Euphonix MixView CS2000, Operation Manual

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Section 9: Dynamics
9 - 26 Euphonix CS3000/2000 Operation Manual
GainCurve, GainBall and
the Side-Chain
The GainCurve TM illustrates the relationship between gain reduction and side
chain level. The side chain signal (which is not necessarily the input signal)
always triggers the operation of the dynamic gain element. While it is com-
mon for the side chain to be fed directly by the input, this is not always the
case. Because of external keying and filtering options, the side chain signal
must be considered as a separate, independent signal. For this reason, the
MixView graphics show both input level (bar meter above the graph) and side
chain level (GainBall’s horizontal deflection) at all times.
Other manufacturers also offer graphical interfaces with their dynamics
processors, but these generally display output level versus input level, rather
than gain reduction versus side chain level. The Euphonix display is more
useful than other gain displays because it gives salient user feedback during
all modes of dynamics processing, even when the side chain signal differs
from the input signal as is the case with a ducker, keyed gate, or when side
chain filtering is used.
The Euphonix GainBall TM (patented) shows the real-time behavior of the
dynamics processor in a very clear and intuitive manner. The GainBall’s
horizontal deflection (X coordinate) tracks the detector level in the side chain,
while its vertical deflection (Y coordinate) tracks the gain reduction being
applied to the signal. The GainCurve acts as the “target position” for the
GainBall, for a given side chain level, while the time constants (attack, re-
lease, hold) cause the ball to stray from the curve as the target gain changes.
The more transient the signal and the longer the time constants, the more the
GainBall strays from the GainCurve. This is illustrated by the following ex-
amples.
For example, if you have made a gate with a fast gate release time, as the
input drops below the gate threshold the gain reduction will drop sharply
down to the -22dB level so the GainBall hugs the curve. If you increase the
release time, the GainBall leaves the curve as it takes more time for the gate
to “close”.
GainCurve and GainBall
Examples
Fast Gate Release Time Slow Gate Release Time