AGCMultiplierFract32

Overview

Mono x N-channel multiplier

Discussion

The AGCFract32 Multiplier is used to multiply N interleaved audio channels by a single mono audio signal.
A common use for the AGCMultipler is in automatic gain control systems, where the gain signal is taken from the limiter core or gain computer module.
Using a single (mono) gain control signal for a multichannel input ensures that the balance between the audio channels is maintained, and allows for sidechain processing.

The postShift parameter can be used to adjust the scaling of the output, or allow multiplies of values larger than 1.

e.g. A postShift of -1 will scale the output between -2 and 2, if the input was between -1 and 1.

The user can multiply 0.75 with a shift of -1 and assume normal scaling and achieve a multiply of 1.5. A positive postShift can increase the dynamic range when multiplying with small numbers. It is up to the user to track all shifts in the layout.

Module Pack

Standard

ClassID

classID = 131

Type Definition

typedef struct _ModuleAGCMultiplierFract32
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
INT32 postShift;                              // Number of bits to shift
} ModuleAGCMultiplierFract32Class;

Variables

Properties

Name	Type	Usage	isHidden	Default Value	Range	Units
postShift	int	parameter	0	7	0:31

Pins

Input Pins


Name	g
Description	Gain to apply
Data type	fract32
Channel range	1:1:1
Block size range	Unrestricted
Sample rate range	Unrestricted
Complex support	Real


Name	in
Description	N-channel audio input signal
Data type	fract32
Channel range	Unrestricted
Block size range	Unrestricted
Sample rate range	Unrestricted
Complex support	Real

Output Pins


Name	out
Description	N-channel audio output signal
Data Type	fract32

Matlab Usage

File Name: agc_multiplier_fract32_module.m 
 M=agc_multiplier_fract32_module(NAME) 
 Creates a 1 x N-channel fractional multiplier module for use with the Audio 
 Weaver.  Arguments: 
    NAME - name of the module.