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.

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

Pins

Input Pins

Name: in1

Description: audio input

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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

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