Klark Teknik HELIX DN9340E, Руководство оператора

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Operation: DN9340E
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6.6. Metering
Comprehensive audio metering is provided by eight LED bargraph meters:
There are a pair of input meters (labelled “A” and “B” for audio channels A and B,
respectively) that show the input level immediately following the input gain
control. These can therefore be used as a guide for setting the input gain to
match the signal level being sent to the unit. With the input gain control set to
0dB (unity gain) then full-scale on the meter will occur at a signal level of
+21dBu, which is the maximum permissible signal level. The input meters
incorporate a red ‘clip’ LED that indicates signal clipping both on the actual input
to the unit and also after the gain control. This ensures that all possible clip
conditions are monitored irrespective of the setting of the gain control.
There are a pair of output meters (labelled “A” and “B” for audio channels A and ,
respectively) that the output level from the unit. Full-scale on the meter indicates
maximum output from the unit, which corresponds to +21dBu. The output meters
also incorporate a red ‘clip’ LED. This indicates signal clipping within the unit, and
is monitored at all internal points where gain can be applied. Thus, if a large
amount of gain is added with one section of a parametric EQ, resulting in a clipped
signal, but the level is then reduced by a subsequent EQ section, the clip LED will
still illuminate to indicate the internal clip condition despite the apparently safe
output level. In this situation the input gain should be reduced to provide
sufficient headroom for the desired EQ characteristic. Note that because these
meters are on the output of the unit, they will show the effect of any delay that
has been selected.
There are four meters which show the action of the dual - threshold
dynamic EQ system - one meter for each EQ section on each of the two audio
channels A and B. The dynamic EQ meters are calibrated in percentage terms,
from 0 to 100. If no dynamic EQ is selected or if the signal is below the ‘low’
threshold, then the meters will show 0% (that is, no LEDs illuminated). Under this
condition the dynamic EQ will be using the ‘low’ frequency response settings. If
the signal level is above the ‘high’ threshold, the relevant meter will indicate 100%
(fully illuminated) showing that the ‘high’ EQ settings are now being applied. If
the signal is between the two thresholds, then the EQ will be morphing between
the two EQ settings, and the meter indicates the signal level relative to the two
thresholds. Note that the effect of the attack and release controls is also indicated
on these meters - the height of the bar indicates the actual EQ being applied, so if
a slow release is set, for example, you will see the meter drop back slowly
following a peak.