Manual

22
2.3.8.2 Linear/dB timing (Linear type)
The Linear /dB law, in some respects, exhibits the reverse behaviour of the Exponential law.
Because the rate of change of gain is constant (as set by the timing controls), the greater the
signal dynamic excursion the longer the compressor will take to complete a gain change.
Also, since the total time that the compressor spends in attack or decay is proportional to the
size of the gain excursion, the harmonic content of the compression artefacts will seem to
reduce in frequency content the louder the signal excursion is. This type of compressor is
useful for generating dynamic audio effects because the sonic character of the compression is
much more affected by time control settings and programme material than the exponential
type.
The diagrams above illustrate the action of the linear law. The first shows 10dB gain
reduction (scaled for comparison) and the second one shows 30dB. The rate of change is the
same during the attack period, and therefore the total time for attack (and subsequent release)
is increased with greater level transition.
Please note that the Linear timing law is generally unsuitable for the control of
programme dynamics and modulation levels because of its unnatural sounding
relationship between level excursions and perceived overtone generation.