The procedure of installing multi-channel audio speakers in home theater systems is rather tedious and vendors have invented new products and technologies including wireless surround sound speakers or surround sound wireless headphones recently to help simplify the setup. I will review the latest trends to understand which devices really work. I will also give some guidance for selecting the perfect components.

The majority of today’s TVs will be set up as a multi-channel audio system. Whereas historically TVs would have built-in stereo loudspeakers, today a number of external loudspeakers are used to let the viewer experience surround sound. While the traditional 5.1 format requires 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.

For that reason, home theater setups have turn out to be rather complicated. Running cables to remote speakers also is often undesirable because of aesthetic reasons. Several technologies have appeared to simplify this procedure.

One option is reducing the number of speakers by building virtual speakers. This method applies signal processing to the audio and adds phase shifts and cues to the audio that would usually be sent through the remote loudspeaker. The signal processing is engineered according to how the human hearing determines the location of a sound. The audio signal is then sent by the front speakers. The signal processing has an effect that will trick the listener into presuming that the sound is originating from a different position.

Virtual surround eliminates the remote loudspeakers and simplifies the setup and also avoids long speaker cord runs. Then again, it also has a disadvantage. The form of each human’s ear is somewhat different. Thus everybody processes sound in a different way. The signal processing of these virtual surround systems is based on a standard model which was calculated with a standard ear. However, virtual surround will not work equally well for each person.

Wireless surround sound devices are one more approach for simplifying home speaker setups and usually include a transmitter component that connects to the source and in addition wireless amplifiers which will connect to the remote speakers. The transmitter will normally come with amplified speaker inputs in addition to line-level inputs and come with a volume control to adjust it to the source audio level.

While a few wireless speaker systems come with a wireless amplifier that connects to two speakers, other devices offer individual wireless amplifiers for every speaker. The most sophisticated wireless devices employ digital transmission to avoid signal degradation. Be certain that you select a wireless system with a low audio latency, at most several milliseconds. This will make sure that the sound from all speakers, including the non-wireless speakers, is in sync. Low latency is also important for good sync with the video. A high latency would lead to an echo effect. This effect would deteriorate the surround effect. Wireless kits frequently utilize the 900 MHz or 2.4 GHz frequency band. Some products also use the 5.8 GHz band. These products have less competition from other wireless products than products using the crowded 900 MHz or 2.4 GHz bands.

A third technology uses side-reflecting speakers. This solution is named sound bars. The sound that would normally be broadcast by the remote speakers is instead sent by loudspeakers at the front. These front speakers broadcast the sound at an angle. Then the sound is reflected by the side and rear walls and appears to be coming from besides or behind the viewer. This solution works best in a square room with minimal interior design and obstacles. It will not function well in a lot of real-world scenarios with different room shapes though.

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