Apparatus for reducing distortion in a peak limited audio siganl. The amount of low-frequency spectral energy in the input audio signal is determined for a peak limited signal and used to control low-frequencies in the output audio signal. Identical low-pass filters with cutoff frequencies of 2.2 kHz are used; one passing a peak limited signal, the other a non-peak limited signal. When no noticeable low-frequency spectral energy is present in the peak limited (clipped) signal, the peak level is controlled below 2.2 kHz, without distortion, by a VCA and above 2.2 kHz by a clipper. When low-frequency spectral energy is present, the VCA reduces gain on each low-frequency wave to prevent uncontrolled safety clipping.
12 Claims, 4 Drawing Sheets