De-Esser; Output - Focusrite ISA 430 MKII User Manual

automatically displays the gate sidechain listen level when a
Listen switch is pressed in (see Metering section, page 3).
Range
Range determines how much the signal is attenuated when
the gate is closed. The gate can be set up to cut (80dB
attenuation, control clockwise) or to more gently lessen
attenuation (min 0dB). Maximum attenuation may give an
unnatural sound, so keep Range at a low value unless it is
essential to reduce high levels of background noise, or
unless an obviously gated effect is desired.
Threshold
Threshold determines the level at which the gate opens (or
at which gain reduction finishes when in Expander mode).
The higher the threshold, the more low-level noise is
reduced, and the more extreme the effect.
Hold
Hold controls the variable delay before the gate release
starts. This allows the gate to be held open until the signal
has decayed sufficiently, so that the rapid onset of gain
reduction isn't noticeable. Alternatively the signal can be
deliberately truncated before its natural end to create a
special effect.
Release
This control sets the Release time, the rate at which the
gate attenuation increases, fading out the signal. This release
period begins as soon as the signal drops below the
threshold. On transient signals, a fast release will be
appropriate (control anticlockwise), but with other material,
a slower release (control clockwise) may give a more
natural sound. Ideally the release needs to be slightly slower
than the natural decay rate of the signal to avoid audibly
cutting it short.
Fast Attack
Fast Attack determines how quickly the gate opens once
the level of the source signal has risen above the threshold.
When the switch is pressed, the response is fast, which may
be necessary on some signals to avoid "missing" an initial
transient, but which could also introduce an undesirable
click on smooth, sustained sounds when using a high
threshold setting. On such signals a slower attack (switch
released) may give a more natural sound.
Hyst
Press to introduce wider hysteresis. This increases the level
difference between the gate switching on and off, which
prevents the gate from oscillating ('chattering') with
particular combinations of input signal and threshold setting.
This function is particularly useful when gating a signal with
a very long decay time and large amounts of level
modulation (e.g. a grand piano).
Ext Key
Pressing Ext Key switches control of the gate to an external
signal on the rear panel GATE KEY INPUT jack.

De-Esser

The de-esser uses an optical design, allowing the user to
remove excessive sibilance from a vocal performance
(where "ess" sounds are over-emphasised).
De-Ess In
Press in to activate the De-Esser.
Threshold
Threshold determines how much de-essing is being applied
to the selected frequency. The lower the threshold (control
anticlockwise) the more de-essing is applied.
Freq
This control selects the frequency to be removed; between
2k2Hz and 9k2Hz.
De-Ess Listen
Press to allow monitoring of only those signals which will
trigger activation of the de-esser, rather than hearing the
overall effect in a complex full bandwidth signal. The Listen
LED below the main VU meter illuminates to show that
'Listen' mode is active. Note that the VU meter
automatically displays the de-ess listen level when the Listen
switch is pressed in (see Metering section, page 3).
Active LED
The Active LED illuminates when the de-esser is active at
the chosen frequency, and shines more brightly with
increasing level reduction.
Setting up the De-Esser
Press De-Ess Listen with Threshold at maximum and slowly
reduce until the selected frequency begins to trigger the de-
esser. Vary the frequency control to find the exact area of
the signal which you wish to remove. Once located, switch
off De-Ess Listen and adjust Threshold for the amount of
reduction required. No further adjustment of Freq should
be required, as the hot spot will have been precisely found
using De-Ess Listen.

Output

9
Ext Sum
Press to route a sum of both the
internal signal and external line input
signal (from the EXT SUM INPUT) to
the Main Output. External signals could