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.
Thomas J. Norton
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