Specifications

Chapter 5: DigiRack Real-Time TDM and RTAS Plug-Ins 65
fast attack times and heavy limiting, you should
generally use a proportionally longer release
time, particularly with material that contains
many peaks in close proximity.
Release Controls how long it takes for the Com-
pressor to be fully deactivated after the input
signal drops below the threshold level. In gen-
eral, if you use heavy compression, you should
use proportionally longer release times in order
to avoid pumping that may occur when the
Compressor is forced to jump back and forth be-
tween compressed and uncompressed signal
levels. Lengthening the release time will help
smooth these changes in level by introducing a
lag in the ramp-up/down time of attenuation.
Use shorter release times on material with fewer
peaks that do not occur in close proximity to
each other.
Knee Sets the rate at which the compressor
reaches full compression once the threshold has
been exceeded. This control ranges from 0
(hardest response) to 200 (softest response).
Graph Displays the response curve set by the
Compressor’s Threshold, Ratio, and Knee set-
tings. As you adjust these controls, refer to the
graph to see how the shape of this curve change.
LFE Enable Enables plug-in processing of the
LFE (low frequency effects) channel on a multi-
channel track formatted for 5.1, 6.1, or 7.1 sur-
round formats on some plug-ins. To disable LFE
processing, deselect this button. For more infor-
mation on the LFE channel, refer to the Pro Tools
Reference Guide.
External Key Enables and disables side-chain
processing. Side-chain processing uses the vary-
ing amplitude of a separate reference track to
trigger compression. See “Side-Chain Process-
ing” on page 22.
Key Listen When enabled, this lets you listen to
the reference track controlling the side-chain in-
put. This is useful for fine tuning the Compres-
sor’s settings to the Key Input. Key Listen audi-
tions the right audio channel on RTAS and
AudioSuite versions of the Compressor.
Limiter II
The Limiter is used to prevent signal peaks from
ever exceeding a chosen level so that they don’t
overload amplifiers or recording devices. Most
limiters have ratios of 10:1 or 20:1, although
some provide ratios of up to 100:1. Large ratios
effectively limit the dynamic range of the signal
to a specific value by setting an absolute ceiling
for the dynamic range.
The Limiter’s ratio is internally set to 100:1, and
the Attack time defaults to 1 millisecond. The
Limiter is similar to heavy compression. It can
be useful for reducing pops and clicks, or for
hard-limiting dynamic range for broadcast or
band-limited mediums such as cassette.
Key Listen is not saved with the other plug-
in settings.
Limiter II plug-in