Table of Contents

Wwise Flanger

(See the Wwise Flanger Properties below.)

Flanging is an audio effect that occurs when two identical signals are mixed together, but with one signal time-delayed by a small and gradually changing amount. This produces a swept comb filter effect: peaks and notches are produced in the resultant frequency spectrum, related to each other in a linear harmonic series. Varying the time delay with an LFO oscillator causes these to sweep up and down the frequency spectrum.

Comb Filter Spectral Controls

The Wwise flanger algorithm is based on a 'unified comb filter' that allows for controlling the depth of notches and peaks as well as their relative location (for example, on odd or even harmonics). This allows the comb filter to provide a wide variety of spectrum shaping by directly modifying the 'feedforward' and 'feedback' coefficients.

The following figures exemplify the type of magnitude response that can be achieved using a fixed delay time of 0.5 ms. The feedforward coefficient controls the depth of notches in the spectrum, while the feedback coefficient controls the magnitude of peaks.

The sign of the coefficient can control whether the notches or peaks occur on odd harmonics (for positive coefficients) or even harmonics (for negative coefficients) as shown below.

The feedfoward and feedback components can be used together to build different spectral shapes for combining the effect of notches and peak as shown below.

The delay time effectively controls the spacing between notches and/or peaks. By doubling the delay time, the distance between notches is halved as shown in the example below.

Alternate Effects

With the additional flexibility provided by the 'Blend' parameter which allows to mix the input to the delay line (including the feedback path) with the feedforward path of the delay line, effects other than flanging may be achieved.

One example of this is the vibrato effect (a regular pulsating change of pitch). Vibrato can be characterized by the amount of pitch variation and speed with which the pitch is varied. By setting both the feedback and blend values to 0, only the (modulated) feedforward path is preserved (vibrato component).

Wwise Flanger Properties

The Wwise Flanger 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.

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

Delay

The delay parameter used by the comb filter. Small delay values result in few spectral notches/peaks. Large delay values result in smaller spacing between frequency notches/peaks.

Default Value: 5
Range: 0.2 to 10
Units: milliSeconds

Color Settings

Blend

Scaling factor for signal not entering the modulated delay line (sum of feedback and dry signal). Can be used to create a large range of effect from flanging to vibrato.

Default Value: 1
Range: 0 to 1
Units: Linear gain

Feedforward

Scaling factor for the contribution of the feedforward path out of the modulated comb filter. Large (absolute) values of this parameter results in stronger notches in the spectrum. Negative values places notches at even harmonic locations instead.

Default Value: 1
Range: -1 to 1
Units: Linear gain

Feedback

Scaling factor for the contribution of the feedback path out of the modulated comb filter. Large (absolute) values of this parameter result in stronger peaks in the spectrum. Negative values place peaks at even harmonic locations instead.

Default Value: 0
Range: -1 to 1
Units: Linear gain

Output Settings

Wet/Dry Mix

Controls the balance between the wet path (the output of the Effect) and the dry path (the input of the Effect). A value of 0 yields the original signal unaffected by the Effect while the a value of 100 outputs only the output of the Effect.

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

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 Center

Determines whether the Effect is processing the center channel or not. When unselected, the center channel is unaffected by the Effect.

Default: Off

Process LFE

Determines whether the Effect is processing the LFE channel or not. When unselected, the LFE channel is unaffected by the Effect.

Default: Off

LFO Section

Depth

Amount of amplitude modulation that controls the actual delay length, in percentage. At 0%, the delay length used by the comb filter is always as specified by the delay parameter. At 100%, the delay length is modulated to its full range.

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

Frequency

Frequency of the modulating signal.

Default Value: 1
Range: 0 to 20
Units: Hz

Waveform

Shape of the modulating signal.

Values: Sine, Square, Triangle, Upward sawtooth, Downward sawtooth.

[Warning] Warning

Although this parameter can be changed at run-time using RTPCs, the signal is not guaranteed to be continuous.

Smoothing

Amount of smoothing applied to the modulating signal. It is low-pass filtered by a certain value, mapped from 0 to 100%. At 0%, the signal comes out intact. With higher values, edges and discontinuities are smoothed.

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

[Note] Note

This setting has no effect on the sine waveform.

PWM (Pulse Width Modulation)

Applies to the square waveform only. Modulates the width of the pulse during one cycle. At 50%, the signal is at its full amplitude for half of the cycle, and is 0 for the other half. Near 100%, the signal is at its full amplitude for almost all the cycle, while it drops to 0 for a very short amount of time.

Default Value: 50
Range: 0 to 50
Units: %

Initial Phase Section

Offset

Offsets phase of the modulating signal of all channels by a specific value.

Default Value: 0
Range: -180 to 180
Units: Degrees

[Note] Note

Although this parameter can be changed at run-time via RTPC, it has no effect when it is set after the instance of this effect has started playing.

Spread Mode

Defines how initial phase spread (see parameter "Spread") is applied across channels. For example, with the spread mode set to "Front-Rear", all front channels start playing with a phase equal to 0, and all rear channels start playing with a phase equal to "Spread". If present (and processed), the LFE channel is always synchronized with the Front Left channel.

Values:

  • Left-Right: Front and rear left channels start with an offset of 0, front and rear right channels start with an offset of "Spread". If present, the center channel starts with an offset of "Spread"/2.

  • Front-Rear: Front and center channels start with an offset of 0, and rear channels start with an offset of "Spread".

  • Circular: This mode applies a spreading dipole between the left and right channels on 1.x, 2.x and 3.x configurations, and between the front left and rear right channel on 4.x and 5.x configurations. For example, a 3.0 signal would start with the following phases: L=0, C="Spread"/2, R="Spread". A 5.0 signal would start with the following phases: FL=0, C="Spread"/4, FR="Spread"/2, RL="Spread"/2, RR="Spread".

  • Random: Each channel starts with a random phase uniformly distributed between 0 and "Spread".

[Note] Note

Although this parameter can be changed at run-time via RTPC, it has no effect when it is set after the instance of this effect has started playing.

Spread

Amount of divergence in the initial phase spread across channels. The way in which this value affects each channel depends on the spread mode.

Default Value: 0
Range: 0 to 180
Units: Degrees

[Note] Note

Although this parameter can be changed at run-time via RTPC, it has no effect when it is set after the instance of this effect has started playing.

[Caution] Caution

Keep in mind that the Feedback parameter can make the sound grow increasingly for large parameter values.

[Caution] Caution

The effect tail (that is, the time after the input sound is finished during which the Effect continues to output data that it has accumulated in its delay line) does not consider feedback. This means that for strong feedback value the Effect could terminate with a significant volume still processed.

See also Wwise Tremolo Properties for more detailed explanations on LFO parameters.