The output of a compressor whose gain reduction is brought in progressively over a range of input signal values, such as over 10db or so, starting a few dBs below the threshold.. When the input signal amplitude comes within the range of the threshold, the compressor starts to apply again reduction, but with a very low ratio setting. As the input level increases, the compression is automatically increased until, at the threshold level, the ratio becomes infinite. Compare with hard knee compression.
