Virtual Surround Sound Systems - Big Sound Without Big Speakers

The newest must-have for anyone with a TV and stereo these days is a home theater setup. As usual for our got-to-have-the-best society, most people think big when they dream of their ideal home theater. How big? You know, big screen television, big sound from a powerful receiver and amplifier, and really big sound from the speakers spread all over the room.

But, once the dream dissolves into reality, many of us realize that this big setup just will not work in our homes. We might not have the room for all those speakers. After all, 5 speakers and a sub-woofer do take up a considerable amount of space. Or maybe, we just do not want all those cables running around the base boards. Or, we do not want the technical hassles of setting up and balancing such a large system.

Fortunately, those with limited space or minimalist design ideas still have options. The appeal of surround sound can be addressed in a different way. Technology has stepped in and developed what is being called virtual surround sound. Virtual surround sound has been developed to mimic the sound characteristics of a multi-speaker system. Even though it uses fewer speakers and cables, a virtual system approaches the overall sound of a 5.1 or 7.1 amplifier and speaker system. There are two primary varieties of virtual systems, the 2.1 surround system and the digital sound projection system.

The standard placement for the 2.1 speaker system is to place two speakers in front of the listener, along with a sub-woofer placed somewhere inconspicuously in the room. The system will recreate the effect of a larger 5.1 setup that has 5 speakers and the sub. On the other hand, digital sound projectors will use a single strip of relatively small speakers to produce the sound. Most often, the digital sound system will not have a sub-woofer.

In either case, even though the setup is different, the same basic principle exists. The technology behind the system is based on a knowledge of how humans process sound internally. There are certain techniques used to modify the sound waves to fool the human ear into thinking that there are more speakers than what really are present. These techniques come from studies of psycho-acoustics, or the study of the way that people perceive sound. To fully appreciate what technology has done, you need to understand a least a little about psycho-acoustics, as well as physical acoustics (the science of sound).

Charles Moore is a technical adviser for Audio Equipment Speakers questions and specializes in addressing unique sound reproduction problems. He has an extensive background in live sound applications for various size venues, as well as the recording studio. He believes that the best performance in the world can be ruined with just a second or two of bad sound reinforcement. The proof of a well-designed sound equipment speaker application is that it is not even noticed by the audience. Invisibility is the ultimate goal.