Sony Pro 10, Руководство пользователя

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Choosing a VU or PPM scale
To change the scale of the meter, choose Channel Meters from the Options menu, choose VU/PPM Scale , and then choose a setting
from the submenu (you can also right-click the meter to set its options).
VU and PPM scales are most useful for displaying the average volume of the signal. The meter represents the RMS average level during
playback, and their attack and decay are not as sensitive as the peak meter.
PPM scales are useful for monitoring peak levels. The meters use a fixed integration time (5 or 10 ms) that is sensitive to increases in
volume, but the meters are less sensitive to decreases in volume than the VU scales, which produces less meter activity and decreased
eyestrain.
Item Description
Traditional VU The traditional VU meter is displayed with a scale of –10 dB to +2 dB. 0 dB on the VU meter equals 4 dBu.
Extended VU The extended VU meter is displayed with a scale of –30 dB to +8 dB. 0 dB on the VU meter equals 4 dBu.
Logarithmic VU Displays the meters in a logarithmic scale (like the Sound Forge peak meters) instead of the linear scales traditionally
associated with VU meters.
UK PPM The UK peak program meter (also known as a BBC meter) is a Type II meter and is displayed with a scale of 1 to 7,
which corresponds to a range of -12 to 12 dBu:
UK Marks dBu
7 12
6 8
5 4
4 0
3 4
2 8
1 -12
EBU PPM The EBU peak program meter is a Type II meter and is displayed with a scale of –12 to +12, which corresponds to -12
dBu to 12 dBu. 0 on the EBU PPM equals 0 dBu.
The EBU PPM and UK PPM respond identically to increases in volume, but the EBU PPM decays more slowly.
DIN PPM The DIN peak program meter is a Type I meter and is displayed with a scale of –50 dB to +5 dB, which corresponds to ­
44 dBu to 11 dBu. 0 dB on the DIN PPM equals 6 dBu.
Nordic PPM The Nordic peak program meter is a Type I meter and is displayed with a scale of –42 dB to +12 dB, which corresponds
to -42 dBu to 12 dBu. 0 dB on the Nordic PPM equals 0 dBu.
Adjusting the VU/PPM meters’ sensitivity
Unlike peak meters, which read instantaneous changes in your audio signal, the VU/PPM meters read a portion of the signal and
calculate the average level. The size of the signal that the meters read is determined by the meters’ integration time.
To set the amount of data surrounding the cursor that will be used to calculate levels in the VU meters, specify a value in the VU meter
integration time box on the
Status tab of the Preferences dialog.
The PPM scales use a fixed integration time:
Scale Integration time
UK PPM 10 ms
EBU PPM 10 ms
DIN PPM 5 ms
Nordic PPM 5 ms
LEARNING THE SOUND FORGE PRO WORKSPACE |
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