| 摘要 |
In Multi-channel Sound systems for cinemas, left and right channel signals are conventionally matrixed with a surround signal to form two signals which are recorded on a stereo bilateral variable area sound track. On playback the original signals are recovered by a matrix decoder 12. The left and right signals LF and RF (and optionally a derived centre signal CF) are applied to respective loudspeakers. The surround signal feeds loudspeakers at the back of the cinema but is delayed (delay 22) by about 75% of the sound path length from front to rear of the auditorium. This suppresses perceived cross-talk from the left and right signals to the surround loudspeakers. <IMAGE> |
