Cobalt Digital COMPASS 9086 Embedded Audio Loudness Processor - Manual (Page 73)

9086-OM (V4.3) 9086-SD PRODUCT MANUAL A-5
Appendix A
Measurement Techniques For Various Program Material Forms
Figure A-2 LKFS Measurement/Assessment for Various Program Material Forms
Material Run
Duration (58 sec.)
Dialnorm
HI Limit
LO Limit
0
-10
-30
-40
Relatively high density and compression results in fairly
consistent short-term LKFS, leading to an LKFS
measurement that is highly representative of the entire
piece.
Material Run
Duration (5 min.)
Dialnorm
HI Limit
LO Limit
0
-10
-30
-40
Intentionally quiet segment, if included in measurement with
no consideration of technique, leads to an LKFS measurement
that is under-representative of the entire piece.
5-minute Nature Show Act with Narrative/Background Music and Creative-Element Near Silence. In this example, predominate narrative dialog in
the center channel serves as an anchor element, with subordinate elements being music score and ambient soundtrack. However, the piece also contains
a significantly long segment containing only very low-level ambient soundtrack during a nature close-up sequence. This loudness change is creatively
intentional and must be maintained. If this segment is included in the LKFS observation, it can result in an under-representation of overall perceived
loudness. If the gain is increased to compensate for this under-represented LKFS, loudness during periods of narrative/music will be unacceptably high.
As such, proper technique would be to ignore the quiet portion.
60-second Commercial with Dialog and Background Music. In this example, predominate dialog in the center channel serves as an anchor element.
Because of the relatively compressed and dense audio content, a simple observation over the course of the material can reliably be used to apply gain
adjustment that correspondingly provides loudness correction.