User Manual

DF330 OPERATOR’S MANUAL
5
CONTROL DESCRIPTION
A 'Traffic Light' LED meter monitors input level at -6dB, 0dB and
+6dB.
HIGH PASS FILTER
50Hz Hi-Pass
When switched to In, this filter affects both the signal path and the
side chain detector circuitry. It may be used to remove subsonic
material from the programme being processed and has a slope of
18dB per octave. It also prevents high levels of extremely low
frequency signal from opening the filter.
EXPANDER SECTION
Threshold
The expander threshold is continuously variable from -50dB to
+10dB. The amount of gain reduction taking place is shown on a
five section LED meter.
Ratio
A three position switch allows expansion ratios of 1:2, 1:5 or 1:20
to be selected.
Release
The expander release time is user variable from 0.05s (50ms) to 5
seconds.
In/Out
Permits the expander to be bypassed independently of the filter
section.
Attn.
Attenuation of the expander is controlled by a three position switch
with options of -10dB (the least effect), -20dB or -40dB (maximum
effect).
A five segment LED display shows the expander gain reduction.
FILTER SECTION
Man/Auto
Switches the filter section to Manual or Auto Mode. In Manual
mode, the filter frequency depends on the level of the input signal
as well as its frequency. In Auto, the filter frequency is influenced
essentially by the frequency content of the signal being processed
and not by its level.
Threshold
In Manual mode, the Threshold control determines how the filter
tracks the incoming signal level. Signals above threshold tend to
increase filter frequency whilst lower levels tend to close the filter.
Clockwise rotation sets a lower threshold level which opens the
filter.