The process of setting up multi-channel audio speakers in home theater products is fairly tedious and manufacturers have invented new products and technologies including wireless surround sound speakers or surround sound wireless headphones recently to help simplify the installation. I will look at various of the most recent technologies that were designed to make installing home theater systems a snap. I will illustrate what to look out for when making your buying decision.
The majority of recent TVs will be installed as a multi-channel audio system. While traditionally TVs would come with built-in stereo speakers, today a number of external speakers are used to allow the viewer experience surround sound. As the traditional 5.1 format needs 6 speakers: a front center, two front side speakers, two rear speaker and a subwoofer, the more recent 7.1 format adds two additional side speakers.
Therefore setting up a home theater has become pretty complex and long speaker wire runs are normally undesirable for aesthetic reasons. Several technologies have emerged to simplify this procedure.
The first approach is building so-called virtual speakers by applying signal-processing to the sound and introducing phase shifts and special cues to those audio parts that would typically be broadcast by the remote loudspeakers. As the signal processing is based on how the human hearing detects the origin of sound, the audio components which underwent signal processing can be mixed with the front speaker components and sent by the front loudspeakers. The viewer is in effect deceived into assuming the audio is coming from a location other than the front speakers.
The benefit of this technology is that only a small number of speakers are needed and no long speaker cable has to be run throughout the viewing environment. The disadvantage though is that each person will process audio in a different way as a result of the different form of every human ear. The signal processing of these virtual surround systems is based on a standard model which was measured with a standard ear. However, virtual surround will not function equally well for each person.
An additional option for avoiding long speaker cord runs is to make use of wireless surround sound devices or wireless loudspeakers. A wireless kit includes a transmitter and one or a number of wireless amplifiers. The transmitter connects to the source. The wireless amplifiers connect to the remote loudspeakers. This transmitter will normally provide line-level and amplified loudspeaker inputs. Ideally it should come with a volume control to adjust it to the audio source.
Several wireless products have wireless amplifiers that connect to two loudspeakers. This still requires wire runs between the two loudspeakers. Other products offer individual wireless amplifiers for every speaker. The most advanced wireless devices use digital transmission to eliminate signal degradation. To be certain that all loudspeakers are in sync in a multi-channel application, be sure that you pick a wireless system that has an audio latency of a few milliseconds at most. Otherwise there will be a noticeable echo kind effect. Most wireless devices operate in the 900 MHz and 2.4 GHz frequency bands. A number of products use the less crowded 5.8 GHz frequency band and as a result have less competition from other wireless gadgets.
Another approach are side-reflecting speakers. These products are also known as sound bars. In this case the audio for the remote speakers will be sent by separate loudspeakers positioned at the front at an angle and reflected by walls as to appear to be originating from besides or behind the viewer. The effect heavily is dependent upon the interior, especially the shape of the room and the decoration. It will function well for square rooms with no obstacles and sound reflecting walls. On the other hand, realistic scenarios often will be different from this ideal and reduce the effect of this solution.
Posted under Miscellaneous Content
This post was written by admin on August 19, 2010
