SMixer2x1

Overview

2-input x 1-output smoothly varying mixer module

Discussion

Mixes 2 inputs into a single output. The mixing gain parameters are exponentially smoothed (first order IIR) at the sample rate, with the smoothingTime parameter determining the smoothing rate for both of the gain values. The variables, gain1 and gain2, specify the target gains for the mixing process. The variables, currentGain1 and currentGain2, specify the instantaneous gains applied, and these exponentially approach the target gains. At build time, currentGain1 is set to gain1 and currentGain2 is set to gain2. This causes the mixers to startup in a converged state.

Module Pack

Standard

ClassID

classID = 94

Type Definition

typedef struct _ModuleSMixer2x1
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
FLOAT32 gain1;                                // Desired gain applied to first input channel.
FLOAT32 gain2;                                // Desired gain applied to second input channel.
FLOAT32 smoothingTime;                        // Time constant of the smoothing process.
FLOAT32 currentGain1;                         // Instantaneous gain for the first input channel.
FLOAT32 currentGain2;                         // Instantaneous gain for the second input channel.
FLOAT32 smoothingCoeff;                       // Smoothing coefficient.
} ModuleSMixer2x1Class;

Variables

Properties

Name	Type	Usage	isHidden	Default Value	Range	Units
gain1	float	parameter	0	1	-10:10
gain2	float	parameter	0	1	-10:10
smoothingTime	float	parameter	0	10	0:1000	msec
currentGain1	float	state	1	1	-10:10	linear
currentGain2	float	state	1	1	-10:10	linear
smoothingCoeff	float	derived	1	0.002081	Unrestricted

Pins

Input Pins


Name	in1
Description	audio input
Data type	{float, int, fract32}
Channel range	Unrestricted
Block size range	Unrestricted
Sample rate range	Unrestricted
Complex support	Real


Name	in2
Description	audio input
Data type	{float, int, fract32}
Channel range	Unrestricted
Block size range	Unrestricted
Sample rate range	Unrestricted
Complex support	Real

Output Pins


Name	out
Description	audio output
Data Type	{float, int, fract32}

Matlab Usage

File Name: smixer2x1_module.m 
 M=smixer2x1_module(NAME) 
 Creates a 2-input 1-output smoothly varying mixer for use in the Audio 
 Weaver environment.   

 Arguments: 
    NAME - name of the module. 

 The module automatically determines the dataType based on the dataType of 
 the input pin. You can explicitly set the data type using an optional 
 second argument: 

 M=smixer2x1_module(NAME, DATATYPE) 
 where DATATYPE is: 'float' or 'fract32'. Explicitly setting the DATATYPE 
 is only required for code generation.