Panasonic 744T User Manual

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Metering 
23
Metering 
The 744T features a 76 LED (4 x 19) output meter. The DSP-controlled output meter provides a selec-
tion of ballistics and lighting intensities. In addition, peak indicators on input channels show clip-
ping activity. 
Output Meter 
0 dBFS track LEDs are programmable 
as peak LEDs 
(0 dBFS to 
−20 dBFS) 
 
The meter uses energy effi cient LEDs which are viewable in full sunlight. The 744T output meter is 
unaffected by shock or extremes in temperature and humidity. Meter ballistics are setup menu select-
able among VU, Peak, Peak-Hold, VU + Peak and VU + PeakHold. 
The meter uses a non-linear metering scale which increases meter resolution in the most important 
part of the  scale. From 
50 to 
40 dBFS, each LED segment equals approximately 10 dB. From 
40 to 
12 dBFS, each segment equals 2 dB. From 
12 to 0 dBFS each segment equals 4 dB. 
Meter Ballistics 
 
 
The output meter can be set to display any of fi ve types of meter ballistics:  VU, Peak, Peak-hold, 
a combination of VU and Peak, and a combination of VU with Peak-hold. The meter ballistics are 
selected in the setup menu. 
VU - (Volume Units)
 
Ballistics correspond closely to how the human ear perceives loudness and provides a good visual 
indication of how loud a signal will be. In VU mode, the attack and decay of the meter signal is 
300 mS. While giving a very good visual indication of perceived loudness, VU meters gives poor 
information on actual signal peaks and are virtually useless for tracking to the 744T. In VU mode, the 
front panel meter labeling is in volume units. 
Peak
 
Peak-reading ballistics correspond to actual signal maximums, but don’t necessarily correspond to 
perceived signal loudness. A peak meter has a near-instantaneous attack to display maximum signal 
amplitude and a slow decay to allow the user to see them. Peak metering is essential for digital re-
cording, since signal overload can cause immediate distortion. The peak meters front panel markings 
are calibrated in dBFS, decibels relative to full scale digital signal. 
Peak Hold 
Essentially the same as Peak metering where the peak level indication will hold for the peak level 
indication for several seconds. Peak-hold indicators are useful for metering in applications when an 
overload condition is unacceptable. 
Peak/VU 
The meter can simultaneously display VU and Peak level information. In this mode the perceived 
loudness (VU) is displayed on a bar graph, and the Peak signal on a dot above the VU. With this