re: Why do people mount their TVs so high?

This is the answer in new builds where above fireplace is the only option. Though ours doesn’t have a remote and now I want to upgrade.

If you sit on the couch in a natural position with your neck straight, your gaze is a good 6 feet up.

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I know he said “imaging” specifically but I think it’s probably more accurate to say that most decent stand-mounts simply sound like garbage when placed against a wall. It does frick with imaging but it’s more about the overall tonality of the speaker and the fricked up lows/low mids when rear-ported speakers are placed right up against the wall. And no amount of “room correction” EQ can fix it.

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You are now talking about SBIR (speaker boundary interference) which is a type of boundary induced comb filtering. This will start about 500hz and under because this is where sound waves start to radiate like a sphere instead like a ray so below 500hz and down to about 125hz when the wave becomes purely spherical the effect will increase. The good thing about HT is usually the last 2 to 3 octaves are being crossed to a sub so the worst offending frequencies are not present in full volume how quickly amplitude is reduced by frequency depends on the slope of the crossover normally either 12 or 24 dB per octave. This becomes a really complex issue because you have acoustic space loading increasing the amplitude of the low frequencies and SBIR both producing constructive and destructive interference which produces wild swings in the frequency response. So just like room modes you can not EQ them out. So what is the solution because almost no one with even 5.1 much less something like 15.1 is going to have all those bed and height channels sitting feet away from the wall. The solution is pretty simple you put absorption material of the proper thickness to handle the lowest offending frequencies on the boundaries that are causing the SBIR issues. Easy peasy but it is one reason why it is very rare to have really good sound in a non-dedicated theater room since most people are stuck with spousal acceptance factors that prevent seemingly randomly placed pieces of foam on the walls. Even if you build or buy pretty absorption panels they will almost always be in places that look odd for "art". Especially when you have 9 or more speakers fixing SBIR issues and damping the first reflections of each speaker ends up covering a lot of wall. Then you also have to add detraction panels and the walls start looking like some weird modern art.

The speaker's interaction with the room is an incredibly complex and important part of a good listening room or HT. The vast majority of HTs give little thought to this interaction but when someone wants to delve into it I recommend these two books:



Once you have read and digested the 1000+ pages in them you will have a basic technical grasp of small room acoustics and how speakers interact with a room. Most of the things you learn are depressing because each new concept you learn shows you just how difficult getting a nice flat response in room is. You also learn how important good sound power and directivity index are if you want a speaker that reacts well to room correction, then you learn how rare that actually is in most commercial speakers.

I didn't mention but front ported or sealed speakers are easier to get to play well with rear boundaries.

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I disagree with this. Imaging from your FX speakers (heights, rears) isn’t that important because of how Atmos works but the vast majority of audio content is still mixed exclusively in the LCR channels. So the stereo image from your L/R mains does still matter quite a bit for dialog.

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I disagree. If you are using a phantom center channel mix then the LR imaging needs to be fairly holographic to produce a stable center channel. If you are using a L/C/R mix then imaging is a really low priority (and I am an imaging nut in 2 channel) because the spacial cues are done with by varying the amplitude between the L/C/R. The biggest issue with you run into with L/C/Rs is people using horizontal MTM speakers for the center because they usually fit better than a center identical to the left and right channel speakers. horizontal MTM speakers have issue with lobing and comb filtering which really screws up the balance of the frequency response in the horizontal plane. This is less of an issue in the vertical plane and the reason some vertical MTMs can actually be rather good.

One of the big differences between most two-channel rigs and most HT rigs is most two-channel rigs are designed and tuned around a single listening position so if you end up with a room mode right on your listening position you can move the listening position forward or back about a foot or so and avoid that mode. There are going to be destructive and constructive modes all around the room below the Schroeder frequency of the particular room so you have to balance everything by fixing the worst ones which may force you to live with another not so bad one. This single listening position is also why imaging is so important with 2 channel. With HT even if you lean toward a primary listening position or even row most HTs need to have reasonably balanced sound over a number of listening positions this takes much more work and much more time running sweeps. The much larger sweet spot is why HT depends on multiple speakers instead of depending on the imaging because even with speakers that have laser-sharp imaging it is only going to be present at one spot. One of the loopholes with HT systems is that they crossover the lower frequencies so a lot of the spectrum under the Schroeder frequency goes to sub(s) and you can smooth the bass response over a wide area by using multiple subwoofers. Reference the white paper done for Harman by Todd Welti who was a protege of Toole. White paper PDF

I'll shut up now as I am already far beyond the scope of an OT thread.

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The AV "rule" is 1/3rd of the way up the screen should be ~48" off the floor.

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Mine is only about 4' off the floor. And I have a wood stove (no fireplace) in the den where we watch TV in my trashy country house.

or just have a big enough room thats easy to see?

we have the frame TV above ours, we like to look proper with a family portrait or painting up when company comes

cant be looking low class with normal tv above the fireplace...just trashy

you mother frickers worry and bitch about how other people spend their money, how they dress, how they decorate their home, what sports kids play


yall frickers just bitch to bitch about other people. as bad as gossiping women, I swear.

this board has just turned into a gossip session.

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Once you have read and digested the 1000+ pages in them you will have a basic technical grasp of small room acoustics and how speakers interact with a room.

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Did you just tell me to read a book?

I know what SBIR is. My home studio has GIK panels at first reflection positions (including behind my nearfields) as well as corner traps and a 4” membrane panel behind the MLP. Acoustic treatment still won’t make rear-ported speakers sound good against a wall unless you plug the ports. For starters, the vast majority of panels are designed to deal with flutter echo, not low frequencies, so your sound still gets either boxy or thin even with panels behind them. Second, there’s the fact that the boundary interferes with the way the ports themselves work.

The best way to get deal with rear SBIR from HT speakers is either to A) get them away from the wall or B) use sealed / front ported speakers. (Actually the best way is to soffit mount them but that’s a whole different level of investment.) But most good bookshelf speakers are rear ported. Once you have rear ported bookshelf speakers away from the wall, treatment can help further. But the first step is to get them out into the room.

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If you are using a L/C/R mix then imaging is a really low priority (and I am an imaging nut in 2 channel) because the spacial cues are done with by varying the amplitude between the L/C/R.

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I mean, that’s the same way imaging is maintained in 2-channel. There are other tricks like Haas delay but 99% of the work is simply done by managing the volume in the two channels. The difference is just that a center channel makes it easier since you don’t have to maintain a phantom center. Imaging issues are less obvious to the listener, but they still exist.

But my larger point was that the way the LCR channels work is fundamentally different than how FX channels work, at least using Atmos. The FX content is actually encoded in “3D” and thus has a physical position encoded with each sound. So your surrounds and heights can theoretically be placed wherever the hell you want as long as your receiver knows their position. AFAIK that is not the case for content in the LCR channels, even in Atmos. Maybe I misunderstood and that’s not what you were talking about.

Since those channels are mixed “traditionally,” the placement of those speakers and the ability of the viewer to localize those sounds matters more, relative to FX channels. I quite often see cheap 5.1 systems where the L/R speakers are on wall-mounts, 6” from the ceiling, placed 15-20’ apart from each other. Or worse, I see 5.1 systems with decent bookshelf speakers that are literally placed on top of bookshelves or on wall mounts, again way too high and way too far apart. Meanwhile the center channel is sitting on top of a media cabinet or something, 5+’ lower than the L/R channels. It’s a recipe for a bad soundstage across your 3 most important channels.

Most people who can’t use floor stands would be better-served by actual on-wall speakers mounted lower on either side of the TV, assuming their TV isn’t also against the ceiling.

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One of the big differences between most two-channel rigs and most HT rigs is most two-channel rigs are designed and tuned around a single listening position so if you end up with a room mode right on your listening position you can move the listening position forward or back about a foot or so and avoid that mode.

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Agreed, dealing with the room is much more difficult for a true HT setup. I also think it’s largely overrated. The rear boundary/port issue, if it exists, will usually be an issue at all listening positions. While it is technically a “room” affect, it’s much easier to resolve than modes or other reflections. The primary job of LCR channels in 5.1+ is to reproduce dialog. The problem is that the frequencies most affected by cramming bookshelf speakers against a wall are also the most important frequencies for dialog intelligibility. If you can fix that, the overall sound will be much better. Sub placement is probably the next biggest issue. And then you can decide whether further treatment/tinkering is worthwhile. The point being that many (most?) untreated rooms can still sound a lot better without necessarily resorting to putting up panels and bass traps everywhere.

Pretty much.

My house is an older house but the two choices of where to put a TV were over the fireplace or on the back wall against the kitchen.

The problem in my case was more that there are built in cabinets on one wall and, while it was designed to hold a TV, it was shaped with an old style CRT in mind and not a HD flatscreen.

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Do they do it because it looks good over the fireplace?

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Not my style either. My tv is mounted above a sonos sound bar which is mounted about 42 inches from the floor. A nice entertainment cabinet is below. The fireplace has a framed picture over it.

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Do they do it because it looks good over the fireplace? There is no way it's comfortable watching a TV 8 to 10 feet in the air.

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They do it because they don't have to wriggle the rabbit ears or change the channel with a pair of vise grips....when you ain't a poor you have options that the poor can only dream of....