How to Position Speakers for the Best Sound

I recently responded to a question from a reader on proper speaker placement, a complicated subject that can never be given enough attention. It involves not only how you or I might prefer to position the speakers, but also possible veto by the décor committee. The latter generally demands that the speakers be invisible. But no one has as yet quite solved that conundrum, apart perhaps with in-wall speakers. Few reviewers and commentators, who generally do their work at home, want to swiss-cheese their walls with a constantly changing parade of in-wall candidates, all requiring different configurations.

Absent that, the committee often demands that the speakers be as out of sight as possible. If they’re small, they’ll sometimes be shoved into the nearest cubbyhole or atop the deepest, highest shelf. If large, they must be pushed tight against the wall behind them.

I can’t offer advice on how to work around décor concerns, but for those with the persuasive skills to make an end run at the Better Homes and Gardens objections, perhaps I can help.

Put Small Speakers on Stands
Small speakers are usually called “bookshelf speakers,” but putting them on a bookshelf is only slightly better than that proverbial cubbyhole. Bookshelf speakers are best used on stands, well away from large objects and out from the wall behind them by a foot or more. If they’re ported, with the port in back, putting them hard against the wall will block the port. Even an inch or two of spacing might still alter the designed port tuning, compromising the speaker’s bass response.

The stand itself is also important. For most speakers its height should position the tweeter at or slightly above your seated ear level. While seated ear height typically varies between 36- and 38-inches, it can vary significantly, particularly with recent changes in furniture design. For example, powered seating can be higher than this to accommodate its motors and other moving parts. And the folding chairs typically used at audio shows (and at some dealers as well), lack the compressible padding of home furniture, often resulting in an ear height of over 40-inches — something to keep in mind at a show or dealer audition.

Some stands are solid, usually of wood. Others have hollow metal legs that can be filled and dampened with everything from birdshot to kitty litter (really!). But the correct height is more important than the construction.

Stability is important as well. A heavy bookshelf speaker atop a flimsy stand is an invitation no two-year old can resist. Even if the latter isn’t an issue, you should still secure the speaker to the stand. Stands dedicated to a specific speaker often have provision for this. If not, a few small blobs of Blu-Tac (or the equivalent) should do the trick. But this can make it a chore to later remove the speaker (hint, secure the stand by putting a foot on its base, then exert a firm but steady pull on the speaker, tilting it slightly to break the putty’s bond).

Pre-made stands can be pricey. Alternatives range from a stack of concrete blocks (this will definitely please the interior design committee), though be sure to protect the bottom of the speaker from scratches. A stack of large books can also work (décor acceptance will, of course, depend on the titles). Homemade stands are also possible. They don’t present much of a build challenge if you’re handy and have access to a table saw (home centers will also often cut wood to size).

Experimentation Is Key for Tower Speakers
Floor-standing or tower speakers follow the same rules, though of course no stand is needed. But do be conscious of the height, which can’t be altered as easily as with a stand-mount (note the shift here in calling bookshelves by a more appropriate name, stand-mount). If the tweeter in a tower speaker is above or below ear level (and it sometimes is) a canny designer can account for this, to a degree, in the crossover. But if not, a tweeter that’s too high can affect the performance for seated listeners. You might find that a slight tilt, either backwards or even forward, can help. Experiment, but don’t tilt the speakers so much that it compromises their stability.

Speaker placement in a broader context was also part of the question I received. Specifically, how close to the wall or walls should the speaker be positioned, and assuming the speaker has one or more ports (most do), should the port(s) be in the front or back?

As to the port location, this should make little difference. The wavelengths that a port deals with are far longer than the depth of any practical speaker cabinet. But a port can also generate unwanted resonances, and even produce a type of port noise called chuffing. Both of these problems are rare in my experience, but if they are a concern they will generally be less audible with a rear port. I had an odd experience with a front port on one occasion where during particularly vigorous bass passages I could actually feel a breeze coming from the port even though it was 10 feet away!

Apart from blocking the port as mentioned above, the optimum distance between the speaker (either stand-mount or tower) and the wall behind it will be entirely room dependent. As I’ve said in many reviews, I can tell you what a certain speaker’s bass sounds like in my room, but not (with any precision) in yours. That’s true of any review from any reviewer. This can hopefully be mitigated, in a given listening room, by properly positioning one or more subwoofers and/or using the EQ provided by automated room-correction systems such as Audyssey or Dirac Live.

Experimentation is the only solution for proper placement, from the setup of the main speakers to the use of subwoofers. While setup can be more restrictive in a home theater setup than for a simple two-channel system (since the locations of the speakers are constrained by a screen) the use of subwoofers and perhaps room EQ are not solutions many two-channel listeners are likely to consider.

One location you’ll want to avoid is placing a full-range speaker in a corner, unless the speaker is specifically designed for it. Also try to keep the speakers away from the sidewalls by a least a couple of feet. Experiment there as well, if possible.

To Spike or Not to Spike?
Then there’s the subject of spikes, those sharp little pointy things that come with many speakers (and stands). The argument is that by better securing the speaker to the floor, vibrations will be reduced thereby improving the sound. That’s debatable, though spikes can reduce wobble if properly installed. But if the speaker sits on a carpet, the spikes must penetrate it to reach the floor underneath. Not all spikes are sharp enough for this, so will be worthless on a heavy rug though perhaps helpful on a bare floor. The spikes won’t leave a visible mark on a reasonably thick carpet, nor result in irreparable damage to it, but you might want to avoid using them on that antique Persian rug! And if there are valued hardwood floors underneath the carpet or rug, you might want to avoid this tweak as spikes can leave puncture marks in the wood. Small metal shims are available for placement between the spikes and the floor, but these are only practical if the speaker will sit on the hardwood itself, with no carpet or rug in between.

I’m agnostic on the subject of spikes, but don’t currently use them as my speakers do sit on a rug with a hardwood floor beneath it. But in any event don’t add spikes until you’ve first settled on the final speaker positions. And if you tend to move your speakers out from the wall for serious listening, then back against the wall for aesthetic reasons, spikes are not a good idea.

Finally, I advise against aiming the left and right front speakers straight ahead (vs. angling them in toward the center seat). This sort of setup is often recommended for speakers with a bright response, and might produce a more balanced sound from the center seat. But listeners seated off-center might end up directly on the axis of one of the front speakers and far off axis from the other. Unless you’re the only listener, experiment with toeing in the speakers to determine how much of an angle will offer the best sound for the most seats.

COMMENTS
jeffhenning's picture

Having a great sounding room is more important than speaker placement.

Treating the walls and ceiling toward the front end of the room will pay more dividends than speaker placement. Of course, experimenting with speaker placement is is free and room treatment isn't.

To get a great sounding room, you need several things:

• First off, if possible do not use drywall on the walls and ceiling. It's terrible for acoustics. Wood is much better. If you use finish quality plywood, the walls have some give and absorb a good deal of the low bass. A lot of the room nodes in the low bass area don't exist.

• Using some type of treatment on the front half of the room on the walls and ceiling will take most reflections out of the sound of the room. It will improve the imaging immensely.

• I'm assuming that the floor is carpeted so, obviously, that helps.

• Adding something to the rear of the room that diffuses the reflected sound from the front will, with the proper set up, make it seem like you have a surround system even when you don't. In my case, it's some double door closets which I leave partially open. In front of them, I have 3 Boltz media racks with CD's and DVD/Blu-Rays. The combination creates a very diffuse reflection in the rear. It sounds fantastic.

• My theater is in a strangely shaped basement that seems to make the sound even better.

• The room has a drop ceiling with fiberglass insulation between the rafters above. Replacing 12 of the ceiling tiles with GIK Acoustics panels were transformative in improving the rooms sound.

Again, it's not free, but the ROI was off the charts. I was just very lucky with having a good sounding room to start.

Honestly, though, I've created great sounding rooms starting with rooms that don't sound nearly as good from the start. It does, though require more cost to do that.

DRB's picture

The other aspect with most rooms in people's homes are the ceiling height, and depth of the walls.

It's nice to know there are others that understand the difference between drywall and plywood. The other thing to do is to use deeper wall cavities. What walls are, are diaphragmatic absorption cabinets, but the problem is that the cabinet depth determines what frequency/frequency range it's going to absorb, along with how they are constructed and what type of fill material inside. There are some that do understand this and they design cabinets specifically to go after the low frequencies that cause modal pressure problems. One company I know of, actually uses typically 2x12 studs, they'll use any combination of materials including OSB, Finish grade plywood, MDF, MLV in between layers, and they'll use various thicknesses of activated carbon and they can actually effectively absorb even down to 30hz really well.

As far as how to treat the room? It's a combination of diaphragmatic absorption to go after the 100hz and below, then a really good mid-high frequency range absorption that has a nice smooth absorption coefficient curve between 125hz and 1000hz, and then quadratic diffusion. All of this has to be factored in along with the room dimensions and the room's usage. Home Theater vs 2 channel listening room may have different treatment and a different RT60 reverberation times..

But also the biggest issue is picking the right size speakers for the room. One of the biggest problems with small rooms is low frequency issues and what happens is that people don't generally have good room dimensions and/or proper room treatment, so it's common for people to buy sub woofers and have them turned up to a level where it's just overloading the room. it's better to have smaller speakers and better room treatment, especially with the low end. If you get the low end managed right, the rest is easy. But the room dimensions are critical. Low ceilings like 8ft are always going to have problems and you can't really add much treatment to the ceiling to help manage low frequencies, because they typically do have floor to ceiling modal problems. higher ceilings are always better, especially if you can add room treatment.

3ddavey13's picture

I have a similar setup. Basement HT, ceiling insulation so the sound doesn't travel upstairs, and a drop-ceiling using 2x2 Certainteed/Saint Gobain acoustic ceiling tiles (don't know if they're absorptive or reflective). The ceiling tiles do a good job as far keeping things quiet upstairs and don't seem to deaden the sound in my theater room, but if replacing some of the tiles with GIK Acoustics panels would improve sound quality, I'd like to give it a try. I was wondering if you could give me some idea how many panels I would need and where to place them (my ceiling has a 9 by 7 panel layout). I realize no two rooms are alike but having some idea of where to start is better than none.
Thanks
Dave

jeffhenning's picture

...in a pattern that looks like a big "H" above my chair. A column of four, two columns of two and another column of four.

I started with a half dozen to test their efficacy. Those did such a great job with the mains and center that I expanded it to cover the surrounds.

At the moment, I'm single so my theater is a solitary affair, but when this pandemic crap ends I will be ready to mingle so I'll have to get another chair and ottoman.

As to the regular ceiling tiles, they are probably both depending on the frequency. That's the reason that you just can't use any type of foam for room treatments.

Do keep in mind though that these have wood frames so they can be pretty difficult to get into place. I suggest to them that they reduce the width & length by a sixteenth inch or so because of this.

jeffhenning's picture

My approach was based upon the room which, honestly, is all you can ever do.

In this particular case, the low end was not a problem. I don't know if anything is between the plywood and the houses foundation, but, there may be insulation. The stud centers are pretty wide which seems to help a lot.

As to the ceiling, yes, the higher the better. Again, though, I lucked out and, while it's a hair less than 8', the GIK panels and the insulation above makes it sound like it's a lot further up.

As to the walls in the front, most of that is first covered with Markertek Sound Absorbing Blankets. I've also seen the same thing used as moving blankets. In front of that, I've hung thick curtains to dress up the room. All of that loosely hung, heavy fabric absorbs a tremendous amount of both the sound hitting the wall as well as the sound the wall makes by vibrating.

Again, this is a make-shift, LEDE set up that I'm fortunate enough to have work very well.

And, hey, RT60... when was that ever mentioned on this site? The dead end with the main speakers & subs is probably around 30mS or less. Spin around in the main chair and it's around 100-150mS.

It's funny when you walk into my theater. It started as a stereo rig with so much diffuse reflections at the rear that is almost sounded like surround. It's now a full blown 5.2 rig with 5 KEF LS50's and 4 Rythmik L12 subs. The stacked subs serve as stands for the left & right speakers.

And, again, the room sounds so great that I haven't had to consider speaker placement or use the Dirac Live in the XMC-1 pre/pro.

A few months ago, I had a writer at some lousy audio site tell me that the speakers were much more important than the room. Trying to explain the fallacy of his thoughts wound up being a waste of time.

I might as well have been trying to explain how HD video looked to a person that still had a 21" Sony Trinatron.

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