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Dealing with a large TV between speakers

Thought I'd post this since it's a glaring problem (somewhat literally, very figuratively). I've got a 50" rear projection LCD TV between my speakers that has to be there for many reasons (HT/living room/etc). Soundstaging on the x and y planes seems OK, perhaps a little narrow, but forget about the Z plane. All the action seems to take place horizontally between speakers, with vocals perhaps a bit projected forward.

I've done the Master Set method on my speakers. They are ~3ft from the rear wall and about 7.5' apart (measured from drivers) . The TV is about 20" out from the rear wall and 4.5' wide. There is roughly 18" between the speakers and the sides of the TV.

For a better visual, I've created a drawing here that I've used for submission to various acoustic panel websites.

As you can see, speakers and TV are along the long wall, and I only have about 12' total between that wall and the wall behind me. I can't move the speakers out too much more, and based on Master Set and the rule of thirds, they seem to be where they should and they do sound good there (no bass bloat, clear imaging, etc). There is roughly 2' of space between the rear wall and my head.

What I've done so far for treatment are the acoustic and diffusion panels you see in the picture, and I've wrapped thick round foam pipe insulation (the tubes you can buy at Home Depot) vertically along the sides of the TV, which seems to help. I've also experimented with hanging a diffusion panel or light foam panels over the front of the TV to cover the front. However, I'm not noticing much of a difference with the front of the TV treated or not, surprisingly (I assumed that there would be more glare and smearing with such a large, untreated, reflective surface between the speakers and directly in front of me).

Outside of throwing a blanket over the TV (which I tried, didn't really work) do you see any way to accomplish more depth to the soundstage? Questions and comments welcome, but keep in mind, I can't move the TV.
tholt
bryoncunningham
893 posts
 
I agree with Shadorne that the principal problem lies in your system's orientation along the long wall. I assumed, looking and your photos and overhead plan, that moving the system to the short wall was not an option. If that is an option, then that will be your best solution by far.

However, if you must keep your system on the long wall, then I respectfully disagree with Shadorne that your television is not a factor in your efforts to get the best sound possible with that configuration. I too have a large TV screen between my speakers. When I sit down to listen, I place a large piece of acoustic foam (12" in depth) in front of the TV screen. This minimizes undesirable comb filtering effects by reducing first order reflections from the TV. The result, IME, is an audible improvement in image focus and soundstage depth.
learsfool
1,215 posts
 
Looking at your drawing, I would definitely agree with Shadorne that the TV is not the main issue. In fact, I would say that the sliding glass door behind the left speaker, and the entryway behind the right speaker probably have even more to do with the loss in your soundstage depth than the TV in-between the speakers does. But the main thing is that they should ideally be on one of the short walls.

My brother has a similar situation to yours, and also has a large TV between his speakers. He experimented with removing the TV (and also covering it as you did) and found it made no significant difference to the overall soundstage, so he put it back. He unfortunately cannot place his speakers on the short wall. If you can, this is by far the best solution. If not, I would also consider curtaining the screen door somehow, and if there is not a door on that entryway, considering putting something there as well.

I myself have a large plasma TV between my speakers (as well as my audio rack, for that matter), but they are on a short wall and the speakers are also horns, so their shape minimizes the effects of the room anyway by directing the sound much more where I want it to go, even though the set-up is very far from a theoretical ideal. I also have plenty of diffusion throughout the room, which is also much larger, so I have plenty of space behind the listening spot. The effect of the TV is therefore very minor in my set-up. I have a huge soundstage however you want to measure it - width, depth or height. I am sure it could be improved by better placement, but that is not possible with the other furniture in the room. I hope someday to have a dedicated room, but that is years off yet.
tholt OP
551 posts
 
Appreciate the responses thus far. Unfortunately due to room layout, it's totally unpractical for me to place speakers against either of the short walls. I would love to try it someday, but would have to put them back anyway, so maybe better left untried for fear of it actually sounding better.

Tonight I tried moving the speakers into the room as far as practical and fine tuning them in that position, ended up being 6 more inches further from the rear wall. The 3D has improved slightly, but not significantly. I think Bryoncunningham is right -- for me it's going to be a matter of inches. And yes, she has said that.

@Nikturner920 - yes diffusion panels are DIY. The diffusion squares come 12 to a box, very cheap, and fit together like puzzle pieces. Though more professional and costly diffusion panels likely have better results.

I may try removing the TV to see if the soundstage improves. If so, I know that a mounted flatscreen TV could be a viable solution.
tholt OP
551 posts
 
@ Learsfool - there are curtains over the glass door and window. Not very thick, but there nonetheless.
peter_s
1,348 posts
 
Tholt - take your TV out temporarily and see if it is indeed the problem. Thus we can stop speculation on that!

Are you sure the absorbers are good behind your speakers? In my room, I preferred diffusors, but I was using Quads then. I would say, never assume that treatments are for the best - play with them some.

That said - I like your diffusors too. I build my own Skyline diffusors out of balsa wood. Can you share more about them, parts, construction, etc?

Thanks, Peter

PS - I have friends with a similar layout to yours. They are using GMA Europas and getting very good soundstage along the long wall with heads near the rear wall on a sofa. It must be possible.
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