Monitoring with VU and peak program meters

You can display volume unit (VU) and peak program (PPM) meters in the Channel Meters to help you determine the perceived loudness of your audio signal (peak program meters provide faster response times to volume increases than VU meters).

VU/PPM meters are especially helpful when you're mastering: comparing two audio files' VU/PPM readings will help take the guesswork out of matching levels.

Control-click the Channel Meters and choose Show VU/PPM from the shortcut menu to toggle the display of the VU/PPM meters. VU/PPM readings should fall near the 0 (or reference) mark. 0 VU is merely a reference level, and your signal may exceed 0 VU. To prevent clipping, keep an eye on your peak meters. Peak levels should never exceed 0 dB. For more information, see "Monitoring peak levels."


Showing or hiding VU/PPM meters

If the Meters tool is not visible, you can select the Show or hide the right pane button or choose View > Meters. For more information, see "Arranging editing views."

Click the arrow to show or hide the meters.

Control-click the Channel Meters and choose Show VU/PPM from the shortcut menu to show or hide VU/PPM meters.

Choosing a VU or PPM scale

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.

To change the scale of the meter, perform the following steps:

  1. Choose OptionsChannel MetersVU/PPM Scale (or Control-click the Channel Meters and choose VU/PPM Scale).

  2. Choose a setting from the submenu:

    Setting

    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.