| 摘要 |
<p>The enhancement processor disclosed herein includes left (10) and right (11) channels through which the components of the stereo signal are fed, and a side channel (12) that receives a difference signal derivedfrom the main left and right channel signals. The side channel difference signal is shifted in quadrature, (e.g. + or - 90') relative to the main channels of the processor, adjusted by a variable gain control (17), low pass filtered (36) and added back (18, 20) into the main left and right channels prior to the stereo outputs. Further enhancement is achieved in the processor by combining with the above effect, a gain adjusted anti-phase cross-feed (30, 32) between the main left and right channels to produce an image-widening characteristic that compensates for some undesired image alteration resulting from the quadrature shifted side channel. An advantageous form of thecombined quadrature shifted difference signal and anti-phase cross-feed signals is provided by a single user controlled gang potentiometer that jointly and dependently vary the gain of these combined effects according to a unique control law described herein.</p> |
