When thinking of a home theater, many of us think that we should have a big screen where we can get a bigger picture and a set of multiple speakers and a big sound which fills up the home. Typically, the home theater system consists of the surround sound system with sub-woofers. This is not possible in all homes since probably the area within which the sound travels is not big enough. Many people like to avoid having to adjust many of the speakers to get an exact sound each time. This is the case with surround sound which copies or reproduces the same sound of the speakers.
There are two types of prime surround sound – this is the 2.1 projection system consisting of a couple of speakers placed before a listener with a sub-woofer in the same room, elsewhere. The base principles are the same wherein many methods to modify the sound originating from a few speakers is set to seem like come from many more speakers. So, a virtual sound system taking benefit of the principle of sound and hearing- of compression and rarefaction of the air around the speakers to produce the effect of many sets of speakers. This enables the sound to travel in long waves.
The brain also plays an important part trying to recognize the high as well as low pressured waves. When these waves reach your ear, it recognizes these sounds as nerve impulses put together as a sentence and includes tone and rhythm. Aural cue is given to the brain and along with the sound waves properties help you in deciding where the origin of the sound is and how one can perceive these.
Creating of virtual sound that gives a surround effect is using Dolby mechanism or method. It uses an algorithm and creates again the emitted sound as a surround feature. The brain gets a clear assessment of the sound produced into the left or right ear. The path of the sound that is elevated takes a different route to the ears. Sometimes you find it difficult to decipher if a sound is coming from the front or back depending on ILDs and ITDs. The brain is able to use the reflecting of the sound wave to the external ear to assess the location of the sound.
Therefore, the sound that reaches your body reflects of your body parts making a different sound of each. Also, each of these reflected sounds will be different based on the origin of the sound whether from the back or from the front of you. Researchers use the HRTF (Head Related Transfer Function) factors of the brain’s shape to decide the origin of the sound in your room. Waves bounce several times before reaching the tympanic membrane of your ear.
Scientific studies reveal that by attaching mikes to different parts of the body, they can determine the sound reflected of different parts of your body. Then the computer was used to analyze the effect of such sound reflection. So, this means that aural cues are applied to a sound wave and fools you to think that the sound is from one origin. This gives a virtual surround effect. So instead of interpreting that the sound is coming from 2 speakers, the mind is deceived in thinking that there are 5 speakers producing the sound.
