Software Instruction Manual

IQ–MSD Turbo 1.4 Advanced IQ System Software
Page 143
6.4.1 Gate Function
(Figure 6.9) “Gating” is one of the most important functions. It shuts off inputs that are not in use. Gating is often used
to prevent feedback. If several mics in a system are on at the same time, the system’s gain could become so high
that it rings with transients, or breaks into feedback.
Lowering the overall gain is one way to fix this problem, but some mic levels might become too low. Gating is a
better solution. A microphone is “live” only when a sound is loud enough to open its gate (for example, speaking,
singing, etc.).
Max Gain: The Max Gain control sets the maximum gain for an input. The gain can not rise higher, even when
the Auto level function is active. The Max Gain control also sets the “gate open” gain when only the Gate function
is in use.
When ASA is on, the Max Gain settings in the sub-block override the corresponding control block gain settings.
They work like the control block gain settings when most of the automatic functions are off. When ASA is off, the
control block gain settings take over.
The Max Gain control has its own “emergency mute” feature. Pressing the “Space Bae” when a Max Gain control
is selected immediately mutes the gain (sets it to –100 dB). This feature is a toggle. If the control is still selected, press
the “Space Bar” again to toggle back to the previous setting. The previous level setting is lost if the cursor is moved
to another control.
Tip: The final gain settings are usually made by listening. If you set the gain too high, the system could break
into feedback. It is possible to attenuate all channels at once using the secondary mix capability of the control
blocks. First, set the control block levels far below the feedback point. Now ASA can be used to activate the
control block mix which will pull all inputs below the feedback level. (The Max Gain To Track Control Block control
should be turned off.) The ASA control can be toggled on and off from the Sub-block screens by pressing
C+a.
Note: Toggling ASA on and off switches between the sub-block mix and the control block mix. This provides two
mixes
only if Max Gain To Track Control Block is not turned on.
IMPORTANT: The Max Gain control is
not intended to be adjusted in “real time” while the ASA control is turned
on. Instead, use the DAOL (Desired Average Output Level) control of the Auto Level function. The new level will
not take affect until the Reaction Time setting of the Auto Level function has transpired.
Low Set: The Low Set gain is the “gate closed” gain. Low Set is off by default (about –100 dB). Set it higher
if you want the signal to be audible even when the gate is “closed.”
Gate: The Gate function is turned on and off with the Gate control. Turning the Gate control off also turns off the
Duck Priority and Gate Count functions.
Threshold: The Threshold control determines when an input gate opens. When a signal exceeds the
Threshold, the gate opens causing the gain to increase from the Low Set value to the Max Gain value. When a
signal drops to the Threshold or below, the gate closes and the gain drops from Max Gain to the Low Set value.
Note: If the Threshold is set too high, the gate will never open, or only open sporadically. If it’s too low,