Even of you are only marginally aware of the science and art of speaker placement, you have probably heard that an equilateral triangle formed between the left and right speakers with the listener’s head forming the apex of the triangle is the optimal setup. You’ve also probably heard that toeing in the left and right speaker at a 60° angle is going to help develop the best soundstage. The former is still a best practice, but KEF’s Uni-Q technology has pretty much made the 60° toe-in obsolete, which is an immense help when setting up your speakers for the optimal listening experience for multiple people. You may find a bit of toe-in helps, maybe on the order of 10° or so depending on room size and listening distance, but the old 60° speaker angle has (happily) gone the way of the 8-Track.
There are still some guidelines you should follow for setting up your speakers for the best soundstage and imaging. There are no perfect rooms, and everything in the audio world always boils down to a bit of a compromise, but speaker technology (like Uni-Q), and amplifier and DSP technology can almost eliminate most common problems. If we’re aware of the compromises that may have to be made, we can work around them.
One: Fire Lengthwise
If your room is rectangular, set up your speakers and television against one of the short walls and have the speakers fire into the longer dimension of the room. This is especially true of subwoofers. It takes time for soundwaves to setup and the more room you provide them (especially with lower frequencies) the better the result.
Two: Think in Terms of 3rds and 5ths
It is no coincidence that music is based on 3rd and 5th intervals and that you should also think of speaker setup in those same mathematical terms.
The optimal primary listening position is typically 38% of the room distance from the wall the speakers are set up on. For example, if your room is 10 feet long, the optimal listening position would be 3.8 feet, and for a room that is 16’ long the distance would be 73” or approximately 6 feet. But hang on a minute, because there’s another measurement you need to take into account…
Three: Positioning Speakers From the Wall
We’re still thinking in terms of 3rds and 5ths when we figure out how far from the wall we need to place our speakers.
If your room is 16’ long (192”) the ideal distance from the wall is approximately 38” to 63” from the wall. Again, ideally isn’t always achievable: certain destructive standing waves may develop at distances between 39” and 86” inches depending on a couple of factors, so you may have to experiment a little.
If your room is 8’ wide then you should start by placing the speakers 19” or 32” from the wall, and experiment from there.
Here’s the formula for speaker distance from side walls:
W * .2 = Dmin
W * .33 = Dmax
W = Room Width in inches
Dmin = Minimum distance from closest speaker edge to side wall
Dmax = Maximum distance from closest speaker edge to side wall
Here’s the distance for speaker distance from the wall behind the speaker:
L * .2 = Dmin
L * .33 = Dmax
L = Room Length in inches
Dmin = Minimum distance from wall to rear of speaker cabinet
Dmax = Maximum distance from wall to rear of speaker cabinet
Four: Equilateral Is the Goal
With all of this in mind, we want to come as close to an equilateral triangle between the Left and Right speakers and the main listening position. With Uni-Q we don’t have to be as precise with this measurement as we would with non-coincident speakers, but it’s still a good practice to come close.
In our example of the 8’x16’ room we would set up our speakers like this:
Minimum distance from rear wall: 38.4” (192” x .2)
Minimum distance from side wall for left and right speakers: 19.2” (96” x .2)
Minimum distance from wall to seating area: 73” (6 feet): (192” x .38)
Starting from here, we would do our calculations in 3rds or 5ths for setting different wall-to-speaker and seating area distances. It may seem confusing, but it’s not once you get the hang of it, and remember – these are just guidelines, your mileage may vary depending on windows, doors, furnishing styles, need to actually live in the room and other things that will force us compromise between the optimal audio-video experience and living in the space.
Five: Speaker Positioning In Relation to Your Television
The center channel speaker will produce up to 70% of the audio program from a surround sound mix. Getting the center channel speaker setup right is the key to how your theater system will sound.
Obviously, it’s a center channel speaker, so the place to start is having the center of the main speaker lined up exactly with the center of your television screen. For example, if your center channel is a D’Appolito design then line up the center speaker in the array to the center of your television. You may get unlucky, and your room dimensions, furniture of physical environment may cause destructive standing waves to set up between the center and left or right (or both) speakers. If you’re having trouble hearing certain sounds, or the dialogue seems garbled or low sometimes, then move the speaker slightly from its center position either left or right. This asymmetry may help kill off any standing waves, but keep in mind – if you move it too far, you’re going to be distracted by sounds that are supposed to be coming from the center of the screen that are coming from the side.
Since we have to get our Left and Right speakers set up in proper relation to our side walls, the actual placement of the television on the wall is also critical. Ultimately, you want the center speaker directly above or below the physical center of the television, and you want the Left and Right speaker to be equally distant from the center channel. Of course, for proper imaging you want the Left and Right speakers to be slightly outside of the perimeter of the television – how far to the side will depend on room dimensions, television size and all of the things we covered in section one through four.
The tweeter, or HF driver, should be at – or as close as possible to – ear level, so you’ll need to take the vertical plane into account when designing your setup.
You want to get as much sound and video as you possibly can get out of your room without getting the sound and video out of balance. It can be tricky, so if you’re ready to drop a bunch of money on a system and you’re not exactly sure how to get the most out of your equipment and/or room, consulting with a qualified system designer may be your best bet (keep in mind, we haven’t even spoken about surrounds or Atmos speakers, or subwoofers – this was all just for the front three channels!