Tektronix WFM5200 & WVR5200, Инструкция по эксплуатации

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How to Guide Audio Loudness Monitoring
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Function Description
Loudness Ballistic
The user can select a variety of Ballistics for the Loudness Meter

Short Average - Applies a variable time duration to the integration
window of the loudness measurement. The Average Integration Time
defines the duration of the integration window and is configured
within the Loudness Settings menu. The value can range from one to
60 seconds with a default value of 10 seconds.

Long Average - Integrates the loudness measurement continuously
over the audio session duration. The audio session can be started,
stopped or reset by the user. If gating is applied then some
measurement results may be excluded from the loudness
measurements.

Ungated Long - Integrates the loudness measurement continuously
over the audio session duration. The audio session can be started,
stopped or reset by the user. This Loudness ballistic does not apply
gating to the overall measurement.

IEC 62672F - This time-weighted function applies to the audio level
meters and affects how quickly the bars rise when the signal level
increases and fall when the signal level decreases. Loudness F has a
0.125 second time constant.

IEC62672S - This time-weighted function applies to the audio level
meters and affects how slowly the bars rise when the signal level
increases and fall when the signal level decreases. Loudness S has a
1 second time constant.

EBU R/128M - This measurement applies the M (Momentary)
ballistic per EBU R/128 with a 400ms integration time.
Channel Weighting
Custom Mask
The Channel Weighting allows you to select a number of channels (L,
R, C, Lfe, Ls, Rs, Lb, Rb, S, M, Le, Re) that are used in the Program
Loudness calculation in the Audio Session screen and Loudness meter.
There are several selections available:
Custom Selects the channel based on the Custom Mask selected by the
user.

All Channel Selects All Channels to be included in Channel
Weighting.

Exclude LFE Select All Channels except the LFE (Low Frequency
Effects Channel).

ITU-R BS.1770 Applies ITU-R BS.1770 weighting of +1.5dB to the
surround channels and includes all channels except LFE.
Note: In the Audio Display a Green label for the audio bar indicates that
it is included in the Channel Weighting.
The Audio Session and the Loudness Session display provide status
information of the channels included in the Channel Weighting.
The
Custom Mask menu selection allows the user to customize the
included channels when Custom is selected for Channel Weighting.