Table of Contents

Wwise RoomVerb

(See the Wwise RoomVerb Properties below.)

To simulate sound reflections in an acoustic space in game, you can use the Wwise RoomVerb plug-in. This plug-in effect is a versatile reverb with many controls allowing you to re-create any type of space. This reverb plug-in uses more CPU than the highly optimized Matrix Reverb, but with the additional controls available, you can achieve more realistic results.

Many of the Wwise RoomVerb properties can be edited in real time and can be mapped to specific Game Parameters using RTPCs. Property changes made via RTPCs are applied instantaneously and are properly interpolated, which means that no audio artifacts are introduced. The properties that can't be mapped to Game Parameters can still be changed on-the-fly during playback in Wwise. In some cases, however, changing these properties will result in artifacts as some parts of the Effect are effectively reset.

The Wwise RoomVerb plug-in considers the following concepts in its algorithm:

  • Modal (or frequency) density - Modes are the peaks in the frequency domain representation of an audio signal. Increasing the modal density improves the realism of the reverberation when simulating most acoustic spaces. Decreased modal density can cause ringing sounds.

  • Echo density - The amount of echoes per second produced by the reverberation algorithm. When this figure is too low, a shrilling sound is perceived. When this figure is too high, a very “dense” sounding reverb tail is heard.

RoomVerb Processing Pipeline

When the RoomVerb effect plug-in is applied to a sound, the audio signal is split into the following two parts:

  • Dry signal - The direct signal or unprocessed portion of the signal.

  • Wet signal - The processed signal or portion of the signal to which the RoomVerb effect settings are applied.

The wet portion of the RoomVerb signal consists of two main parts. The first part of the signal contains the early reflections (ER) component and the second part contains the reverb component. The ER component is optional giving you the flexibility to optimize the Effect processing and memory allocations. The various settings within the Effect plug-in define the actual ER and reverb units that are remixed with the original dry signal to create one output signal. The following illustration demonstrates the processing pipeline of a sound to which the RoomVerb effect has been applied.

Wwise RoomVerb 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.

Default value: false

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

Early Reflections

Enable Early Reflections

Specifies whether the early reflections component of the signal will be computed and processed.

Default value: true

ER pattern

A pattern containing pre-determined early reflection arrival times (in ms) and gains (linear) that are characteristic of a particular acoustical space.

ER Room Size

Determines the time scaling applied to the ER pattern.

A value of zero means there is no time scaling of the ER pattern selected, a value of 100 yields a doubling of the time taken before receiving each early reflection, and a value of -100 halves the time taken by the ER pattern chosen. Note that the time of the first early reflection is a good perceptual cue of the size of the acoustical space modeled.

Default value: 0
Range: -100 to 100

ER Rear Delay

Time delay between the early reflections fed to the front and rear channels.

When using non-zero rear delay values with surround signals in conjunction with matrix encoding systems, such as Dolby Pro Logic 2, some artifacts may be heard (usually as comb filtering). This may occur on the Xbox 360 platform while listening to the analog stereo output, for example.

Default value: 0
Range: 0 to 100
Units: ms

Reverb

Pre Delay

Specifies the time between the direct sound and the start of the dense reverb tail.

Default value: 25
Range: 0 to 1000
Units: ms

Decay Time

The time it takes for the low frequencies of the sound to fall by 60 dB from its original amplitude.

Default value: 1.2
Range: 0.2 to 10
Units: s

HF Damping

A roll-off factor used to control the reverberation time for high frequencies relative to low frequencies.

When the value of this ratio is less than 1, the high frequency reverberation time becomes longer than that for lower frequencies.

Default value: 2.25
Range: 0.5 to 10

Density

Directly modifies the perceived modal density. Lower values often result in a certain amount of ringing while higher settings sound flatter in frequency with a noisy reverb tail.

This property is directly proportional to the amount of memory used by the plug-in because higher modal density is achieved using longer delay lines. These longer delay lines are analogous to larger spaces so this property can sometimes be used to control the perceived room size. This property works closely with the ‘Room shape’ and ‘Quality’ properties.

Default value: 80
Range: 0 to 100
Units: %

Room Shape

Determines the perceived coloration of the reverb by controlling (along with the Density property) the delay lengths used by the algorithm while maintaining a constant modal density. In general, a high room shape setting will mean less divergence between the longest and shortest delay lengths. This could be analogous to a regularly shaped room, a cube for instance. At lower room shape settings, the divergence between delay lines is larger.

It is recommended that you experiment with different Room shape settings for each Density value.

Default value: 100
Range: 0 to 100
Units: %

Quality

Determines the number of reverberation units used by the algorithm. A higher Quality value can help change the audio quality of the reverberation significantly but will result in a proportional increase in CPU usage.

If you increase Quality, you may want to reduce the Density and the reverse is also true. Lower Quality values, such as 2, often do not provide the necessary echo density for realistic reverberation. Higher Quality values may produce the effect of more reflective rooms.

Default value: 8
Range: 2 to 16
Units: Reverberations

Diffusion

Directly controls the echo density characteristic of the reverb. A lower Diffusion value will sometimes result in a shrilling sound where each echo can be distinctively perceived. Higher Diffusion values give a denser reverberation tail. Higher diffusion also means that transient signals are blurred in time with their energy spread over some interval of time. the effect of this property will be noticeable mostly on materials with sharp transients, for example, snare drum hits.

Default value: 100
Range: 0 to 100
Units: %

Stereo Width

Determines the similarity between the ER + reverb content that is output in the left channels (front and/or rear) and right channels (front and/or rear). This can create a stronger sense of space, by enlarging the stereo spread of the early reflections and the reverberation.

When a value of zero is used, the ER + reverb output to the left and right channels is the same. As a result, some memory and CPU optimization can be obtained. A value of 180 means that an entirely different ER + reverb signal is fed to each side. This effect is stronger when monitored over headphones due to the absence of cross-talk between speaker signals which diminishes the Effect.

This property has no effect on 1.0 (mono) or 1.1 channel sounds.

Default value: 180
Range: 0 to 180
Units: °

Tone

Enable Tone

Specifies whether shelving and peaking filters can be applied to the various components of the reverberated signal. When selected, you can apply up to three different filters. Each filter can also be inserted at various points in the signal chain.

Default value: false

Filter Band Insert

Determines the point in the signal chain at which filters are applied. The following insertion points are available:

  • Off: No filter is applied.
  • ER only: Applies the filter to the early reflection portion of the signal.
  • Reverb only: Applies the filter to the reverb tail portion of the signal.
  • ER + Reverb: Applies the filter to both the early reflection and reverb tail portions of the signal.

When the Early reflections option is not selected, the ER component will always be ignored no matter which insertion point is selected.

Default value: ER + Reverb

Filter Band Curve

Determines the type of filtering that can be applied to the signal. The following filters are available:

  • Low shelf - Boosts or cuts the lower-level frequencies while leaving high frequencies unaffected.
  • Peaking - Boosts or cuts a specific frequency region while leaving lower and higher frequencies unaffected. The width of this frequency region can be controlled using the Q property.
  • High shelf - Boosts or cuts the higher-level frequencies while leaving low frequencies unaffected.

Default value: High shelf

Gain

The amount by which the audio signal is amplified for the selected frequency band. Increasing this value boosts the audio signal. Decreasing this value cuts or attenuates the audio signal.

Default value: 0
Range: -32 to 32
Units: dB

Filter Band Frequency

The portion of the frequency spectrum that will be affected by the gain.

Default value: 10000
Range: 20 to 20000
Units: Hz

Filter Band Q

The area around the center frequency that will be affected by the change in gain. A low Q value means that the bandwidth range will be wide and, conversely, a high Q value means that the bandwidth range will be narrow.

The Q property is only available when the Curve property is set to Peaking.

Default value: 1
Range: 0.1 to 10

Input Levels

Center Input Level

Determines the amount of the Center channel that will contribute to feed the reverberation algorithm.

Default value: 0
Range: -96.3 to 0
Units: dB

LFE Input Level

Determines the amount of the LFE channel that will contribute to feed the reverberation algorithm.

Default value: -96.3
Range: -96.3 to 0
Units: dB

Reverb Levels

Front Level

Controls the amount of late reverberation applied to the front left and right channels. This property control does not affect the center channel, which can be controlled explicitly.

This property has no effect in channel configurations where rear channels are not present. In these cases, controlling the wet level (ER + Reverb) is more intuitive.

Default value: 0
Range: -96.3 to 0
Units: dB

Rear Level

Controls the amount of late reverberation applied to the rear left and right channels.

This property has no effect in channel configurations where rear channels are not present. In these cases, controlling the wet level (ER + Reverb) is more intuitive.

Default value: 0
Range: -96.3 to 0
Units: dB

Center Level

Controls the amount of late reverberation applied to the center channel, when present.

Default value: 0
Range: -96.3 to 0
Units: dB

LFE Level

Controls the amount of late reverberation applied to the LFE channel, when present.

Default value: -96.3
Range: -96.3 to 0
Units: dB

Output Levels

Dry Level

Determines the gain factor that is applied to the direct path sound.

[Note] Note

This property has no effect when the reverb is used in an Auxiliary Bus. In this case, the dry signal is defined by the object sending to the Auxiliary Bus.

Default value: -96.3
Range: -96.3 to 0
Units: dB

ER Level

Determines the gain factor that is applied to the early reflection signal.

This control has no effect when the Early reflections check box is not selected.

Default value: -20
Range: -96.3 to 0
Units: dB

Reverb Level

Determines the gain factor that is applied to the reverberated signal (reverb tail).

Default value: -20
Range: -96.3 to 0
Units: dB

 

Estimated memory usage

The estimated amount of memory, in KB, used to generate the Effect. This estimate assumes a surround configuration. If the rear left and rear right channels are not present, the memory used will be slightly lower than the amount displayed.

For the Windows platform, this value assumes that the sound quality (AkSoundQuality) is set to High (48 kHz sampling rate). If the sound quality is set to Low (24 kHz sample rate), then the estimated amount of memory will typically be half of the value displayed.