Cedar AZX+, Owner'S Manual

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OPERATING THE BRX+ DEBUZZER
Introduction
CEDAR
’s buzz and hum removal process uses information about the fundamental
frequency and the overall volume of the buzz or hum to identify, up to a limit of
4kHz, all the harmonics that constitute the noise. It is left to the user to determine
how much of that noise is then removed.
Fundamental frequency
Your first job will be to identify the fundamental frequency of the buzz or hum.
This is accomplished most easily by setting the
PROCESS
button to
ON
and then
rotating the
BUZZ POWER
and
ATTENUATION
knobs to their maximum values (fully
clockwise). There may be artefacts such as a ‘comb-filtering’ effect at this point.
You can safely ignore these because they are a consequence of the over-
processing being applied by these maximum settings.
Note: If the buzz is very low in level compared with the rest of the signal, you should
initially set the
BUZZ POWER
to ‘12 o’clock’ rather than to maximum.
If the fundamental frequency is set wrongly then the process will not be able to
identify the buzz.
The
FREQUENCY
knob has three modes of operation: preset value selection, fine
continuous adjustment, and coarse continuous adjustment. You may select
between them as follows:
Q
Preset selection
The preset frequencies represent the most commonly encountered
fundamental frequencies. You can select between these by pressing the
FREQUENCY
knob and keeping it depressed while you rotate it.
In cases where the true fundamental frequency does not lie precisely on
a preset frequency, you should use the
FINE
adjustment mode to adjust
the value.
Q
Fine adjustment
Pressing and releasing the
FREQUENCY
knob toggles between the
COARSE
and
FINE
(0.01Hz below 100Hz, 0.1Hz above 100Hz) adjustment modes.
The
COARSE
and
FINE
indicators in the
FREQUENCY
display will tell you
which mode you have selected.
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