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PAM1 MK2
User Handbook Issue 1
2.16
Loudness Measurement
ITU-R BS1770
Loudness Setup
menu is accessed from the
Main Menu
.
PAM1
aims to provide the user with a set of tools which comply with the recommendations of both
the
ATSC (A85)
and
EBU (R128)
Loudness committees whilst giving the flexibility to tailor
operation to suit local requirements.
The
Loudness Setup
menu may be used to define the parameters used to measure
Loudness
using the
ITU-R BS1770
algorithm, to select and set the specific audio channels under test and to
start/stop measurement manually. The resultant
Loudness
measurement may be observed via
either the
Bargraph Display
or from the
Loudness Histogram
which is accessed via the
Data
button.
The
Loudness
implementation does not require the operator to listen to the audio components
being measured as the location of the
Hear Box
and
Loudness Cursor
may be independent of
one another
(Fixed
and
Dolby
source modes).
2.16.1
Source Selection.
The
PAM1
comprises 4 modes of operation for use when measuring Loudness from a User
determined audio signal. In
Fixed mode
the user is able select whichever channels are subject to
measurement,
Follow mode
takes a measurement of a 5.0 signal determined by the location of
the yellow
‘Hear’
box and finally
Dolby mode
automatically selects the surround sound
components of a decoded
Dolby E, Digital or Digital Plus
signal.
Off Mode:
The
Loudness
menu
Source Selection
includes an
OFF
position for use when the
Loudness
measurement is not required. This switch position disables all onscreen representation
of
Loudness
measurement including the
Target
value,
Measured
value,
Histogram
and
Menu
selection
