Specifications

Audio Plug-Ins Guide86
Impact Attack Control
Attack sets the compressor attack time. To use
compression most effectively, the attack time
should be set so that signals exceed the thresh-
old level long enough to cause an increase in the
average level. This helps ensure that gain reduc-
tion does not decrease the overall volume. The
range of this control is from 0.1 ms to 30.0 ms.
Impact Threshold Control
Threshold sets the decibel level that a signal
must exceed for Impact to begin applying com-
pression. Signals that exceed the Threshold will
be compressed by the amount of gain reduction
set with the Ratio control. Signals that are below
the Threshold will be unaffected. The range of
the Threshold control is from –70 dB to –0 dB.
A setting of –0 dB is equivalent to no compres-
sion.
Impact Release Control
Release controls the length of time it takes for
the compressor to be fully deactivated after the
input signal drops below the threshold level. In
general, this setting should be longer than the
attack time and long enough that if signal levels
repeatedly rise above the threshold, they cause
gain reduction only once. If the release time is
too long, a loud segment of audio material could
cause gain reduction to persist through a low-
volume segment (if one follows). Setting this
control to its maximum value, Auto, selects a re-
lease time that is program dependent, based on
the audio being processed. The range of this
control is from 20 milliseconds to 2.5 seconds.
Attack
Threshold
Release