摘要 |
In a surround-sound encoding system which does not have full circular or square symmetry, a third channel is added to a basic two channel system in such a way that the third channel may be reduced in amplitude or restricted in frequency without substantially affecting important localization criteria. The encoder includes a phase-amplitude matrix such that a decoder having a phase-amplitude matrix which is the inverse of the encoder phase-amplitude matrix is such that the absence of the third channel signals at the input thereof does not affect localization in at least three, preferably six, predetermined directions. |