How Virtual Surround Sound Works ?

There are several ways to surround yourself with sound. Some people have the space in their home and the money in the bank to install a great sound system with large-screen TV and speakers in several locations. In some cases, the speaker wires and cables can be hidden, especially if the surround-sound system is installed as part of room remodeling. Other people focus on the quality of sound and pay limited attention to the wires, speakers and other equipment.

Then there is the portion of the population that can’t afford a major system with many parts or don’t have the room to make that system practical. Now, with virtual surround sound, it’s possible to have the experience without the clutter of speakers and cables. In most cases, the expense will also be considerably less.

Virtual surround sound imitates the multi-speaker experience without the investment in speakers, cables and installation. Information from various sources shows there are two basic types of virtual systems – 2.1 and digital project. The first uses two speakers that project at the speaker while a low-frequency speaker commonly called a sub-woofer is located somewhere else. With virtual-surround technology this system provides the same room sound of a system with up to five speakers. Digital sound systems use a line of smaller speakers, often without the sub-woofer/low frequency speaker placed apart from the main speakers.

Essentially, these systems change sound waves so that the listener hears the sound as if it was coming from more than the minimal amount of speakers. A key factor in developing this type of system is new understanding of how people hear sound. Speakers convert electrical signals/impulses to sound waves that are sent into the air and to listeners. This is accomplished by the cone of the speakers, which pulses in and out, producing various levels of pressure.

The different pressure levels affect the ear, and the pulses eventually reach the brain as nerve signals or impulses. The brain can differentiate between spoken words, music and random sounds. We can also determine location and direction rather well, separating what is heard by the left ear and what is heard by the right ear. Unless the sound comes from directly in front of a person with two equal, perfect ears, the sound reaches one ear more quickly than the other by a split second. But the body also senses and reacts to sound. This is a key to understanding how the listener perceives where sound is coming from.

Some systems also use sound reflection, using room walls and other objects. With proper speaker placement and frequency levels, sound may seem to be coming from behind the listener, providing the semblance of surround sound. Other systems use a phenomenon known as cross-talk, which uses random sound to reduce or eliminate the difference in sounds heard by one ear over the other.

Successful use of virtual surround sound depends on the listener sitting in the right location and looking directly at the viewing screen to enhance the experience. It’s also important to adjust the system to the room size and room shape, using careful distance measurements and sound measurements to determine placement of the speakers.

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