THE Japanese consumer electronics company JVC claims to have developed a system that fools listeners into hearing sounds as if they are surrounded by loudspeakers, although there are only two speakers in the room. But the com pany has delayed the system鈥檚 launch after objections from Dolby Laborato ries. JVC鈥檚 digital 3D-Phonic system uses the five channels of sound generated by Dolby鈥檚 Pro Logic decoder, which was designed to feed five loudspeakers. 3D-Phonic processes these signals so that just two speakers can produce a similar effect.
The company planned to launch 3D-Phonic in Europe this summer, and wants to use the Dolby name to promote the system. But Dolby objected, saying that 3D-Phonic does not do justice to Pro Logic technology, and although Dolby cannot stop JVC selling the system, it can stop the company using Dolby鈥檚 trademarks. JVC has cancelled the launch, and the two companies are now trying to agree a solution.
3D-Phonic simulates the effect which is experienced when the left ear hears only sound recorded by a microphone to the left of an orchestra, and the right ear hears only sound recorded from the right. When sound is heard from loudspeakers, the left and right halves usually get mixed up, destroying the effect.
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JVC compensates for this mixing by bleeding a little of the signal from each speaker into the other, with the bled sound slightly delayed. This means that its vibrations are out of phase with the same sound from the other speaker, so they tend to cancel each other out. This effect can only be heard in an area of the room known as the 鈥渟weet spot鈥�. JVC says that this area is large enough to contain a three-person sofa, but Dolby argues that the need to sit in a sweet spot is too limiting.
