MultiMeter

The MultiMeter provides a collection of professional gauge and analysis tools in a single window. It includes:

You can view either the Analyzer or Goniometer results in the main display area. You switch the view and set other MultiMeter parameters with the controls on the left side of the interface.

Figure. MultiMeter window, showing different interface areas.

While you can insert the MultiMeter directly into any channel strip, it is more commonly used in the master channel strip of the host application—when you are working on the overall mix.

There is also a surround version of the MultiMeter, with parameters for each channel and a slightly different layout. See Surround MultiMeter.

Using the MultiMeter Analyzer

In Analyzer mode, the MultiMeter’s main display shows the frequency spectrum of the input signal as 31 independent frequency bands. Each frequency band represents one-third of an octave. The Analyzer parameters are used to activate Analyzer mode, and to customize the way that the incoming signal is shown in the main display.

Figure. Analyzer parameters.
  • Analyzer button: Switches the main display to Analyzer mode.
  • Left, Right, LRmax, and Mono buttons: Determine which channels are displayed in the Analyzer results, in the main display.
    • Left or Right: Displays the left or right channels.
    • LRmax: Displays the maximum level of the stereo inputs.
    • Mono: Displays the spectrum of the mono sum of both (stereo) inputs.
  • View fields: Alter the way that values are shown in the Analyzer by setting the maximum level displayed (Top) and the overall dynamic range (Range).
  • Mode buttons: Determine how levels are displayed. You can choose from Peak, Slow RMS, or Fast RMS characteristics.

    • The two RMS modes show the effective signal average, and provide a representative overview of perceived volume levels.

    • The Peak mode shows level peaks accurately.

  • Scale (shown in main display): Indicates the scale of levels. Adjusting the scale is useful when analyzing highly compressed material, as it makes it easier to identify small level differences. Drag vertically on the scale to adjust.

Using the MultiMeter Goniometer

A goniometer helps you to judge the coherence of the stereo image and determine phase differences between the left and right channels. Phase problems are easily spotted as trace cancellations along the center line (M—mid/mono).

The idea of the goniometer was born with the advent of early two-channel oscilloscopes. To use such devices as goniometers, users would connect the left and the right stereo channels to the X and Y inputs, while rotating the display by 45° to produce a useful visualization of the signal’s stereo phase.

The signal trace slowly fades to black, imitating the retro glow of the tubes found in older goniometers, while also enhancing the readability of the display.

Figure. Goniometer parameters.
  • Goniometer button: Switches the main display to Goniometer mode.
  • Auto Gain field: Sets the amount of display compensation for low input levels. You can set Auto Gain levels in 10% increments, or set it to off.

    Note: To avoid confusion with the Auto Gain parameter found in other effects and processors (such as the compressors), Auto Gain is only used as a display parameter in the meters. It increases display levels to enhance readability. It does not change the actual audio levels.

  • Decay field: Determines the time it takes for the Goniometer trace to fade to black.

Using the MultiMeter’s Level Meter

The Level Meter displays the current signal level on a logarithmic decibel scale. The signal level for each channel is represented by a blue bar.

Figure. Level Meter.

RMS and Peak levels are shown simultaneously, with RMS levels appearing as dark blue bars and Peak levels appearing as light blue bars. When the level exceeds 0 dB, the portion of the bar above the 0 dB mark turns red.

Current peak values are displayed numerically (in dB increments) above the Level Meter. Click in the display to reset peak values.

Using the MultiMeter’s Correlation Meter

The Correlation Meter gauges the phase relationship of a stereo signal. The Correlation Meter’s scale values indicate the following:

Figure. Correlation meter

  • A +1 correlation value indicates that the left and right channels correlate 100%. In other words, the left and right signals are in phase and are the same shape.

  • Correlation values in the blue zone (between +1 and the middle position) indicate that the stereo signal is mono compatible.

  • The middle position indicates the highest allowable amount of left/right divergence, which is often audible as an extremely wide stereo effect.

  • When the Correlation Meter moves into the red area to the left of the center position, out-of-phase material is present. This will lead to phase cancellations if the stereo signal is combined into a mono signal.

Using the MultiMeter Peak Parameters

The MultiMeter Peak parameters are used to enable/disable the peak hold function and to reset the peak segments of all meter types. You can also determine a temporary peak hold duration.

Figure. Peak parameters.
  • Hold button: Activates peak hold for all metering tools in the MultiMeter, as follows:
    • Analyzer: A small yellow segment above each 1/3 octave level bar indicates the most recent peak level.
    • Goniometer: All illuminated pixels are held during a peak hold.
    • Correlation Meter: The horizontal area around the white correlation indicator denotes phase correlation deviations in real time, in both directions. A vertical red line to the left of the correlation indicator shows the maximum negative phase deviation value. You can reset this line by clicking on it during playback.
    • Level Meter: A small yellow segment above each stereo level bar indicates the most recent peak level.
  • Hold Time pop-up menu: When peak hold is active, sets the hold time for all metering tools to 2, 4, or 6 seconds—or infinite.
  • Reset button: Click to reset the peak hold segments of all metering tools.
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