Positioning speakers correctly is important if you want to get the best sound out of your Home Cinema speaker system but it doesn’t have to be hard!
What is 2.0, 5.1 and so on
In surround sound, we refer to two types of sound channels:
- Main or full-range channels which normally reproduce a frequency range between 80Hz and 20KHz
- Low Frequency Effects (LFE) channels – or subwoofers – which reproduce anything below 80Hz
in the X.X notation, the first number refers to how many full-range channels there are and the second number refers to how many low-frequency channels there are. For example, in 5.1 there are 5 full-range channels and 1 LFE channel.
The symbol displayed on some DVDs and Blu Rays for 5.1 surround sound encoded on the disk
Channels versus Speakers
We refer to channels when we talk about how many sound channels are put onto a medium such as DVD, Blu Ray or TV broadcast.
We refer to speakers when we talk about how many speakers reproduce the sound that is being played. For example, did you know that you can play stereo (2.0) channels over a 5.1 speaker system and vice versa? An explanation of why and how to do that is going to be a topic of another post. For now, let’s position your speakers in your listening environment.
7.1 Surround Speaker Placement
Front Left and Right Speakers – 2.0
This is real easy! You simply place the speakers on the left and right of you TV screen. All you need to ensure are two things:
- They are ear height when you’re sitting down – unless you’re watching movies standing up for some reason!
- If they are more than two meters apart, ensure the speakers are slightly turned inwards towards the listening position so they end up facing you.
Centre Channel Speaker – 3.0
The centre channel should go in between your front left and right speakers. Usually the best place for it is under or on top of your TV. Unfortunately, doing either could compromise dialog intelligibility. To avoid this, experiment with the following:
- Try placing the speaker both under and over your TV screen and see which position you prefer in terms of sound
- In each position, angle your speaker up or down to ensure it is firing towards your ears as you sit down in your normal listening position. To achieve this, you may need to wedge something under the bottom front or bottom back of the speaker to get the right angle. One way to do this is to buy some rubber stick-on feet like below on ebay and use those.
Surround Speakers 5.1, 6.1, 7.1
Now this is a bit more tricky but it becomes easy as long as you know how many surround speakers you want to install.
2 surround speakers for a 5.1 set-up – Surround Left and Surround Right
If you have two surround speakers, it is best to position them as follows:
- Height: about 1/2 to 1.5 meters high from your ears when you’re sitting down
- Best Placement: about 1/2 meter back from where you are sitting to the left and right of you. This can be on the wall or on speaker stands or even hang them from the ceiling. You don’t need to have them at equal distance from you, so you could put them on the side walls even if your room layout is not symmetric AS LONG AS you account for this when you set up your AV receiver. I will show you how to do this in my next post.
- Good placement: if you cannot position the speaker high or behind you, you can position them on speaker stands to the side.
3 surround speakers for a 6.1 set-up – Adding 1 Surround Back Channel
All modern AV receivers can process stereo and 5.1 channel (dolby digital and DTS sound-tracks) to extract 6.1 and even 7.1 channels. This provides a more stable surround sound stage and better movement (called steering) of sound effects at the back of the sound stage.
When you add a third surround speaker, you will need to:
- Put it behind you on the wall or on a speaker stand at the same height as your Surround Left and Surround Right speakers.
- Set your AV Receiver to mono Surround Back channel or 6.1 Speaker Configuration and ensure you connected the speaker to the correct speaker terminal. Most AV Receivers will ask you to connect a single Surround Back speaker to the Left Surround Back Speaker terminal.
4 surround speakers for a 7.1 set-up – Adding Surround Back Left and Surround Back Right Channels
You can also have stereo Surround Back channels, adding two speakers behind you instead of just one. To achieve this, you will:
- Put both speakers behind you at the same height as the surround Left and Right Speakers.
- Leave a minimum of 1/2 meter distance between them. The bigger your listening area, the bigger the space between them should be. For example, I use all my living room as my listening space so the surround back speakers are placed equal distance from each other and from the side walls.
- You can measure your listening environment and make the same calculation: equal distance from each other and from the side of your listening area such as your couch while still respecting the minimum distance between the two speakers (1/2 meter).
Subwoofer – the .1 in X.1
Subwoofers can go anywhere in the room because the sounds they produce are non-directional – that is you cannot tell where they are coming from. Subwoofer placement is an art in itself and short of hiring an audio engineer, you can do a lot to get the best sound in your room with the following rules:
- If you have only one place where your subwoofer can go, then easy: place the subwoofer there.
- If you can put it both front and back, try it in the front of the room first then try it at the back and see which position sounds best.
- If you can literally put it anywhere, and you just want to get THE BEST sound possible, you can do the follow – called the crawl test:
- Place your subwoofer in the position where you normally sit. This may require shifting the couch and putting the speaker on a chair.
- Put your favourite music track on with a lot of consistent base.
- Now crawl around the room and mark any places where you consistently like the sound of the base – these are the “sweet spots” in your listening room.
- Place the subwoofer in one of those “sweet spots”
In spite of the above rules, first and foremost you should always trust your ears. Play with speaker placement and see – or rather hear – what sounds best to you!
There is no discussion about “virtual sound fields” as provided in Yamaha receivers..which leads me to ask how a 6.1 array would effect steerable sounds in an action movie?
That’s a very good question, George. Apologies for the late reply, just noticed this.
I haven’t tested 6.1 myself with Yamaha, however, most likely the back surround field would be mixed into both the back surround speaker and the side surround speakers. I would at least recommend having the front height speakers installed, though, as they are more important to create a wall of sound at the front. Yamaha is very good at creating virtual surround at the back as only their top end receivers in any line allow for back height speakers in addition to the surround and surround back speakers. All the others create the height information using the back channels as well as the front heights if they are attached.
Thank you for your response. Since posting last I have experimented with virual effects on and off. I enjoy directional sound i.e. if the speeding train enters the scene from the left your attention is directed to the left both from video and audio cues. In virtual mode with NO presence speakers added all sounds are blended. there is some direction but no comparison to effects without virtual. Further Yamaha implies that if presence speakers are in the array and rear speakers are too the virtual effect may not be in play. Yamaha is not clear in its instructions. When I posed the question to their techies they insisted I use the 3D. Period. Real world sound is truly directional and Yamahas attempt to immerse the listener in some sort of pool of sound mystifies me and seems to direct its sales to 2 speaker arrays. Music is a different story and that may be why Yamaha has gone to such great lengths in creating virtual audio effects.