SQ Issue My New TV Has Caused - Now I Need Treatment Advice

[Bonzo]

So I've never needed room treatment before and I'm looking for a bit of advice.

My room is a big rectangle, probably about 15' x 24' x 8'. The bi-polar speakers are along the 15' wall, spaced about 8' apart, about 20" from the back wall, slightly toed in, and leaned back about 3/4".

My old TV was a big CRT box made from MDF that sat right between the speakers. This basically created a wall between the speakers which limited sound stage and spaciousness. Years ago when I first got my speakers I was a bit disappointed by this, but knew when I finally got a new TV this issue would change.

So here I am with a new 65" flat panel plasma and I have a ridiculous amount of change, and NOT for the better. What I have right now is a temporary set up until I have time after the holidays to finalize things. The 2" thick TV is set smack in the middle of our coffee table, centered between the speakers, about 15" from the back wall. The sound I have now is WAY WAY more spacious. Did I say WAY more? But it's WAY too much, to the point of almost being echoey. The sound is now unclear and imprecise. Imaging is lost. There is even a harshness that makes things hard to listen to. I was expecting / hoping to get a more spacious sound (which is what bi-polar speakers are for), but the current sound is totally tainted. Right now, I HATE my sound.

I believe what's causing the huge issue is the "tunnel" behind the TV, but I'm not 100% sure. If I sort of lean over the TV and talk I can hear a slight weird sounding echo of my voice. When I do the "clap test" I get slight reverb.

My original plan was to hang the TV on the wall, but now I'm second guessing that, because one way or another I think I may now need some room treatments. The questions are, where, and what kind (absorbing or deflective)?

If I hang the TV on the wall, then I will loose most of the 15" tunnel in back, but not all. I believe with the bracket it will be about 2"-3" off the wall. With this amount of space, I still have a tunnel back there, but none that I could put sound deadening on in fear of not leaving "cooling" room for the TV. So my only option would be treatment behind the speakers themselves, which I'm not sure is the best thing to do for bi-polar speakers.

If I put the TV on a stand, this allows me to move the TV in and out from the wall to adjust the sound. It will also allow me to put treatment behind the TV, either on the wall, or maybe even on the back of the TV itself (in minimum amounts, like little blocks in various locations.

Right now it's hard to move the TV closer to the wall to see how that effects things. I'm thinking I might try putting some pillows back there just to see what happens. I can do some experimenting for sure.

But I'm typing this post in hope that there are other more trained and/or experienced folks out there who have encountered this situation before, and know where/how I should proceed.

Thanks in advance for any advice and assistance you can offer.

Cheers ---- Bonzo

[Bonzo]

Sorry guys, I am using my MAC at home and hit some combination of buttons that sent my post before I was done. In other words, some of you read a 1/2 finished post. If you will, please reread my post to get the entire thing and the questions I have. The new finished post has my signature at the bottom.

Thanks for your help.

Bonzo

[repeetavx]

Let us know how the pillows work. That would be my first guess.

My favorite place to buy acoustic Panels, Acoustimac.

There are lots of other good ones.

A primer on room acoustics and treatments.

An Acoustimac competitor Realtraps.

Gearslutz room treatment resources.

[Gary Cook]

What's the location (out into the room) of the panel compared to the L/C/R?
If the panel is in line with or in front of the L/C/R then that's a big problem. Since you can't, at the present time, move the panel back then maybe try moving the speakers forward.

Happy New Year
Gary

[paintedklown]

Just taking a stab at this for you, and if my thoughts are "off the wall" then someone please correct my line of thinking.


With your speakers, I would put a diffuser panel behind each speaker, with the middle of the panels at tweeter height.

If you plan to keep the tv on the stand (vs wall mount), I would suggest putting an absorption panel behind the tv as well. If you wall mount it, I don't think you would need much more as far as panels on the front wall. Once again, someone please correct me if I am wrong.

Now for treating the rest of the room, I would advise to use normal treatment methods to keep the room tamed as best you can. IMO, that would be 1 absorption panel at each first reflection point (one on the left, one on the right) of the tweeters, and 2 panels on the back wall (behind where you sit). Once again, place them with the center at tweeter height (all of the panels would be mounted at the same height, and mounted vertically) where your speakers are aimed at on your back wall.

Lastly, treat the corners with Bass traps.

In total, that is 2 diffuser panels, 4 absorption panels, and 4 bass traps. All in all, it shouldn't be too expensive to do these things, outside the bass traps...those can get VERY costly IMO.

I think if you did these things alone, you will find yourself enjoying your system again. Of course, these recommendations are essentially the same ones used for direct radiating speakers, so I could be 100% wrong on this. I am not talking from experience, but merely from my understanding of room treatments based on what I have read/saw/heard. Take my advice with a couple grains of salt, and good luck!

EDIT: was just thinking two channel only. This may be different, or require additional panels on the front wall for an HT/multi ch setup.

[yves]

Optimizing speaker placement and listening position is always the best way to start. 20" is way too close to the back wall. For dipole speakers in a rectangular room you can try the following speaker placement and see if it makes a difference to the sound. The distance from the center of the woofer face to the wall behind the speaker is the ceiling height times .618, i.e., 8' x .618 = 4.944'. The distance from the center of the woofer face to the side walls is the room width times .276, i.e., 15' x .276 = 4.14'. So the distance from the center of one woofer face to the center of the other woofer face is 15' - 2 x 4.14' = 6.72'. The listening position and each speaker position should form an equilateral triangle, so the distance from the wall behind the speaker to the listening position is 6.72' x .866 + 4.944' = 10.764', which is in fact not very far from where you would be sitting now if you were already following the equilateral triangle rule.

www.cardas.com/room_setup_rectangular_room.php

[Bonzo]

Dec 28, 2013 14:22:45 GMT -5 repeetavx said:

Let us know how the pillows work. That would be my first guess.

My favorite place to buy acoustic Panels, Acoustimac.

There are lots of other good ones.

A primer on room acoustics and treatments.

An Acoustimac competitor Realtraps.

Gearslutz room treatment resources.

Thank you very much repeetavx for all the links. This will be very helpful.

[Bonzo]

Dec 28, 2013 14:46:03 GMT -5 Gary Cook said:

What's the location (out into the room) of the panel compared to the L/C/R?
If the panel is in line with or in front of the L/C/R then that's a big problem. Since you can't, at the present time, move the panel back then maybe try moving the speakers forward.

Happy New Year
Gary

Right now the panel is behind the front of the speakers. I'm guessing it's about half way between the front of the speakers and the wall.

Funny that you say being even with is a big problem because up until the new TV that's exactly what i used to have. With that big CRT box in the middle, it was impossible to move the speakers out enough to get much in front of it. By impossible I mean "not possible and still be room friendly." [Remember I have a wife.... ]

[Bonzo]

Dec 28, 2013 14:51:03 GMT -5 paintedklown said:

Just taking a stab at this for you, and if my thoughts are "off the wall" then someone please correct my line of thinking.


With your speakers, I would put a diffuser panel behind each speaker, with the middle of the panels at tweeter height.

If you plan to keep the tv on the stand (vs wall mount), I would suggest putting an absorption panel behind the tv as well. If you wall mount it, I don't think you would need much more as far as panels on the front wall. Once again, someone please correct me if I am wrong.

Now for treating the rest of the room, I would advise to use normal treatment methods to keep the room tamed as best you can. IMO, that would be 1 absorption panel at each first reflection point (one on the left, one on the right) of the tweeters, and 2 panels on the back wall (behind where you sit). Once again, place them with the center at tweeter height (all of the panels would be mounted at the same height, and mounted vertically) where your speakers are aimed at on your back wall.

Lastly, treat the corners with Bass traps.

In total, that is 2 diffuser panels, 4 absorption panels, and 4 bass traps. All in all, it shouldn't be too expensive to do these things, outside the bass traps...those can get VERY costly IMO.

I think if you did these things alone, you will find yourself enjoying your system again. Of course, these recommendations are essentially the same ones used for direct radiating speakers, so I could be 100% wrong on this. I am not talking from experience, but merely from my understanding of room treatments based on what I have read/saw/heard. Take my advice with a couple grains of salt, and good luck!

EDIT: was just thinking two channel only. This may be different, or require additional panels on the front wall for an HT/multi ch setup.

Thanks for the detailed and time taking post.

RED = This is my preliminary plan of attack. We'll see where it goes.

BLUE = This will be my second plan if the red plan above doesn't do the trick.

Regarding the rest of the room, you see, until now, I've never needed any of this. Between the wall to wall carpet, big cloth couch, cloth lay-z-boy, cloth lamp shade, CD case wall, blinds, and 2 open doors, the sound has been really natural without any treatments. If I did anything I'd add some bass traps since my one back corner has excess bass, but I'm not sure where to put it. (There isn't much room) I think I'd have to make them home made at custom sizes. From what I've read just using some large fiber tubes filled with sand works well.

[Bonzo]

Dec 28, 2013 19:38:02 GMT -5 yves said:

Optimizing speaker placement and listening position is always the best way to start. 20" is way too close to the back wall. For dipole speakers in a rectangular room you can try the following speaker placement and see if it makes a difference to the sound. The distance from the center of the woofer face to the wall behind the speaker is the ceiling height times .618, i.e., 8' x .618 = 4.944'. The distance from the center of the woofer face to the side walls is the room width times .276, i.e., 15' x .276 = 4.14'. So the distance from the center of one woofer face to the center of the other woofer face is 15' - 2 x 4.14' = 6.72'. The listening position and each speaker position should form an equilateral triangle, so the distance from the wall behind the speaker to the listening position is 6.72' x .866 + 4.944' = 10.764', which is in fact not very far from where you would be sitting now if you were already following the equilateral triangle rule.

www.cardas.com/room_setup_rectangular_room.php

Thank you for the detailed post. This is a cool link for checking things out. However, as detailed as this all is, there is no way this mortal man will ever achieve such a listening room. What is proposed by all this is for just that, a listening room, an ultimate listening only room. Not a family friendly multi-purpose music / TV /theater room. There is no way I can have my speakers 5 feet out into the room. I even jokingly said to my wife that it's the best placement and she gave me one of those "are you fracking kidding me" stares. She then started talking about having to move out. I'm not ready for all that so it's a big no way.

Once I get the TV stand and TV placement thing all worked out, I am going to re-evaluate my speaker placement with some listening tests. But I'd say at most I might be able to move them out maybe 2 or 3 inches more than they are but that's it.

[paintedklown]

No problem. Good luck, and please let us know how everything turns out.

[Bonzo]

So far......

So, all, for my first attempt at seeing what was going on, what I did was "jerry-rig" a wall hanging dowel thingy. I took some 3M Command hooks and zip tied them to a 4 ft long 3/4" dia dowel. I then used some 3" L-brackets to hold the dowel up and away from the wall. I then hung 2 fluffy cotton towels from the rod, folded so they are about 12" wide each, hanging down about 30" or so. Basically, imagine a wide bathroom towel rack on the wall behind my TV.

Unfortunately I have not gotten a chance to do any music listening since installing my towel rack. What I have gotten to do is watch a bunch of TV, and I can tell from just that, that the sound is much better defined again. Before the towels even TV voices were hard to make out, and it all just sounded like one big blob. I now have back some distinct left / right separation and imaging. So I think I'm on the right track......

Next up will be some serious music listening (hopefully this weekend). I also plan trying to move the TV back a bit to see what that does.

More to follow.......

[The Mad Norseman]

1) Don't wall mount your HDTV, (that puts it too far away and creates 'a tunnel' between your front speakers that also would look odd).
2) Get some acoustic panel treatments on the walls in the space behind your front speakers & TV, and also to the front/sides of your room forward of your FL & FR speakers - catch those first reflections especially. Lastly, lay in a pair of bass traps for the front corners (and maybe the rear corners as well).
3) Sit back and enjoy your improved sound.

[yves]

I forgot to mention, those "rules" are just a theoretical place to start experimenting. Move your speakers to where they sound best, and then carefully move them back again before your wife comes home so that she never has to find out that you moved them.

P.S. - If you have enough available space to store some acoustic panel absorbers and bass traps in another room, perhaps you can temporarily move them to this other room so that they will be hidden from view each time when you won't be using them. It's relatively easy to DIY them in such way that they can be portable.