All you need to know about 5.1 surround sound systems

In today's market, as we go out to see the speakers and home theater products, lot of us come across the term 5.1, 7.1, 5.2, 7.2 channel home theater or we hear surround sound systems. But, what is it actually? A home theater system is a replica of a theater like sound system. The distinguished sounds and effects that we hear in the theater can be reproduced at your home with a home theater system. A home theater system comprises of normal speakers and woofer(s).

A 5.1 channel home theater means it has 6 different channels of sound output. A normal stereo has 2 channel output namely left and right channel. Many times when you have plugged in your headphones or earplugs in your computer to hear your most loved song, you come across some effects where you hear some sounds only in the right ear or some sounds are played only in the left ear. This effect is called panning. Similarly, in a cinema or theater movie, there are lot of such effects. Sometimes, while we are watching the movie, we hear some claps, chorus or some effects come from behind us. This is the surround sound effect.

Basically, a 5.1 channel home theater has 6 speakers placed in your room in such a manner that you can experience the theater like environment at your home. There are 6 speakers in a home theater system namely (Front right, Front left, Rear right, Rear left, Center and Sub Woofer). The front speakers generally produce the music and other sounds in a movie. The center speaker is responsible for all the dialogues and voices that you hear in a movie. The rear speakers produce chorus and other special effects. The sub woofer produces the BASS.

So, the next time when you are out to buy your home theater you shall know what kind of speakers you are buying. For example, if you are buying a 5.1 channel surround sound system, you are buying 5 normal speakers and one sub-woofer. If you are buying a 5.2 surround sound system, you will get 5 normal speakers and 2 sub-woofers.

Things you must know before buying the 5.1 surround system system

1. Rating of all speakers
2. Rating of center speaker
3. Rating & Range of sub woofer

By checking the rating of any speaker, you have to see the power (given in watt) of each speaker. If you are buying a cheap 5.1 surround sound system you shall find the power of the center is almost same as other speakers. So, the problem that you shall face in near future is that while you are watching movies in surround sound, the dialogue and voices will not be heard very clearly. To hear them clearly, you will have to raise the volume of your system quite high. Raising the volume high should not a concern but problem that you will face by raising the volume high is that when suddenly in the movie there are musical or sound effects, you will feel that the volume of your system is too high and you might find those sounds distracting. The reason for all this mentioned above is that because your center speaker cannot produce more power so you higher the volume of your system which actually raises the volume of entire system and hence, when there is scene of fight or some special effects there will be lot of sounds produced from the system and you will feel that the volume is too high because you have been listening to the dialogue. To summarize, normal dialogue and speech will appear calm and other sounds will appear very high.

To save this from happening, see the demo of the surround sound system and look out if you can individually set the volume level of each speaker. If the system allows you to individually set the volume on all the speakers, it is a good system to be purchased.

See the range of the sub woofer, it should be given in hertz. Generally a system can produce lot of sounds. The range of a system is given with the upper and the lower limit like (50~20000Hz) or so on. Check out the range your system, the higher the range, more sounds will be played on your system. Like for example, if your system is capable of playing sounds from 500Hz~20000Hz, you will not be able to hear the deep bass when something is going into the water or the first note of a bass guitar because these sounds are generally around 200Hz or even lower and your system is not capable of playing them.

Next, we shall see what volumes should be kept on your surround sound speakers. I am rating these speakers on the volume scale of -5 to +5.

Front Right - +1

Front Left - +1

Rear Right - +2 or +3

Rear Left - +2 or +3 (same as rear right)

Center - +5 (while watching movie) and +1 while listening to music

Subwoofer - +5 (if you love the bas) or 0 (to hear normal bass)

The above given volume levels are taken into considerations that you can sit anywhere in your room, Generally to get the best effect out of your surround sound system, you should be seated in exactly the center of your room or in other words in we speak technically you should be equidistant from each speaker (excluding the sub-woofer). A sub woofer can be placed anywhere in the room, but keep in on a lower level, generally directly on the floor.

Lastly, you need surround sound movies, which are available in all the DVD and blu ray formats. If you are playing from a pen stick or your USB Hard disk drive, check out if your movie has a 5.1 channel audio format or not.

Please note: some systems are capable of upscaling a normal 2 channel audio to 5.1 channel, but it will not sound that great as an original 5.1 audio.