If you are thinking about setting up surround sound speakers in your room, then there are two main ways to go.
You can buy an AV receiver and some separate speakers, or you may want to investigate an all-in-one HTiB home theater system.
Whichever way you decide to go, it is important to understand the different speaker configurations that are available for your home theater setup.
Any one of these speaker layouts will enable you to improve on the sound you get from the built-in speakers on your display - and you will find the difference is amazing - but you'll need to decide the best speaker location and layout for your room before you go and buy the equipment.
The location of the speakers is crucial to any of these speaker layouts.
If you don't take time to think about the placement of the speakers, then you won't get the best out of your system - and you may even buy the wrong thing for your room.
In this article we will look at the main types of speaker configurations that are used in home theater today - mostly for surround sound speakers but also for other types of speaker layout.
You may find that one type of speaker setup will suit your room better - or it may simply come down to your budget.
Do you have a sound system to play music? This is probably a stereo system.
We all know what stereo is right?
Two speakers - one for audio left and one for audio right.
This can also be called a 2.0 system. The '.0' just means this type of system doesn't use a subwoofer.
Most music and TV programmes come with stereo sound.
If you do have a good stereo speaker system at home, you may be able to use this for your home theater sound. If you have an amplifier for your hi-fi that has a spare audio input - then connect the audio output from your programme source (eg. DVD player) into this.
Bingo! That's improved the sound already.
Although most people assume that home theater sound should be surround sound - don't forget that most audio on TV is still broadcast in stereo - and every DVD will have a stereo mix of the soundtrack.
Whilst it's great to have a surround sound system - you can get a really good quality stereo amplifier and speakers for the price of a mid-range surround sound system.
Your stereo TV and DVD audio will sound fantastic - plus you'll have a system which will sound great for listening to music too!
2.1 stereo sound is similar to a 2.0 stereo setup - with two speakers for stereo left and right.
The difference is that we also have a subwoofer speaker connected to the system too.
If you see any speaker configuration with a '.1', then this means it has a subwoofer.
A subwoofer is a speaker dedicated for bass frequencies. Most hi-fi speakers sound ok for mid-range and high frequencies - but many can't reproduce the low frequencies that well (although large floor standing speakers can give a good bass sound).
A subwoofer fills in the bass end much better and creates a better balanced sound. It makes a huge difference to the sound if you get a good bass along with the mid and high frequencies - and can make a big difference with movies with some of the special effects.
You may want a 2.1 speaker setup if you are happy with a stereo system (maybe you haven't the space to have more speakers in your room) - but you feel your current 2.0 hi-fi system doesn't give you enough bass.
You will need an amplifier/receiver that has a dedicated subwoofer output channel in order to get a 2.1 setup. However, there is a potential problem with this as there aren't that many standalone stereo amplifiers with a subwoofer output - although there are a few if you look around like the Harman Kardon HK 3770.
If you can't find a suitable stereo receiver with sub output, then your other options are to buy a 5.1 AV receiver and just connect it to a front left/right pair and subwoofer - or to buy a home-theater-in-a-box-system (HTiB).
A few all-in-one home theater systems come with a 2.1 speaker configuration and these can be an easy way to improve the sound in your room and beef-up the low-end.
If you haven't got enough space for a full surround sound speaker system, then a good compromise can be a 3.1 speaker system.
A 3.1 setup is the same as the previous 2.1 layout, but it adds a centre speaker to improve the sound for movies.
When you setup your AV receiver, you can tell it you don't have surround speakers at the rear, and it will play a 5.1 soundtrack minus the rear effects. The advantage over a 2.1 setup is the extra centre speaker will allow greater separation of voices and music, and so should improve the clarity in a busy soundtrack.
Surround sound! You've just gotta love surround sound. This is where it gets really fun with home theater speaker systems. If you haven't heard it in action then you must.
A 5.1 speaker system is the standard surround sound setup for home theater.
Pretty much all DVDs and Blu-rays will have a 5.1 surround sound soundtrack these days (as well as a stereo mix too) - and a movie will sound fantastic if you've got a good 5.1 speaker system in the room.
A 5.1 surround sound installation has six speakers in total.
Front left and right (which is the equivalent of your stereo speakers), front centre (mainly used for dialogue), surround left and right (it's behind you!) and a subwoofer (for bass).
You'll need an AV receiver which has five outputs to connect the center, front left, front right, surround left and surround right speakers. It will also have a subwoofer channel (sometimes called an LFE) to connect to your sub.
The AV receiver is sent the digital audio signal from the DVD/Blu-ray player - and the receiver then decodes it and sends the audio to the correct speakers.
When this speaker setup is connected to a good AV amplifier then the results can be superb. If your system is well balanced, a good 5.1 mix will really make you feel part of the action.
The sound should completely immerse you in the movie - with a mixture of music and sound effects that completely surround you.
Did I tell you I think surround sound is great? If you're not sure what speakers to buy, take a look at my guide to the best speakers for surround sound systems.
7.1 speaker systems are very similar to their 5.1 counterparts - but there are two extra speakers at the rear.
The purpose of the extra rear speakers is to get even more control over the sense of space in the room.
Many new AV receivers come with enough output channels to connect a 7.1 system, however you don't need to connect all seven outputs if you don't have the space (or enough speakers!), so you can use these in a 5.1 configuration too.
The biggest issue with 7.1 surround sound is that not many movies are mixed with a 7.1 soundtrack (although there are a few) - so you may wonder what the point is.
Well, a 7.1 AV receiver will have some digital audio processing modes where it will fill the extra speakers with sound from the 5.1 soundtrack - so giving the illusion of more space.
Therefore you will still get the benefit of having two extra speakers in the room.
You will generally need a bit more space in your room to connect a 7.1 sound system - the extra rear speakers really need to be behind the seating area - so that's going to be tricky if your seat is pushed back against the wall!
However, given enough space in your room to position your speakers correctly - a 7.1 system can give you an even better surround sound experience than 5.1.
More and more AV receivers now support this type of surround sound speaker layout.
A 7.2 speaker system is the same as a 7.1 setup - except it has two subwoofers - hence the '.1' being increased to '.2'.
A 7.2 surround sound receiver would therefore have two subwoofer outputs rather than the usual single one.
The main reason to have a second subwoofer is to even out the bass sound throughout your room - as the long wavelengths of bass sound waves can create standing waves in your room, which can lead to areas of quiet or loud bass.
Now, this isn't a situation we want in our home theater as it is obviously better to have a consistent level of bass regardless of where you are sat in the room.
Therefore, if we place a second subwoofer somewhere else, then we should be able to fill in the gaps and create a more even spread of the bass sound.
Obviously, you can also use this second subwoofer in a 5.1 surround sound setup too - and you will create your very own 5.2 surround sound system!
Another advantage of a '.2' system is you shouldn't need to drive two subwoofers as hard as you would with just one to get a good bass level, which may result in a better, less overdriven sound.
Whatever the reason for using two subwoofers, the speaker positioning would vary from room to room depending on the acoustics - and so it is impossible to say exactly where you should position your second subwoofer.
However, it may just be a simple case of having one near the front, and one near the back or side of the room.
As the bass sound from a sub is not directional, it shouldn't matter too much where you place the speakers, it is just the overall bass cover that you are concerned with.
Go to this article for more on subwoofer speaker placement.
So as you can see, you have a few options when deciding how to improve the sound in your home theater system.
A stereo 2.0 or 2.1 configuration is probably going to be best if you have limited space in your room - however you won't get surround sound with this setup (apart from using various digital audio processing tricks which try to create the effect from two speakers).
If you're interested in setting up a surround sound system, then your main choices are a 5.1 or a 7.1 system.
The 5.1 system is the most common - and most DVDs and Blu-rays will have a 5.1 soundtrack.
A 7.1 system creates an even better surround sound experience - but it requires more space to position the speakers properly and there are very few true 7.1 soundtracks.
If you need more detailed information about setting up surround sound, and the placement of the individual speakers, then start with the article on home theater speaker placement.