Luke_Y In the final planing stages for my construction and have come to a question on the best placement of the front speakers. The room will be about 13' wide and the screen will be about 100"-105" wide. The primary seating will place your head about 12'-13' away. I plan to use an acoustically transparent screen so center placement is not an issue. The question is to the placement of the front L/R. if I place them behind the screen the separation angle as it relates to the seating position will be somewhat narrow, even if I place them toward the outer edges (even worse for the 2nd row). If I move them outside the screen I can come much closer to an optimum separation angle. But... In a 13' wide room that places them right next to the side walls. So, with this room strictly for movies-no music (except for the music in movies), wich situation would be worse for the movie experience? The narrow angle or the problems associated by placing speakers too near the side wall? Could the negative affects of placement near the side walls be mitigated by some room treatment? When I first envisioned this I liked the idea of all the fronts behind the screen, but am afraid I will have to move the L/R out to get some separation. Otherwise I fear it will sound like one speaker back there. Looking forward to your input.

Hi Luke,


What type of main speaker do you plan to use? If they're not In-Wall you should be able to experiment with placement.


Placing the speakers near the side wall will increase Speaker Boundary Interference Response (SBIR) which is a phenomenon caused by the constructive and destructive interference between the low frequency direct sound and reflections at the listening location. Since we're dealing with low frequencies it would take a huge amount of aborption placed at reflection points to mitigate the notch created in the frequency response. (While both phenomenon are a form of comb filtering distortion, this is different than the common practice of placing a modest amount of aborption (about an inch) at reflection points to deal with early higher frequencies to improve imaging.)


Here's some discussion of the topic.

Speaker Boundary Interference Response (SBIR)


Start reading the link above, posting #171, to posting #187. In these discussions, based on measuring the difference in distance between the direct sound and the reflected sound, Terry describes how to calculate the frequency that would experience a cancellation, i.e., a null at the listening location. If the speakers are placed far enough from the side walls this frequency can be lowered so that it is below the crossover points of your main speakers, thereby mitigating the problem. However, generally these distance are quite large, and therefore compromises in speaker placement are usually required.


Larry

 

Quote:

I plan to use an acoustically transparent screen so center placement is not an issue.

Hey Luke, sorry for the thread derail but where are you getting this screen material from? This is something I'd like to try out in my theater being that it's so small.

 

Your front speaker should be spaced appoximetely 45 degree's to 60 degree's apart to establish the proper sound field. It appears if you place your mains behind the screen, they may be too close together thus sacrificing sound envelopment.


To avoid SBIR (speaker boundary interference response), the speakers distance from each surface (back wall, side wall, floor, ceiling) should be radomized. In addition, acoustic treatment on lateral walls to absorb first order reflections will greatly decrease distortions.

 

Now that I look at my layout - I may be in trouble too.

 

Quote:

Originally Posted by Marc Ye Your front speaker should be spaced appoximetely 45 degree's to 60 degree's apart to establish the proper sound field. It appears if you place your mains behind the screen, they may be too close together thus sacrificing sound envelopment. To avoid SBIR (speaker boundary interference response), the speakers distance from each surface (back wall, side wall, floor, ceiling) should be radomized. In addition, acoustic treatment on lateral walls to absorb first order reflections will greatly decrease distortions.

Hi Marc,


Yes, you make a good point about the speaker spacing for proper soundfield.


However to clarify regarding SBIR, locating the main speakers different distances from the room boundaries, while recommended to minimize the reenforcement of nulls at the same frequency, won't avoid Speaker Boundary Interference Response. It will create three less pronounced nulls at different frequencies at the listening location. The application of typical thickness acoustic treatments on the walls to absorb first reflections will greatly decrease high frequency distortions that adversely effect imaging, but it will have little effect on SBIR distortions on bass response.


Luke:

My home theater is 15' wide. I knew I would be going with a non-perforated screen, but I wanted to get the largest image I could and still fit in my floor standing main speakers on either side with adequate space from the side walls. My speaker manufacturer recommended a minimum spacing from the side walls of 3'-4' and a close placement to the front wall, a few inches. I ended up compromising on audio considerations in favor of a larger screen. My screen is 120" diagonal, my speakers are centered 13 feet apart and my first row is 12 feet away. The speakers are about 1.5' from the side walls. I have no regreats, but bass response would have been smoother if I could have maintained a greater distance.


If I had the luxury of going with a perforated screen I would have gone bigger to at least 135" diagonally. Then I would have experimented with the speaker spacing, but not going less than about 10 feet apart.


Larry

 

Hi all, Thanks for weighing in.


First to answer questions;


Larry:

Quote:

What type of main speaker do you plan to use? If they're not In-Wall you should be able to experiment with placement.

The design calls for in-walls. I am planning for Triads the exact model depends on how much money construction burns through.


Ron:

Quote:

Hey Luke, sorry for the thread derail but where are you getting this screen material from? This is something I'd like to try out in my theater being that it's so small.

So far the Vutec Soundscreen is my primary consideration. I got to view one at someone elses home and was quite impressed. If the budget is tight after construction I will probably build a DIY with the Danzian CC until I can afford better. If money isn't tight I may look into Screen Research but I don't know if I could justify the cost over the Vutec.


Marc:

Quote:

Your front speaker should be spaced appoximetely 45 degree's to 60 degree's apart to establish the proper sound field. It appears if you place your mains behind the screen, they may be too close together thus sacrificing sound envelopment.

Not really a question but does hit the point as to my problem, probably more clearly than I put it.

Quote:

To avoid SBIR (speaker boundary interference response), the speakers distance from each surface (back wall, side wall, floor, ceiling) should be radomized. In addition, acoustic treatment on lateral walls to absorb first order reflections will greatly decrease distortions.

The design wont really allow for placing the R/L different distances from the side walls (further on that below). But yes I do plan to treat the side walls to absorb first order reflections.


Back to Larry:

Quote:

(SBIR) which is a phenomenon caused by the constructive and destructive interference between the low frequency direct sound and reflections at the listening location. Since we're dealing with low frequencies it would take a huge amount of aborption placed at reflection points to mitigate the notch created in the frequency response.

How low are the freq. you are referring to? The speakers will be crossed at 80hz, I take it there will still be a problem? Is it the sort of thing I could address with EQ'ing the low frequency response? I plan to have to address this anyway as sub placement is non negotiable ( side of room at about 2/5 built into recessed millwork cabinetry- holding the rack as well).


Now to elaborate overall;


I am not pursuing perfection, but would like it to sound as good as possible given my design constraints.


The front wall will be standard construction with the screen area recessed about 4 inches (sort of shadowboxed). The recessed area will be about 6 inches larger all the way around than the framed 105"w screen thus allowing for a slight upgrade in screen size if desired at a later time.


This only leaves about 1'6" to either side of the recessed area (13' wall) for mounting the speakers if I mount them outside the screen approx. 11.5' apart. As you can see they would be right next to the side walls. But mounted inside a 105" screen they would only be about 7-7.5' apart.


This whole project is an excercise in compromise. The HT is just part of finishing a 1500sf basement. The final authority on many interior design questions fall to my wife. Don't get me wrong, she is very supportive of a large screen front projection HT, with a riser, HT recliners and all... Just not allowing of many of the interior design choices that many of us would make for our perfect dream HT


I think I will have to mount them outside the screen and deal with the consequences as best I can. Larry, I am encouraged to hear that you have no regrets with your R/L 1.5' from the side walls.


As a thought, I could probably build the front wall with a slight bit of angle in from the sides (sort of toeing in the R/L a bit) if that would help. Or would that just create more problems/complicate things further? I would just as soon leave it flat in case years from now technology (at my price point) alows for a much larger screen. In that case I would cover both the recessed area and the speakers to the side with screen.


Thanks for the input/insight.

 

I have a similar situation, but my room is a bit longer at 24 ft. What I did was to make a closet which houses my subs and front staging speakers. The wall which faces the viewing area, is where my transparent screen (perm wall) is and all around the screen I have it covered with acousticly transparent material. This allows me to separate the speakers further from each other.

 

So I am no expert in this field, but I have played with this a fair bit in the past few rooms.


I feel that for movies the 45 to 60 degree recommendation is moot. Movies mixed for digital surround are not using the front speakers to create a stereo image. Rather sound is routed to each discrete channel in a much more flat way. This is a good thing. It makes it much easier for us to get good sound at a variety of locations, not just the sweet spot. Honestly, I prefer tighter placement on the front speakers as long as they are perpendicular to the front wall. This is probably because if you space the speakers too far apart you don't get a smooth front sound stage, but 3 pieces. I would think SBIR will probably cause more problems given all the efforts we go through trying to control bass.


Here is something to try. Put on a nice symphonic sound track and shut off all your speakers except the R&L. Now sit in the sweet spot. You should notice that you don't have a very good sound stage, more like sound on the right and sound on the left. Next try adding in one speaker at a time and listen to the sound stage take shape. They try the same thing for a less desirable seating position.

 

Quote:

Originally Posted by Luke_Y Quote: Originally Posted by Marc Ye To avoid SBIR (speaker boundary interference response), the speakers distance from each surface (back wall, side wall, floor, ceiling) should be radomized. In addition, acoustic treatment on lateral walls to absorb first order reflections will greatly decrease distortions. The design wont really allow for placing the R/L different distances from the side walls (further on that below). But yes I do plan to treat the side walls to absorb first order reflections.

Hi Luke,


Marc meant positioning each main speaker so that the distance from the bass driver to the floor, ceiling, side walls and front wall are all different. When you place an In-Wall speaker in a wall you eliminate one dimension in which SBIR is a problem. That leaves the other two dimensions. If you end up locating the bass driver 1'6" from the wall, don't locate it 1'6" from the floor.


Quote:

Originally Posted by Luke_Y Back to Larry: How low are the freq. you are referring to? The speakers will be crossed at 80hz, I take it there will still be a problem? Is it the sort of thing I could address with EQ'ing the low frequency response? I plan to have to address this anyway as sub placement is non negotiable ( side of room at about 2/5 built into recessed millwork cabinetry- holding the rack as well).

Yes, I would think that equalization would be required, but when we place our bass drivers near a wall we're dealing with correcting both the modal responses, which are being more forcefully energized, as well as the SBIR effects on bass response. The lower your bass driver goes, the less practical it is to move the speaker away from the walls. In the case of your subwoofer it would have to be moved so that the first SBIR notch in the frequency response was less than 20 hz. More than likely that would require you to place it more than 13 feet from a side wall, something that's impossible in your room.

Quote:

Originally Posted by Luke_Y I think I will have to mount them outside the screen and deal with the consequences as best I can. Larry, I am encouraged to hear that you have no regrets with your R/L 1.5' from the side walls. As a thought, I could probably build the front wall with a slight bit of angle in from the sides (sort of toeing in the R/L a bit) if that would help. Or would that just create more problems/complicate things further? I would just as soon leave it flat in case years from now technology (at my price point) alows for a much larger screen. In that case I would cover both the recessed area and the speakers to the side with screen.

Going to the added expense of buying a perforated screen may not give you your money's worth if you're only concealing the center channel. If your projector and ceiling height permit it, you may want to consider increasing the size of your screen to get more WOW factor. On the other hand, regardless of the size of the screen, having an acoustically transparent, perforated screen would have some acoustic benefits versus an acoustically reflective non-perforated screen.


If you went with a larger perforated screen, depending on the size you might end up placing your main speakers in the real front wall. Then the issue of angling the "false front wall" would be moot.


Larry

 

Quote:

Originally Posted by Luke_Y Larry, I am encouraged to hear that you have no regrets with your R/L 1.5' from the side walls.

Hi Luke,


Correction:

This is perhaps a minor point, but instead of going by my faulty memory, I measured the distance. My mains are approximately 24" from the center of the bass driver to the side walls.


Larry

 

Quote:

Originally Posted by sbraab I feel that for movies the 45 to 60 degree recommendation is moot. Movies mixed for digital surround are not using the front speakers to create a stereo image. Rather sound is routed to each discrete channel in a much more flat way. This is a good thing. It makes it much easier for us to get good sound at a variety of locations, not just the sweet spot. Honestly, I prefer tighter placement on the front speakers as long as they are perpendicular to the front wall. This is probably because if you space the speakers too far apart you don't get a smooth front sound stage, but 3 pieces. I would think SBIR will probably cause more problems given all the efforts we go through trying to control bass.

I agree. For whats its worth I have all my speakers behind the screen which would make the L/R about 8' apart. I sit at 11' from the screen, 2nd row at 16'. Movie soundtracks do not lack any separation at all and the front soundstage is seemless. For example if a car is driving across the screen from right to left it sounds as though the car starts before the right side of the screen and continues on past the left side. The way movie tracks are created the surround system will take care of the front channel separation to a point.


You will not regret putting all the speakers behind the screen, in fact to keep the sound imaging the same across all 3 speakers they must be installed with the same material in front of them or else you will have to EQ one or the others.


Paul

 

I agree with having the same material between the speaker and the listening position, but screen size is limited to type of projector you're using and the amount of light you want to put on the screen. With both materials being acoustically transparent, just how much gain/loss would the screen fabric vs lets say GOM acoutisally transparent fabric put into the equation?

 

Quote:

Originally Posted by sbraab Movies mixed for digital surround are not using the front speakers to create a stereo image. Rather sound is routed to each discrete channel in a much more flat way.

Digital sound and discrete multi-channel didn't spell the end for stereo imaging in the front soundstage. There is still plenty of phantom imaging in between the front three speakers. It is very rare, at least in my experience, for the front soundstage to sound like three pools of mono rather than seamless and continuous image.
Quote:

Put on a nice symphonic sound track and shut off all your speakers except the R&L. Now sit in the sweet spot. You should notice that you don't have a very good sound stage, more like sound on the right and sound on the left.

Wow, what kind of soundtracks are you listening to? I tried your experiment with a couple of movie soundtracks that have an alternate 5.1-channel music-only track ('Superman: The Movie' and 'Yellow Submarine') and I heard plenty of central imaging when listening to the front L/R channels only. I even tried a film that doesn't have a separate 5.1 music track ('Immortal Beloved'), and could still hear imaging in the middle of the front soundstage when listening to the front L/R channels.


Best,

Sanjay

 

Quote:

Originally Posted by Paul Klassen You will not regret putting all the speakers behind the screen, in fact to keep the sound imaging the same across all 3 speakers they must be installed with the same material in front of them or else you will have to EQ one or the others. Paul

Hi Paul,


Certain perforated screens will attenuate the mid and high frequencies, which means the screen is not truly transparent like GoM. Therefore, equalization would be needed to restore the flat frequency response of the center channel. If the mains are placed behind acoustically transparent fabric they would not require equalization any more than speakers require equalization if their grills are left on. If the mains are also placed behind such a screen they would also require equalization.


I understand that newer fabric type screen designs are truly acoustically transparent and therefore do not require equalization. Likewise the proper GoM fabric is acoustically transparent and speakers placed behind it do not require equalization.


Larry

 

Quote:

Originally Posted by LarryChanin Hi Paul, Certain perforated screens will attenuate the mid and high frequencies, which means the screen is not truly transparent like GoM. Therefore, equalization would be needed to restore the flat frequency response of the center channel. If the mains are placed behind acoustically transparent fabric they would not require equalization any more than speakers require equalization if their grills are left on. If the mains are also placed behind such a screen they would also require equalization. I understand that newer fabric type screen designs are truly acoustically transparent and therefore do not require equalization. Likewise the proper GoM fabric is acoustically transparent and speakers placed behind it do not require equalization. Larry

Larry, what I meant to say is that if you have all the speakers behind the screen they will all be affected the same thus no equalization would be needed to match the speakers. You will, depending on the quality of the screen, need to match them to the surrounds. The Audyssey EQ in my Denon 4806 does a great job of that


Paul

 

Quote:

Originally Posted by sdurani Digital sound and discrete multi-channel didn't spell the end for stereo imaging in the front soundstage. There is still plenty of phantom imaging in between the front three speakers. It is very rare, at least in my experience, for the front soundstage to sound like three pools of mono rather than seamless and continuous image.

Sure there is some imaging going on, but anchoring specific pieces of the soundtrack no longer depends on the listener sitting on the point of an equilateral triangle.

Quote:

Originally Posted by sdurani Wow, what kind of soundtracks are you listening to? I tried your experiment with a couple of movie soundtracks that have an alternate 5.1-channel music-only track ('Superman: The Movie' and 'Yellow Submarine') and I heard plenty of central imaging when listening to the front L/R channels only. I even tried a film that doesn't have a separate 5.1 music track ('Immortal Beloved'), and could still hear imaging in the middle of the front soundstage when listening to the front L/R channels.

I have been itching to run something through the wires hanging out of the wall in my theater for a wile now so I put together a make shift test setup tonight. This consisted of my Proceed AVP, a cheap dvd player, an ADA PTM 650 amp (the proceed AMP5 is just too heavy to move) and 3 Boston CR6s across the front. The speakers were placed very tight at 4 feet from the side and 6 feet between.


The only thing I had from the above list was immortal beloved and it was defaulting to 2 channel audio. Without a screen I was unable to switch sound tracks. Way back when I used to use Crimson Tide as a reference so I pulled that out. Chapter 6 clearly has a huge hole in the middle of the sound stage when I unplug the center speaker.


Modern soundtracks like LOTR etc seem to have more imaging than older ones like crimson tide (The software is getting better), but I am still having a very hard time localizing anything in the middle with the center unplugged.


If I walk around the room, even standing 2 feet from the side wall in the back I can localize key parts of the sound track better than off axis stereo. Is it possible that when you turn off your center that your processor is kicking into a phantom mode? does dialog disappear?


--stefan

 

Quote:

Originally Posted by Paul Klassen Larry, what I meant to say is that if you have all the speakers behind the screen they will all be affected the same thus no equalization would be needed to match the speakers. You will, depending on the quality of the screen, need to match them to the surrounds. The Audyssey EQ in my Denon 4806 does a great job of that Paul

Hi Paul,


I understood what you were saying, I just don't agree with your premise that equalization is intended to match speakers.


According to Dennis Erskine, a professional home theater designer who is active on these forums, you can't use equalization to timbre match speakers, mains or surrounds.


He comments on the subject in this thread:

Four Side Channels?


However, if the screen isn't fully transparent you will still have to equalize any speaker placed behind it to restore it's flat frequency response, not to match timbre.


Larry

 

stefan,
Quote:

Sure there is some imaging going on, but anchoring specific pieces of the soundtrack no longer depends on the listener sitting on the point of an equilateral triangle.

Central imaging doesn't drift because of the centre channel speaker. It always anchors central imaging to the middle of the front soundstage, no matter where you're sitting. That's what it's there for.


But that's very different from your sweeping generalization of how movies are mixed for "digital surround". Even with three speakers, there is still stereo imaging going on in the front soundstage. Except instead of one phantom area you now have multiple: the left & centre speakers are a stereo pair, the centre & right speakers are a stereo pair, the left & right still remain a stereo pair.
Quote:

Modern soundtracks like LOTR etc seem to have more imaging than older ones like crimson tide (The software is getting better), but I am still having a very hard time localizing anything in the middle with the center unplugged.

I have an old DTS laserdisc of 'Crimson Tide' lying around somewhere, so I'll dig it up and try your experiment when I get a chance. It is still rare in my experience to find a soundtrack where the front three channels are basically mono pools with no phantom imaging between speakers. Almost every soundtrack I've heard has stereo imaging inside and outside the front three speakers.
Quote:

Is it possible that when you turn off your center that your processor is kicking into a phantom mode? does dialog disappear?

I use seven monoblock amps, so turning off the centre speaker simply means turning off one amp. The processor isn't even aware of it, so no change in decoding/processing. And yes, the dialogue does indeed disappear. But there are other bits of music and sound that image between the front left & right speakers; not always in the middle, but somewhere in between.


Best,

Sanjay

 

Sanjay,


I will agree my choice of the word flat was poor in the original post, I am not talking 3 totally isolated channels. However, comparing 2 channel to digital surround there is no comparison outside the sweet spot. My family room tv is a 2 channel only system if I sit outside the sweet spot there is no big sound stage, no precise imaging. Sure it doesn't sound like to unrelated streams of audio, but I can't close my eyes and imagine where every instrument is positioned like I can in the sweet spot. With digital surround, there is a more definite anchoring so even when I am out side the line of the speakers I can clearly localize things in the mix. The trade off is that the front sound stage is rarely as good as a good 2 channel recording. The advantage is that the 99% of the world who don't care about speaker placement still get pretty good imaging out of their system. (and this sells DVDs)


Let me twist the original question a little bit. Do you think it is possible to get good sound with solid imaging at every seat in the house? You can't have more that one or two seats at the point of the triangle and in most theaters the outside listener is closer to the corner of a square. Clearly a position where you don't get a good image from a 2 channel system.

 

Stefan,
Quote:

comparing 2 channel to digital surround there is no comparison outside the sweet spot

You may be using "digital" differently than I'm used to because I don't understand what it has to do with number of channels or surround sound. Whether I listen to mono or 6.1-channel soundtracks it's always digital, irrespective of number of channels. As for surround, it can be analogue or digital, delivered on 2-channel or multi-channel media.
Quote:

Do you think it is possible to get good sound with solid imaging at every seat in the house?

Sure, but you need more than 2 speakers. The more speakers you have, the less you rely on phantom imaging. The less you rely on phantom imaging, the more stable your soundstage (especially for listeners outside the sweet spot). But even with a 7.1-speaker set-up, where people spread throughout the room get solid imaging, you will still have a sweet spot that sounds better than other locations. It's unavoidable.


For the record, I haven't listened to music using only 2 speakers for something like 14 years. I always use a centre speaker. Same with the surrounds: I use two pairs because you can't get stable imaging at your sides and behind you with only one pair of surrounds (they can't be in two places at once).


So I do understand the limitations of 2-speaker playback that you've been talking about. The only reason I posted was because of your initial comments. Motion picture recording engineers have been fairly consistent about how they've been mixing sound over the years. Even before we got DD and DTS on home video, they were still mixing for 3 front channels (which were matrixed to 2 channels for delivery). So that didn't really change when technology went front analogue to digital or from 2-channel to discrete multi-channel. The main change was going from a mono surround channel (during the Dolby Surround era) to 2 and 3 surround channels (DD and DTS era).


Best,

Sanjay

 

Sanjay,


Great discussion, it reminds me that I really need to choose my words more carefully. When I say "Digital Surround" I should have said discrete multi-channel.


Just two last comments from me.


1. I was just in a neighbors media room where the L/R speakers were mounted in the front corners and there definitely is a sweet spot to that room. I think that had the speakers been pulled in closer that the rest of the seats would have much better audio imaging. Once I get some acoustic treatment in my room I will bring the B&Ws in and move them around to see what I can hear. Maybe I am just trying to justify my very tight placement. I will report back.


2. Where are the pictures of your theater. It sounds like you have invested enough effort into it to make it photo worthy.

 

Larry- and others

Quote:

Hi Luke, Marc meant positioning each main speaker so that the distance from the bass driver to the floor, ceiling, side walls and front wall are all different. When you place an In-Wall speaker in a wall you eliminate one dimension in which SBIR is a problem. That leaves the other two dimensions. If you end up locating the bass driver 1'6" from the wall, don't locate it 1'6" from the floor.

OK thanks, I had to go back and read again, it took a few minutes to absorb



Quote:

Going to the added expense of buying a perforated screen may not give you your money's worth if you're only concealing the center channel. If your projector and ceiling height permit it, you may want to consider increasing the size of your screen to get more WOW factor. On the other hand, regardless of the size of the screen, having an acoustically transparent, perforated screen would have some acoustic benefits versus an acoustically reflective non-perforated screen. If you went with a larger perforated screen, depending on the size you might end up placing your main speakers in the real front wall. Then the issue of angling the "false front wall" would be moot. Larry

One of the reasons I want to go with a acoustically transparent screen is that I seem to be overly sensitive to dialog that is coming from above or below the screen. Don't know why, it just distracts me. I even notice it in well executed systems. I also seem prone to distraction by setups that don't have all 3 fronts at the same height. During R-L/L-R pans I notice it and it pulls me out of that suspension of disbelief. I think with an acoustically transparent screen I can assure that I wont be distracted by dialog coming from off screen by having the center placed behind it. This would also allow me to place all 3 fronts at the same height regardless if the R/L end up inside or outside. So, I think I still would justify the added cost even if I have to place the R/L outside for a better angle. PS not sure I follow you on your last sentence.


stefan-

Quote:

I feel that for movies the 45 to 60 degree recommendation is moot.

I may be taking you too literally, but doesn't that recommendation come from THX?


Edit- I see Dolby recommends 22-30deg on their site, and I can no longer find the deg recommendation on the THX site.


Paul, William, Larry-

I follow the conversation on striving to have all 3 fronts behind the same material. The screen options I am pursuing are all weave fabrics not Perf. as I understand it they have much less of an impact than the perforated technology. But I do understand that it could be something I would have to deal with/correct, and will add that to the other factors trying to make the decision.


I may be making too big an issue out of the decision, maybe I should pick a direction and move on. It boils down to this; I am afraid that if the fronts are only 7-7.5 ft apart with me sitting 12-13' away, the sound stage won't seem large/wide enough. Also, would audio pans and effects that move off, or occur off screen to the R/L sound correct?


It seems to me that if I placed the R/L just outside the screen instead of behind it, I wouldn't risk those problems. But I didn't know how bad it would be to have the R/L close to the side walls.


No response on the thought of a slight angle/toe in of the outer part on the front wall to deal with the side wall problem if I mounted outside the screen, so I take it that idea is a non starter.