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Multi-channel audio has become mainstream and vendors have developed many types of basic and more sophisticated technologies including wireless surround sound speakers, virtual surround sound to simplify the setup of home theater products. I am going to take a look at several of the newest technologies that were designed to make setting up home theater systems a breeze. I will highlight what to look out for when making your buying decision.

Historically, setting up a TV would be swift since they would already have built-in stereo speakers. This, though, has all changed with multi-channel audio. These days external speakers are used to create a surround sound effect. As the traditional 5.1 format needs 6 speakers: a front center, two front side speakers, two rear speaker and a subwoofer, the more modern 7.1 format adds two additional side speakers.

Therefore setting up a home theater has become rather complex and long speaker wire runs are often undesirable for aesthetic reasons. A number of technologies have appeared to simplify this process.

One option is reducing the quantity of loudspeakers by creating virtual loudspeakers. This approach applies signal processing to the audio and adds phase shifts and cues to the sound that would normally be broadcast by the remote loudspeaker. The sound is next sent by the front loudspeakers together with the front speaker audio components. The signal processing is modeled after the human hearing. It uses the knowledge about how the human ear can determine the origin of sound. The signal processing has an effect that will deceive the listener into presuming that the sound is coming from a different location.

The benefit of this technology is that only a couple of loudspeakers are needed and no long speaker cable has to be run throughout the viewing environment. The disadvantage however is that each human will process sound differently because of the different form of each human ear. Since the signal processing is based on a standard human ear model, virtual surround will not function equally well for everybody dependant upon how much the viewer differs from the standard model.

An alternative approach for simplifying home theater installations and eliminating long speaker cable runs is to make use of wireless surround sound devices or wireless loudspeakers. A wireless solution will typically incorporate a transmitter component that connects to the TV or source as well as wireless amplifiers that will be connected to the remote loudspeakers. This transmitter will usually provide line-level in addition to amplified speaker inputs. Ideally it should come with a volume control to adjust it to the audio source.

Some wireless speaker kits are designed to connect 2 speakers per wireless amplifier. A superior solution would provide a wireless amplifier for each remote loudspeaker to get rid of the cord runs between each of the 2 remote loudspeakers. Entry-level wireless devices utilize FM transmission or audio compression which will deteriorate the audio quality to some degree. More sophisticated wireless products employ uncompressed digital audio broadcast. In multi-channel audio products, it is crucial to pick a wireless option with a latency of only a few milliseconds. This will ensure that the audio of all loudspeakers is in perfect sync. A high latency would lead to an echo effect. This effect would degrade the surround effect. A few wireless products work at 5.8 GHz which offers the advantage of less competition from other wireless devices than systems using the crowded 900 MHz or 2.4 GHz frequency band.

A different method, which is often referred to as sound bars uses side-reflecting loudspeakers. There are additional loudspeakers located at the front which broadcast the audio for the remote loudspeakers from the front at an angle. The sound is then reflected by walls and appears to be originating from besides or behind the viewer. The result heavily depends on the interior, especially the shape of the room and the decoration. It will work well for square rooms with no obstacles and sound reflecting walls. However, realistic scenarios frequently will be different from this ideal and diminish the result of this approach.