Ashly mXa-1502 Operating Manual page 18

mXa-1502 • Operating Manual
Parametric Equalizer
The PEQ parametric equalizer offers a variety of
useful filter types for adjusting signal response
with greater precision. A master on/off button
enables/disables the PEQ block.
10 individual filters are available per PEQ block,
each filter capable of the following types:
Parametric, high-shelf and low-shelf at 6dB/
octave or 12dB/octave, all-pass, variable-Q
high-pass and low-pass, notch, and band-pass.
Individual filters have an on/off setting.
Select a filter number first, then choose a
filter type, then adjust by dragging its control
node, using the slide-controls, or by entering
parameter values in the text boxes to the right
of each control.
PEQ Parameters:
Filter 1-10: filter On/Off, active selection
Ashly AquaControl™ Software
Filter Types:
• Parametric: Symmetric boost/cut, allowing
individual adjustment of center frequency,
level and bandwidth.
• High-Shelf: Asymmetric boost or cut with
"shelving" shape. Allows adjustment of the
corner frequency and amplitude. Slope
can be selected as 6 dB/octave or 12 dB/
octave.
• Low-Shelf: Mirror-image of high-shelf.
• All Pass: Provides no change in amplitude,
but adds -180° phase shift at the corner
frequency.
• Notch: Infinite cut at specified center
frequency, with adjustable bandwidth or Q.
• Variable Q HPF: Second order high pass
filter with adjustable Q.
• Variable Q LPF: Second order low pass filter
with adjustable Q.
• Band Pass: This will pass signals within the
filter's response region. It allows adjustment
of center frequency and bandwidth/Q. Gain
is 0 dB at the center frequency.
Frequency: Selected filter center/corner
frequency.
Level: Selected filter boost/cut amplitude.
Bandwidth: Selected filter bandwidth (or Q). .
Filter Type Details
Parametric EQ Filters
Parametric EQ uses peak filters with the ability
to control boost or cut, frequency center, and
bandwidth. Think of one band of parametric EQ
as a single graphic equalizer fader, except that
the frequency is variable, and the bandwidth,
or how "wide" the filter affects the frequency
spectrum at the center frequency, is also
variable. The smaller the bandwidth, the less
the audio signal on either side of the frequency
center is boost or cut, whereas a larger "wider"
bandwidth produces an audible change to the
overall tone of a signal.
Parametric filters are best used to hunt down
and eliminate problem feedback frequencies,
add or remove a characteristic "hot spot" from
microphones, or clean up room resonance
situations. It is well worth the time becoming
proficient with parametric EQ filters, as they
offer the best solution to many EQ problems.
Parametric filters have a boost/cut range
of +15dB to -30dB. There is more cut than
boost because one of the more common
uses for parametric filters is to dramatically
cut, or "notch out", very narrow frequencies
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