Larson Davis System 824, Справочное руководство

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11/8/00 RTA (optional) 10-15
RTA Settings
RT60 dB Down
The automatic RT60 algorithm will search for a point 5 or
more dB down from the maximum sample and then calcu-
late an RT60 between that point and the next point, “RT60
dB Down”.
Example: If “RT60 dB Down” is set
to 30 dB, the RT60 will be calculated
for the data between 5 and 35 dB
down from the max. • 5 dB
• 10 dB
• 15 dB
• 20 dB
• 25 dB
• 30 dB
Auto RT60
The Auto RT60 setting, when enabled, automatically calcu-
lates the RT60 for each filter, on screen, as the user moves
between filters using the up
u
and down
d
arrow keys.
Note
If Note ends with a numeral it will be
incremented automatically with each
spatial average snapshot taken or
stored. An 8 character note field is provided to annotate a spatial
average. This is useful when describing the measurement
you are taking and keeping track of different measurements
or their location.
RT60-A and RT60-B Instrument Definition
The System 824 contains two special RTA IDs on the setup
menu which will simplify making an RT60 measurement.
Both of these setups load the RTA instrument but with the
triggering, arm, and end menus configured for two types of
measurements.