TC Electronic SYSTEM 6000 MKII Algorithm Manual

110
lM6
Introduction
Since1998,TChasperformedlisteningtestsandevaluationofloudnessmodels;andthereforeholdsanextensive,
UniversalDatabaseofloudness,basedontenthousandsofassessments.Thedatabasecoversallsortsofbroadcast
material, music, commercials, feature film and experimental sounds, and is verfied against other independent studies.
Fig 1.
Left: DRT for consumers under different listening situations
Right: Peak level normalization means that material targeted low dynamic range platforms gets loud.
TheUniversalDatabaseisauthoritativefroman
academic as well as a practical point of view. It has been
indispensable when designing the LM6 meter, because it
providedthemissinglinkbetweenshort-termandlong-term
loudness,andenabledthestatisticallyfoundedUniversal
Descriptors of LM6 .
ThechartofDynamicRangeToleranceinFig1isa
side-effect of the studies mentioned: Consumers were
found to have a distinct Dynamic Range Tolerance (DRT)
specific to their listening environment. The DRT is defined
asaPreferredAveragewindowwithacertainpeaklevel
Headroom above it. The average sound pressure level,
which obviously is different from one listening condition to
another,hastobekeptwithincertainboundariesinorder
to maintain speech intelligibility, and to avoid music or
effects from getting annoyingly loud or soft.
Audio engineers instinctively target a certain DRT profile
when mixing, but because level normalization in broadcast
andmusicproductionisbasedonpeaklevelmeasures,
low dynamic range signatures end up the loudest as shown
bytheredlineinFig1,right.Audioproductionistherefore
trapped in a downwards spiral, going for ever decreasing
dynamicrange.Bynow,thepopmusicindustryis“rightof”
InFlightEntertainmentintheillustration.
LM6 offers a standardized option: The visualization of
loudness history and DRT in combination with long-term
descriptors from production onwards, is a transparent
andwellsoundingalternativetoourcurrentpeaklevel
obsession. Not only for music, but also in production for
broadcast or film. The engineer, who may not be an audio
expert,shouldbeabletoidentifyandconsciouslywork
with loudness developments within the limits of a target
distribution platform, and with predictable results when the
program is transcoded to another platform.
LM6thereforecolorcodesloudnesssoit’seasytoidentify
target level (green), below the noisefloor level (blue), or
loudevents(yellow),seeFig2.

TC Electronic SYSTEM 6000 MKII Specifications

General

Brand	TC Electronic
Model	SYSTEM 6000 MKII
Category	Computer Hardware
Language	English