Surround sound systems can be very confusing, with all the different channel configurations and associated technologies. If you are in the market for a surround sound system and you need to break through some of the clutter we’ve put together a basic primer on surround that we hope will help, since surround sound is one of the best ways to improve the entertainment value of your big screen TV.
Main types of surround sound systems
The three main types of surround sound are 5.1, 6.1, and 7.1 channel. The numbers refer to the number of speakers that are required for that type of surround sound system. The first number before the “.” is the number of regular speakers and the number after the “.” is the number of subwoofers. So 5.1 refers to 5 speakers and one subwoofer; 6.1 is 6 speakers and one subwoofer, and so on. There are other permutations that you might see as well like 7.2, which means 7 speakers and 2 subwoofers (which you might need in a large room). The other feature of many 7.2 receivers is they can provide surround sound in one room and stereo sound in another room.
5.1 Channel Surround
5.1-channel surround is the most common home theatre configuration because it is the simplest of the three, will work in most rooms, does a great job creating a true surround sound experience, and is typically the least expensive. The two most popular types of surround sound in 5.1 systems is Dolby Digital and DTS. Dolby Digital is common in Movie Theatres. Each channel is discrete (i.e. independent from the other channels), which means the sounds can be placed around the room very precisely for some excellent surround effects. DTS is slightly better than Dolby Digital in that the sound is less compressed so it is a bit more accurate and realistic.
The 5 speaker channels include 3 in front (plus the sub) and 2 in the back of the room. There is an added centre channel in the front, in addition to the left and right channels.
6.1 Channel Surround
6.1-channel surround sound provides a slightly more enveloping surround sound effect than a 5.1 channel system because there is one extra discrete centre channel in the back of the room. This makes three speakers in the front and rear in addition to the subwoofer. The type of sound electronics for 6.1 systems is typically DTS-ES, Dolby Digital EX, and THX Surround EX. Most 6.1 surround receivers will accommodate multiple sound formats. Again DTS has less compression for a slightly clearer sound, but both formats will provide an awesome experience.
7.1 Channel Surround
7.1-channel systems are configured with 3 speakers in the front, one on each side and two in the rear, for the fullest surround effect. The 7.1 audio formats can be the most detailed as well, with Dolby TrueHD and DTS-HD Master Audio. Both of these are newer formats that have “lossless” surround sound which are not compressed and can therefore be identical to the original studio recording. Blu-ray discs support this more detailed lossless audio format for 7.1 systems.
The other formats for 7.1 channels are Dolby Digital Plus and DTS-HD, which deliver fully discrete channels for excellent surround effects, although these formats are not the high detail lossless sound mentioned above. Nevertheless, they are still excellent sound formats for awesome surround effects.
Dolby Atmos: bringing overhead channels to your home theatre
You’ve probably heard about Dolby Atmos. This system was first developed for movie theatres back around 2012. Essentially, Dolby Atmos creates 3D sound— where you “hear” sounds in a 3D space.
What is Dolby Atmos?
When you have a 5.1 or 7.1 channel home theatre sound system, you create the illusion of 3D sound by pushing specific audio to specific speakers.
With Atmos, instead of pushing sound to a particular speaker, it’s pushed to a particular spot in 3D space, sometimes by more than one speaker. Dolby Atmos also changes the game by adding dedicated overhead speakers, or upward-firing speakers to complete the sound cocoon.
To get the most from Dolby Atmos, you’ll need an Atmos-ready amplifier or receiver, plus front and rear speakers, and of course those overheads. But what if you don’t have the space or the budget for the full set up? There are Dolby Atmos modules that speaker manufacturers are making that can sit on top of existing speakers at the front of the room and can direct the sound up to the roof and then it bounce it back down into the room Or, look at some of the Dolby Atmos-enabled sound bars that are available.
Surround Sound basics
So which is better? Of course you will get a greater surround experience with more speakers, but the other factor is the size of room. If you have a much bigger room then you should get a bigger system (don’t mean to state the obvious). In a normal size family room, a 5.1 system will do great—you can get awesome sound with a true surround effect. I have a 5.1 system that I have been super happy with!
The nice thing is you won’t be disappointed by any one of these options, and it can really enhance your home theatre experience – even when just watching regular TV or sporting events.