Speaker placement: back to the basics
This week we want to take you back to the basics of speaker placement for a home theatre set-up. We’re not talking about Atmos or subwoofer placement, although there are plenty of things to be said for both. We just want to keep it at a very low-key ‘here’s where you start’ level when you take the next step up from a sound bar, although there is no harm for more advanced readers in refreshing the ‘level 1’ info. For people wanting further information, we have referrals to more advanced blogs on several topics that are interlinked.
The reason for that is simple end we’ve said it time and time again: it’s so much better to do a good quality well done 5.1 system than a 9.2.4 set-up that is full of short-cuts and compromise. Do the basics as well as you can and allow/plan for upgrades in the future.
Here goes…
When we talk about a 5.1 set-up, this means 5 speakers and a subwoofer: the left and right front channels for the stereo as well as the main left and right front effect, the very important center channel for the main soundtrack and dialogue and 2 side surround speakers for surround effects. You can extend that to a 7.1 system (add left and right surround back channels) or even Dolby Atmos at a later stage. If Atmos takes your fancy, we have covered this in a previous blog. If you are building or doing extensive renovations, we do recommend to pre-wire for Atmos.
This brings us to the next question: what speaker placement is optimal? In this case we will assume a nice rectangular home theatre, which we realize is kind of an ideal situation, but let’s start with the beginning.
Setting the distance between the front left and right loudspeakers is a trade-off between a wide soundstage and a strong centre image. The further apart the loudspeakers are, the wider the soundstage will be. As the loudspeakers are moved further apart, however, the centre image weakens, and can even disappear. If the loudspeakers are too close together, soundstage width is constricted.
The ideal speaker separation will produce a strong centre image and a wide soundstage. There will likely be a position where the centre image snaps into focus, appearing as a stable, pinpoint spot exactly between the loudspeakers.
There are a few ways to determine the best spot to place your front left and right speakers. The more elaborate but very precise way if you get it right is use a musical selection with a singer and sparse accompaniment for setting loudspeaker spacing and ensuring a strong centre image. With the loudspeakers fairly close together, listen for a tightly focused image exactly between the two loudspeakers. Move the loudspeakers a little further apart and listen again. Repeat this move-listen procedure until you start to hear the central image become larger, more diffuse, and less focused, indicating that you’ve gone slightly beyond the maximum distance your loudspeakers should be from each other for a given listening position.
If you don’t want to spend the time trying to find the right position of your front speakers, there is a very simple but effective rule of thumb: Dolby recommends an equilateral triangular placement for the front left and right speakers. This means the speakers are placed equally away from the listening position.
Both these processes are good if you have a single seat in the home theatre. Most often there are more seats and you really want to provide a great listening experience for the entire audience. The solution is to choose very good quality front left and right speakers with very uniform dispersion. This means that the sound is very consistent and you need very little toe-in for speakers like this (Toe-in is pointing the loudspeakers inward toward the listener rather than facing them straight ahead), guaranteeing that every seat in the home theatre is a good seat.
If you use bookshelf speakers, you want to put them on speaker stands so the tweeters sit at ear level when sitting down. Yes, it really makes a big difference.
The centre channel needs to be placed in the centre of the screen, at ear height.
Some people like to place their front speakers behind the projector screen. If that is your choice, make sure you place them as close as possible to the screen so you have as little diffraction as possible. It is good to be aware however that there will always be some loss of high frequency detail, but it definitely pays to opt for the best possible screen you can afford to avoid this. These days there are screens on the market with minimal distortion.
When choosing front and centre speakers you want to opt for the same brand for these 3 speakers so they provide very similar acoustical properties and tonal characteristics for seamless transition in panning and a much more natural blend.
Surround speakers are placed very differently in the room so while it is nice to have the same brand, it is not as crucial as with the front speakers. That said, you do want to make sure that the surround speakers provide very similar dynamic capabilities. Remember, your home theatre is only as good as it’s weakest link.
Unlike the three fronts, the surround speakers are used to create a cloud of non-localized sound that envelops the viewer. Side speakers are best placed beside or a few feet behind the main seating area and a few feet above ear level so the surround sound is not too easy to localize.
If you prefer a diffuse sound field, bi-pole (in phase)/di-pole (out of phase) surround speakers are the way to go. If your choice is to have more localized information, we recommend monopoles. With more and more people choosing to also have rear channels, monopoles tend to be the more popular option these days. We have a blog on mono-pole, di-pole and bi-pole speakers from about a year ago if you are interested in more info on this topic.
Rear surround channels in a 7.1 set-up are placed again a few feet above ear height and slightly closer together than the front speakers.
For our tips on subwoofer placement we again refer you to a previous blog as this one is already becoming too extensive and frankly, subwoofer placement is kind of an art on its own.
While it is important to start at the basics, we have dedicated a blog in the past on how to deal with not so ideal room lay-out and other complications. Because let’s face it, not everybody has the luxury of having a state of the art home theatre set-up.
In the meantime, give us a ring or send us an email if you need help with your special set-up requests. We love to work with you towards the best possible solution.