What is surround sound? What is meant by 5.1? What types of systems are available? All these questions will be answered in this article!
What is Surround Sound?
Surround Sound quite simply is the use of multiple speakers to make it seem to the listener that he or she is surrounded by the events making sounds. It can make it seem like you’re in a concert hall hearing the instruments echoing around you, or hearing the sounds of the jungle surrounding you in a movie. There are a number of different technologies in use to make surround sound a reality, but what’s really most noticeable to the user is the speaker layouts and effects that come with them.
The list of layouts below is far from comprehensive, but covers the most commonly available ones.
Not as common these days, but the first Dolby Pro Logic systems had 4 channels plus the subwoofer(the .1). These 4 channels were Left, Centre, Right and Rear Surround. The rear surround would be located behind the main listening area.
Probably the most common type of setup, introduced with Dolby Pro Logic II. Most modern Dolby Digital content on DVD and Blu-ray is also designed for 5.1. The 5 channels of 5.1 are Left, Centre, Right, Surround Left and Surround Right. There is also a subwoofer channel. In a 5.1 set up the the surround speakers should be directly to the left and right of the main listening area.
7.1 channel surround sound systems were popularised around 2005-2006 with several low cost consumer systems made available. The 7 channels of 7.1 are Left, Centre, Right, Surround Left, Surround Back Left, Surround Right and Surround Back Right. There is also a subwoofer channel, in some cases even 2 to produce a 7.2 channel system. The surround speakers would be placed directly beside the listener, with the surround back speakers placed centrally a few metres behind the listener. So for a 7.1 set up you require a much bigger room than for a 5.1 setup. Another disadvantage of 7.1 is that not a lot of movies are produced for 7.1 surround sound so there’s no real benefit to the extra speakers.
Some systems claim to be able to produce surround sound with just 2 speakers. These systems rely on special processing to make your ears think the sound is coming from different directions. In practice they don’t tend to work that spectacularly and the sound quality is not that great.
Types of Systems
There are a few different types of home theatre/surround sound systems available in the market today. I’ll discuss the two main types:
Dedicated Surround Sound Receivers
The best way to get surround sound for your home theatre is to have a dedicated surround sound receiver. This is a dedicated device just for sound in your system. They have connectivity for all your audio-visual devices and will act as a hub for them all, connecting them to your TV and speakers. In this day and age I would only suggest getting a surround sound receiver that has HDMI. You can use HDMI devices with an older style surround sound receiver, but then you’ll need to switch video and audio separately. This can be harder to use.
Blu-ray/DVD Home Theatres
A popular option over the last decade has been the integrated Blu-ray or DVD Home Theatre unit. This is a Blu-ray or DVD player with a built in surround sound decoder and amplifier. The idea being you have one less box to install in your set up. These systems are quite reasonable for many people who just have simple set-ups. If all you want to use your surround sound for is movies it’s fine. The issue comes with the lack of connectivity. There’s simply not many places to plug your other devices into them.
Most of these home theatre systems will accept audio from your TV. However if you wanted to get audio from a media device such as an Apple TV box, this would have to go via the TV. Not all TVs will forward this audio on to the home theatre box. Another example is if you have a DVD Home Theatre unit and want to connect a Blu-ray player to it. You could connect the Blu-Ray player to the TV via HDMI, and hopefully the TV will send the audio back to the DVD Home Theatre, but depending on how it connects you may not have the highest quality. Alternately you’d have to get a whole new Blu-ray Home Theatre system.
I most cases I would recommend a home theatre component system with a dedicated surround sound receiver. A 5.1 speaker system is fine for most homes. Unless you have a special room set up, 7.1 will not be worth it. What to look for:
- As many HDMI sockets as possible
- At least 1 or 2 composite AV inputs
- At least 1 analog stereo input for devices like Digital Radios
- Larger speakers tend to be better quality than smaller ones
Don’t be swayed by large numbers quoted for wattage of sound output. The biggest number doesn’t necessarily mean better. A higher quality, noted by signal to noise ratio and frequency response is a much more important means of choosing a system. Also when setting up your system don’t turn the Bass control on the subwoofer to maximum. Most home theatre systems have way too much bass, so a character on screen shutting a car door ends up sounding like a nuclear explosion!