摘要 |
A peak-limiting apparatus and method particularly useful in systems employing high frequency pre-emphasis to compensate for steep high frequency rolloff in a receiver, or the like. The apparatus and method is useful in standard AM broadcasting to maximize loudness without noticeable distortion. The distortion caused by a clipper is determined by subtracting a clipper's output from its input. This distortion is compared in a plurality of critical bands with the input to provide a gain control feedback signal for a variable gain stage. The psychoacoustic phenomenon of "masking" is used to estimate maximum (non-audible) clipping.
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