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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
tholt OP
551 posts
 
Hi Buconero - center channel is for movies only. Music is strictly 2 channel.
nikturner920
144 posts
 
I get great soundstaging with my speakers on the long wall and my listing position near the rear wall. Almost as good as shortwall placement in my room but with much better bass response. My room is well treated though.

I think the comments about removing the TV are good. You need to figure out what each piece of room set up contributes to the sound. It is possible that with the TV completely removed doesn't make that much of a difference.

Do you have the speaker cable length to try the speakers way out into the room? Just to see if you can get any depth. There are some set up that just don't do depth well.

It takes a long time and effort to get a handle on room acoustics.

Seriously, you should write up some plans for those diffusors I would love to build a set. Really non recording studio look.
rrog
1,958 posts
 
If this is about a two channel system I'm in. I don't do HT.

Tpreaves is correct regarding the entry behind the right speaker. This can act like a mini echo chamber and really mess with your sound. Clap your hands while standing in the entry and listen for unwanted echo. If echo exists you may want to treat the entry to eliminate the echo.

From your drawing you are set up correctly and I prefer the long wall, but you may want to either spread the speakers farther apart, pull the speakers farther into the room or a little of both.

If you want to know how the TV is affecting the sound you can temporarily remove it.

When making adjustments or treating your entry, be sure to do only one thing at a time. Don't do anything else until you realize how a single change affected the sound.

One thing I don't hear mentioned is the leather couch. Your leather couch is a large reflective surface right in the listening position. It is my experience that leather couches are not good for the sound. Try covering your couch with a blanket and see if you hear the difference. Leather couches affect the sound in a similar way to having a non-treated wall behind your head. I'm surprised nobody has mentioned this before.

I would be interested in knowing what products you are using on the wall behind the speakers and the wall behind the listening position. A good rule to follow is "live end dead end". In other words, if you are treating the wall behind the listening position don't treat the wall behind the speakers.

Only make one change at a time.
ngjockey
1,042 posts
 
Less toe-in. Maybe a bit closer together. Try swapping diffusion panels position with absorption panels. Maybe some corner foam or soffit traps at ceiling/wall on front and back walls.
kijanki's avatar
kijanki
4,428 posts
 
Tholt - I have exactly same situation, same TV and similar stand plus exactly same Hyperion speakers. Speakers are on the long wall and sofa is on opposite wall. I agree with Shadorne that reflections from the wall (especially back wall) and not TV create problem. I tried to cover TV with multiple blankets and it doesn't change imaging (pretty good). I bought high density 2" thick sound absorbing panels effective equally down to 100Hz and plan to finish them and hang (twelve 2'x 4'). I was once in the room with all walls made of such panels and effect is amazing. My own voice sound cleaner and other people voices come from exact points. I have also very tall cathedral ceiling (starting at 12') and too much reverberation. Windows curtains (or similar covers for the walls) don't help much because if I can hear sound standing behind them with almost no loss, then sound will bounce back from the window (or wall) thru the curtain.
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