XAUDIO2FX_REVERB_PARAMETERS Structure
Describes parameters for use in the reverb APO. These parameters support 7.1 surround sound.
Syntax
typedef struct XAUDIO2FX_REVERB_PARAMETERS {
float WetDryMix;
UINT32 ReflectionsDelay;
BYTE ReverbDelay;
BYTE RearDelay;
BYTE SideDelay;
BYTE PositionLeft;
BYTE PositionRight;
BYTE PositionMatrixLeft;
BYTE PositionMatrixRight;
BYTE EarlyDiffusion;
BYTE LateDiffusion;
BYTE LowEQGain;
BYTE LowEQCutoff;
BYTE HighEQGain;
BYTE HighEQCutoff;
float RoomFilterFreq;
float RoomFilterMain;
float RoomFilterHF;
float ReflectionsGain;
float ReverbGain;
float DecayTime;
float Density;
float RoomSize;
BOOL DisableLateField;
} XAUDIO2FX_REVERB_PARAMETERS;
Members
WetDryMix
Percentage of the output that will be reverb. Allowable values are from 0 to 100.
ReflectionsDelay
The delay time of the first reflection relative to the direct path. Permitted range is from 0 to 300 milliseconds.
Note
All parameters related to sampling rate or time are relative to a 48kHz sampling rate and must be scaled for use with other sampling rates. See remarks section below for additional information.
ReverbDelay
Delay of reverb relative to the first reflection. Permitted range is from 0 to 85 milliseconds.
All parameters related to sampling rate or time are relative to a 48kHz sampling rate and must be scaled for use with other sampling rates. See remarks section below for additional information.
RearDelay
Delay for the left rear output and right rear output. Permitted range is from 0 to 5 milliseconds for all output except 7.1. For 7.1 the permitted range is 0 to 20 milliseconds.
All parameters related to sampling rate or time are relative to a 48kHz sampling rate and must be scaled for use with other sampling rates. See remarks section below for additional information.
SideDelay
SideDelay is unique to Xbox One, and applies only to 7.1 surround sound.
Delay for the left side output and right side output. Permitted range is from 0 to 5 milliseconds. This parameter is still validated even when it is not used.
PositionLeft
Position of the left input within the simulated space relative to the listener. With PositionLeft set to the minimum value, the left input is placed close to the listener. In this position, early reflections are dominant, and the reverb decay is set back in the sound field and reduced in amplitude. With PositionLeft set to the maximum value, the left input is placed at a maximum distance from the listener within the simulated room. PositionLeft does not affect the reverb decay time (liveness of the room), only the apparent position of the source relative to the listener. Permitted range is from 0 to 30 (no units).
PositionRight
Same as PositionLeft, but affecting only the right input. Permitted range is from 0 to 30 (no units).
PositionRight is ignored in mono-in/mono-out mode.
PositionMatrixLeft
Gives a greater or lesser impression of distance from the source to the listener. Permitted range is from 0 to 30 (no units).
PositionMatrixRight
Gives a greater or lesser impression of distance from the source to the listener. Permitted range is from 0 to 30 (no units).
PositionMatrixRight is ignored in mono-in/mono-out mode.
EarlyDiffusion
Controls the character of the individual wall reflections. Set to minimum value to simulate a hard flat surface and to maximum value to simulate a diffuse surface. Permitted range is from 0 to 15 (no units).
LateDiffusion
Controls the character of the individual wall reverberations. Set to minimum value to simulate a hard flat surface and to maximum value to simulate a diffuse surface. Permitted range is from 0 to 15 (no units).
LowEQGain
Adjusts the decay time of low frequencies relative to the decay time at 1 kHz. The values correspond to dB of gain as follows:
| Value | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gain (dB) | -8 | -7 | -6 | -5 | -4 | -3 | -2 | -1 | 0 | +1 | +2 | +3 | +4 |
A LowEQGain value of 8 results in the decay time of low frequencies being equal to the decay time at 1 kHz.
Permitted range is from 0 to 12 (no units).
LowEQCutoff
Sets the corner frequency of the low pass filter that is controlled by the LowEQGain parameter. The values correspond to frequency in Hz as follows:
| Value | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|
| Frequency (Hz) | 50 | 100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 |
Permitted range is from 0 to 9 (no units).
HighEQGain
Adjusts the decay time of high frequencies relative to the decay time at 1 kHz. When set to zero, high frequencies decay at the same rate as 1 kHz. When set to maximum value, high frequencies decay at a much faster rate than 1 kHz.
| Value | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
|---|---|---|---|---|---|---|---|---|---|
| Gain (dB) | -8 | -7 | -6 | -5 | -4 | -3 | -2 | -1 | 0 |
Permitted range is from 0 to 8 (no units).
HighEQCutoff
Sets the corner frequency of the high pass filter that is controlled by the HighEQGain parameter. The values correspond to frequency in kHz as follows:
| Value | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frequency (kHz) | 1 | 1.5 | 2 | 2.5 | 3 | 3.5 | 4 | 4.5 | 5 | 5.5 | 6 | 6.5 | 7 | 7.5 | 8 |
Permitted range is from 0 to 14 (no units).
RoomFilterFreq
Sets the corner frequency of the low pass filter for the room effect. Permitted range is from 20 to 20,000 Hz.
All parameters related to sampling rate or time are relative to a 48kHz sampling rate and must be scaled for use with other sampling rates. See remarks section below for additional information.
RoomFilterMain
Sets the pass band intensity level of the low-pass filter for both the early reflections and the late field reverberation. Permitted range is from -100 to 0 dB.
RoomFilterHF
Sets the intensity of the low-pass filter for both the early reflections and the late field reverberation at the corner frequency (RoomFilterFreq). Permitted range is from -100 to 0 dB.
ReflectionsGain
Adjusts the intensity of the early reflections. Permitted range is from -100 to 20 dB.
ReverbGain
Adjusts the intensity of the reverberations. Permitted range is from -100 to 20 dB.
DecayTime
Reverberation decay time at 1 kHz. This is the time that a full scale input signal decays by 60 dB. Permitted range is from 0.1 to infinity seconds.
Density
Controls the modal density in the late field reverberation. For colorless spaces, Density should be set to the maximum value (100). As Density is decreased, the sound becomes hollow (comb filtered). This is an effect that can be useful if you are trying to model a silo. Permitted range as a percentage is from 0 to 100.
RoomSize
The apparent size of the acoustic space. Permitted range is from 1 to 100 feet.
DisableLateField
If set to TRUE, disables late field reflection calculations. Disabling late field reflection calculations results in a significant CPU time savings.
Remarks
All parameters related to sampling rate or time are relative to a 48kHz voice and must be scaled for use with other sampling rates. For example, setting ReflectionsDelay to 300ms gives a true 300ms delay when the reverb is hosted in a 48kHz voice, but becomes a 150ms delay when hosted in a 24kHz voice.
The following table lists constants relating to the Xbox One specific 7.1 parameters.
| Constant | Value |
|---|---|
| XAUDIO2FX_REVERB_MIN_7POINT1_SIDE_DELAY | 0 |
| XAUDIO2FX_REVERB_MIN_7POINT1_REAR_DELAY | 0 |
| XAUDIO2FX_REVERB_MAX_7POINT1_SIDE_DELAY | 5 |
| XAUDIO2FX_REVERB_MAX_7POINT1_REAR_DELAY | 20 |
| XAUDIO2FX_REVERB_DEFAULT_7POINT1_SIDE_DELAY | 5 |
| XAUDIO2FX_REVERB_DEFAULT_7POINT1_REAR_DELAY | 20 |
Also refer to the inline helper method ReverbConvertI3DL2ToNative.
Requirements
Header: Declared in xaudio2fx.h.
Library: Use xaudio2.lib.