Qu Mixer Reference Guide
32
AP9372 iss.9
Gate
The Noise Gate can be switched in to dynamically turn
off the audio when it drops below a certain level. For
example, to reduce resonant decay of a kick drum or
floor tom, or hiss of a noisy keyboard.
Use the In key or screen button to switch the Gate in
or out. This is similar to inserting an outboard rack
mounted device into the Insert socket on an analogue
console channel.
Set Depth for how much signal reduction you want
when the gate closes. 20dB is a typical setting. The
GR indicator lights and red screen meter shows the
amount of reduction when the gate is closed.
Hold sets how long the gate remains open after
dropping below the threshold. Attack sets how fast the
gate opens when the signal rises above the threshold.
Release sets how fast it closes when dropping below
the threshold. Experiment with these controls to
achieve smooth operation without a pumping effect.
HPF
(high pass filter)
The HPF is used to reduce unwanted low frequency
sounds such as vocal popping, wind noise and stage
rumble.
Switch the HPF in using the In key or screen button.
Use the panel rotary or screen button and rotary to
sweep the cut-off frequency until you have reduced the
unwanted sound. The filter has an 18dB slope and can
be swept from 20Hz to 2kHz. The violet screen curve
shows the resulting frequency response.
PEQ (parametric equaliser)
The Parametric Equaliser allows tonal adjustment of
the channel sound. It provides independent control of
4 frequency bands, each with three parameters that
can be adjusted:
LF (low frequency)
LM (low mid frequency)
HM (high mid frequency)
HF (high frequency)
Gain – Boost or cut frequencies by up to 15dB. Centre
0dB is flat response (no affect).
Frequency – Each band can sweep its centre point
frequency across the full range from 20Hz to 20kHz.
This means you can overlap bands and have more
precise control over problem frequency areas.
Width – Each band has a bell-shaped response. The
width of the bell can be varied from a very wide 1.5
octaves affecting many frequencies to a very narrow
1/9
th
octave affecting a small range of frequencies.
Setting LF or HF to widest position using the screen
rotary changes its response to shelving.
Experiment with the controls to hear their affect on
different sounds. Switch the PEQ in or out using the In
key or button to compare the sound. For live mixing it
is better to cut rather than boost frequencies where
possible.
Note
– The lower part of the
Gate meter is a darker green
to show signal ‘noise’ level
below -40dB.
Gate active
GR = Gain Reduction
You can turn the PEQ graph fill on or off
using the
Setup / Control / Preferences
screen.
