Editing Dynamic range compression (section)

=== Ratio ===
The amount of gain reduction is determined by '''ratio''': a ratio of 4:1 means that if input level is 4&nbsp;[[decibel|dB]] over the threshold, the output signal level is reduced to 1&nbsp;dB over the threshold. The gain and output level has been reduced by 3&nbsp;dB. Another way of stating this is that any input signal level over the threshold will, in this case, be output at a level which is only 25% {{nobreak|(i.e. 1 over 4)}} as much over the threshold as its input level was.

The highest ratio of <math>\infty</math>:1 is often known as ''limiting'', and effectively denotes that any signal above the threshold is brought down to the threshold level once the ''attack'' time has expired.