Inovonics David IV, Инструкция по установке и эксплуатации

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Audio levels are measured and monitored in many different
ways. The traditional mechanical “VU” and European “PPM”
(Peak Programme Meter) each adhere to rigid measurement
standards. But there are many knock-offs and alternative level-
indicating gizmos as well, few of which have traceability to any
recognized standard. These meters may have floppy mechani-
cal movements or take the form of LED and other bargraph
readouts, or can even be on-screen computer displays.
Standardized or not, all these devices have their own response
to, and provide their own representation of, program peak and
average levels. What’s more, board operators lend their indi-
vidual interpretations to what they see, assuming that they are
even paying attention to console meters in the first place.
Adjusting
Input Gain
Return to the
Setup / Audio Input
menu:
Next, turn the jog wheel to position the brackets around the
Digital Gain or Analog Gain slider, whichever is appropriate to the
input you have selected. Push the jog wheel to enable that slid-
er so that you can then turn the jog wheel to dial-in the re-
quired gain.
With program material playing, adjust
Digital Gain
or
Analog Gain
so that the front-panel AGC gain indicator (the
AGC/GATE
LED
bargraph) hovers around
0dB
most of the time. This will show
that AGC action is more or less centered and working in its
‘sweet spot.’
AGC is a slow, long-term gain-riding function. You cannot rush
this step as there will be a delay of many seconds before the
AGC meter settles-down each time the slider is adjusted.
There will, of course, be a range over which the AGC wanders, it
is not possible to have it hover right at the
0dB
mark all the
time. But the indicator should spend about as much time above
0dB
as it does below.
The dB gain numbers shown below each input gain slider are
somewhat arbitrary, but have been scaled so that 0dB equates
to the program average level at nominal studio line level fig-
ures. This is on the order of +4dBu for analog inputs and
–20dBFS for digital inputs. For example, a well-tempered
+4dBm program line would suggest an Analog Gain setting of
–4.0dB
, and digital program levels with a typical headroom al-
lowance of 20dB (relative to 0dBFS) would need a Digital Gain
figure of
0dB
. Again, the scaling holds true more for actual
program material than for steady-state tones.