Table of Contents

Wwise Compressor

(See the Wwise Compressor Properties below.)

The Wwise Compressor plug-in reduces the dynamic range of a signal by weakening any part of the input signal that is above a pre-defined threshold value. When the signal is loud and above the threshold, the Compressor begins to reduce the signal's gain. When the signal is softer or lower than the threshold value, no gain reduction is applied to the signal.

A ratio factor determines the extent of the dynamic compression when the input is above the threshold. For example, a ratio of 4 means that for every 4 dB the input signal is over the threshold, only 1 dB will be observed in the output signal.

To provide smooth transitions between the areas of gain reduction and no gain reduction, you can specify times for the attack and release properties. The attack time is the time it takes for the gain to be reduced. The release time is the time it takes for the signal to return to normal levels, where gain reduction is no longer applied.

The Wwise Compression plug-in contains a series of properties, many of which can be edited in real-time and can be mapped to specific Game Parameters using RTPCs.

You can use the Compressor plug-in to create a variety of different effects. For example, you could simulate radio communication between game characters by routing a white noise sound and different voice sounds to the same bus and then applying a Compressor effect on the bus. The compressor properties can be set so that the white noise will increase between gaps in words or phrases and decrease as soon as a voice is heard.

[Caution] Caution

Sounds with a DC offset may alter the results of the compression effect. Make sure to remove the DC offset before applying the Compression effect in Wwise.


[Note] General remarks on Wwise dynamic processing plug-ins
  • There is no interpolation of ratio control (RTPC parameter) for Wwise Compressor, Wwise Expander, or Wwise Peak Limiter. Changing this parameter during playback may lead to signal discontinuities on very clean signals.

  • Sounds with DC offset may alter results of compression/expansion because the sidechain detection algorithm will be offset considerably. DC offset should be removed prior to use in Wwise.

  • The Compressor, Expander, and Peak limiter are non-linear audio processes. This means that order of processing is important. For example, results will be different if you apply gain before or after the Effect.

  • For the first audio buffers, the processing algorithms are said to be in non-steady state. Because the estimated signal power operated by the side chain has no knowledge of the past, its estimate of signal power may be erroneous for a short period of time (but only if the Compressor is already engaged at the start of the sound). A solution to this (if it's a problem at all) is to start the Compressor with a ratio of 1 and shortly after bring it to the desired value.

  • If the Compressor applies some gain reduction and is suddenly bypassed, a signal discontinuity will be heard. A potential solution is to gradually bring the ratio to 1 prior to bypassing the Effect.

Wwise Compressor Properties

Interface Element

Description

Inclusion

Determines whether the element is included or excluded. When selected, the element is included. When unselected, the element is not included. By default, this applies across all platforms. Use the Link indicator (to the left of the check box) to determine or to set platform-specific customizations.

When this option is unselected, the property and behavior options in the Property Editor become unavailable.

Name

The name of the Effect instance.

Effect instances are a group of effect property settings. They can be one of two types: custom instances or ShareSets. Custom instances can be used by only one object, whereas ShareSets can be shared across several objects.

Effect

The type of effect.

Shared by (Used by)

A list of objects that currently subscribe to the selected ShareSet.

This field is called “Used by” when editing a custom instance of the Effect.

Opens a search field where standard alphanumeric entries filter out unmatching elements from the view. Learn more in Using Tables.

Click the Close icon to the left of the search icon to close the search field and remove the filter.

[Note] Note

The searches do not include elements in collapsed nodes of the List View, Query Editor, MIDI Keymap Editor, and Reference View.

Returns the Effect property settings to their default values.

This option is only available when editing a custom instance of the Effect.

Notes

Additional information about the Effect.

Effect Settings

Threshold

The level of the input signal above which the compressor will begin to apply gain reduction.

Default Value: -12
Range: 0 to -96.3
Units: dB

Ratio

The relationship between the input signal and the output signal above a threshold value. This value defines the slope of the output signal above the threshold.

A ratio of 2:1 indicates that for every 2 dB the input signal is above the threshold, only 1 dB will be observed in the output signal. At a ratio of 10:1 and higher, limiting occurs.

Default Value: 4
Range: 1 to 50

Attack

The amount of time it takes the Compressor to apply the gain reduction as the input level rises above the threshold.

Default Value: 0.01
Range: 0.0 to 0.5
Units: Seconds

[Note] Note

If the Attack time is set to 0, then there is no output.

Release

The amount of time it takes the Compressor to remove the gain reduction as the input level falls below the threshold.

Default Value: 0.1
Range: 0.001 to 0.5
Units: Seconds

Output gain

The amount of gain applied to the output signal after the dynamic compression that makes up for potential gain losses.

Default Value: 0
Range: -24 to 24
Units: dB

Process LFE

Determines whether the Effect is processed in the LFE channel or not. When selected, the Effect is processed in the LFE channel. When unselected, the LFE channel will be unaffected.

Channel link

Applies the same gain reduction to all channels. This is implemented by taking the RMS power in the signal of all channels. The threshold is set by scaling the power in dB for the number of channels that are linked.

If this option is not selected, no information is shared between channels, and the Effect is applied on a per-channel basis.