Leveler Component

Automatic Gain Control (AGC) Component

The purpose of the Automatic Gain Control is to control the overall dynamic range of the Output when the Input level changes.

The AGC can be adjusted from unity (1:1) with the Input, to an almost flat (100:1 - very little amplitude variation) Output. The AGC automatically adjusts the Gain to compensate for high or low Inputs. The control settings for the AGC Component affect all the Input Channels based on calculations made using the highest Input level. If you want to separately control the AGC for multiple Channels, simply add more AGC Components.

Controls

General

Control	Function	Default/Range
In Gain (dB)	The Input Gain adds to the level of the Input source.	Default = 0 Range -20 to 20
Detector (dB)	Graphically and numerically displays the RMS level of the highest Input.	-60 to 20
Response Panel	Graphically represents the Gain Calculations for the Channel having the highest Input RMS level. X axis represents the Input Y axis represents the Output The red dot represents the Output Level. Below the Threshold Level the Output is equal to the Input, above the Threshold level it is adjusted by the AGC.	X axis -60 to 20 Y axis -60 to 20
Bypass	Bypasses the AGC functionality.	Off/On
Applied Gain (dB)	Graphically and numerically displays the amount of Gain applied to the Channel with the highest RMS Input level. The same amount of Gain, calculated on the highest Channel, is applied to all other channels that are above the Threshold Level regardless of their relation to the Target Level. Graphically the meter starts in the middle, displaying attenuation in red going down from center, and gain in green going up from center.	-60 to 20
Out Gain (dB)	Controls the output level.	-20 to 20

Control

Function

Default/Range

In Gain

(dB)

The Input Gain adds to the level of the Input source.

Default = 0

Range -20 to 20

Detector

(dB)

Graphically and numerically displays the RMS level of the highest Input.

-60 to 20

Response Panel

Graphically represents the Gain Calculations for the Channel having the highest Input RMS level.

X axis represents the Input

Y axis represents the Output

The red dot represents the Output Level. Below the Threshold Level the Output is equal to the Input, above the Threshold level it is adjusted by the AGC.

X axis -60 to 20

Y axis -60 to 20

Bypass

Bypasses the AGC functionality.

Off/On

Applied Gain

(dB)

Graphically and numerically displays the amount of Gain applied to the Channel with the highest RMS Input level. The same amount of Gain, calculated on the highest Channel, is applied to all other channels that are above the Threshold Level regardless of their relation to the Target Level.

Graphically the meter starts in the middle, displaying attenuation in red going down from center, and gain in green going up from center.

-60 to 20

Out Gain

(dB)

Controls the output level.

-20 to 20

Gain Calculations

Control	Function	Default/Range
Threshold Level (dBFS)	The level at which the AGC Component becomes active. This should be set at a level so that the anticipated background noise does not activate the AGC. When an Input exceeds the Threshold Level, the Gain for that input is adjusted to calculated level based on the Ratio and the Target Level. If there is more than one Input that exceeds the Threshold Level, the Gain is calculated using the Channel with the highest RMS level. The other Channel(s) have the same amount of Gain applied to them as the Channel with highest RMS Input level.	Default = -30 Range = -60 to 20
Ratio	The ratio between the Input and the Output as measured from the Target Level. The closer the Ratio is to 100, the closer the Output will be to the Target Level, which also means smaller dynamic changes in the Output level. When the Input is below the Target Level and the Gain applied by the Ratio setting is greater than the Maximum Gain setting, the Output is clipped per the Maximum Gain setting.	Default = 100 Range = 1.0 to 100
Target Level (dB)	Sets the point from which the Gain is calculated based on the Ratio setting. Assuming only one Input, a level below the Target Level has a positive Gain applied, a level above the Target Level has a negative Gain (attenuation) applied. If the Target Level is -15 dB Ratio is 2.5 Input level is 10 dB Adjusted Output is (((Input level - Target Level) / Ratio) + Target Level) = Output Level ((10 dB - (-15 dB) / 2.5) + (-15 dB)) = -5 dB	Default = -200 Range =-60 to 20
Maximum Gain (dB)	Sets the maximum amount of gain provided to an Input when the Input is above the Threshold Level, but below the Target Level. The Maximum Gain is not used when the gain applied by the Ratio setting is less than the Maximum Gain setting. Ratio calculation used Threshold Level is -50 dB Target Level is -15 dB Ratio is 2 (2:1) Maximum Gain is 10 dB Input is -20 dB Adjusted Output is -17.5 dB ((( Input level - Target Level) / Ratio) + Target Level) = Output Level ((-20 dB - (-15 dB) / 2) + (-15 dB)) = -17.5 dB The applied gain is 2.5 dB, which is less than the 10 dB Maximum Gain. Maximum Gain used Maximum Gain is 10 dB Input is -40 dB ((( Input level - Target Level) / Ratio) + Target Level) = Output Level ((-40 dB - (-15 dB) / 2) + (-15 dB)) = -27.5 dB would be a gain of 12.5 dB based on the Ratio Adjusted Output is actually -30 dB a gain of 10 dB, which is equal to the Maximum Gain setting of 10 dB. The same calculation is used, but the Output is clipped at the Maximum Gain setting.	Default = 10 Range = 0 to 20

Control

Function

Default/Range

Threshold Level

(dBFS)

The level at which the AGC Component becomes active. This should be set at a level so that the anticipated background noise does not activate the AGC. When an Input exceeds the Threshold Level, the Gain for that input is adjusted to calculated level based on the Ratio and the Target Level.

If there is more than one Input that exceeds the Threshold Level, the Gain is calculated using the Channel with the highest RMS level. The other Channel(s) have the same amount of Gain applied to them as the Channel with highest RMS Input level.

Default = -30

Range = -60 to 20

Ratio

The ratio between the Input and the Output as measured from the Target Level. The closer the Ratio is to 100, the closer the Output will be to the Target Level, which also means smaller dynamic changes in the Output level.

When the Input is below the Target Level and the Gain applied by the Ratio setting is greater than the Maximum Gain setting, the Output is clipped per the Maximum Gain setting.

Default = 100

Range = 1.0 to 100

Target Level

(dB)

Sets the point from which the Gain is calculated based on the Ratio setting. Assuming only one Input, a level below the Target Level has a positive Gain applied, a level above the Target Level has a negative Gain (attenuation) applied.

If the

Target Level is -15 dB
Ratio is 2.5
Input level is 10 dB
Adjusted Output is
(((Input level - Target Level) / Ratio) + Target Level) = Output Level
((10 dB - (-15 dB) / 2.5) + (-15 dB)) = -5 dB

Default = -200

Range =-60 to 20

Maximum Gain

(dB)

Sets the maximum amount of gain provided to an Input when the Input is above the Threshold Level, but below the Target Level. The Maximum Gain is not used when the gain applied by the Ratio setting is less than the Maximum Gain setting.

Ratio calculation used

Threshold Level is -50 dB
Target Level is -15 dB
Ratio is 2 (2:1)
Maximum Gain is 10 dB
Input is -20 dB
Adjusted Output is -17.5 dB
((( Input level - Target Level) / Ratio) + Target Level) = Output Level
((-20 dB - (-15 dB) / 2) + (-15 dB)) = -17.5 dB
The applied gain is 2.5 dB, which is less than the 10 dB Maximum Gain.

Maximum Gain used

Maximum Gain is 10 dB
Input is -40 dB
((( Input level - Target Level) / Ratio) + Target Level) = Output Level
((-40 dB - (-15 dB) / 2) + (-15 dB)) = -27.5 dB
would be a gain of 12.5 dB based on the Ratio
Adjusted Output is actually -30 dB a gain of 10 dB, which is equal to the Maximum Gain setting of 10 dB. The same calculation is used, but the Output is clipped at the Maximum Gain setting.

Default = 10

Range = 0 to 20

Time Constants

Control	Function	Default/Range
Detector Time (seconds)	Available only when Detector Time Property is set to Use Control. Adjusts the time constant that determines the rate of change of the Detector level in response to changes in the Input signal. This adjustment is to prevent changes (spikes, low frequency signals) in the Input from causing unwanted, momentary output. A fast Detector Time may result in an Output that rapidly fluctuates.	Default = 0.02 Range = 0.0001 to 0.1
Response Time (seconds)	Adjusts the time constant that determines the time it takes for the Gain to go from its current level to the new level when there is a change in the Input RMS level.	Default = 1 Range = 0.1 to 10
Hold Time (seconds)	When the Recovery button is engaged, Hold Time sets minimum time the applied Gain stays at the calculated level after the RMS Input level drops below the Threshold Level. This is to prevent the Output from fluctuating due to momentary pauses in the Input. If there is another Channel in use with a lower RMS Input level, above the Threshold Level, the Hold Time does not apply. The applied Gain changes to the proper level for the new Channel based on the Response Time.	Default = 1 Range = 0 to 10
Recovery Time (seconds)	When the Recovery button is engaged, Recovery Time sets the time it takes for the applied Gain to return to zero. If there is another Channel in use with a lower RMS Input level, above the Threshold Level, the Recovery Time does not apply. The applied Gain changes to the proper level for the new Channel based on the Response Time.	Default = 1 Range = 0.1 to 10
Recovery Enable	Turns on and off the Recovery Time Enable functionality. In the Off position, the Hold Time and Recovery Time do not apply. If there is only one Channel above the Threshold Level, and the Recovery button is in the Off position, when that Channel drops below the Threshold Level, the Gain stays at the last calculated level before the Channel dropped below the Threshold Level.	Off/On

Control

Function

Default/Range

Detector Time

(seconds)

Available only when Detector Time Property is set to Use Control.

Adjusts the time constant that determines the rate of change of the Detector level in response to changes in the Input signal. This adjustment is to prevent changes (spikes, low frequency signals) in the Input from causing unwanted, momentary output. A fast Detector Time may result in an Output that rapidly fluctuates.

Default = 0.02

Range = 0.0001 to 0.1

Response Time

(seconds)

Adjusts the time constant that determines the time it takes for the Gain to go from its current level to the new level when there is a change in the Input RMS level.

Default = 1

Range = 0.1 to 10

Hold Time

(seconds)

When the Recovery button is engaged, Hold Time sets minimum time the applied Gain stays at the calculated level after the RMS Input level drops below the Threshold Level. This is to prevent the Output from fluctuating due to momentary pauses in the Input.

If there is another Channel in use with a lower RMS Input level, above the Threshold Level, the Hold Time does not apply. The applied Gain changes to the proper level for the new Channel based on the Response Time.

Default = 1

Range = 0 to 10

Recovery Time

(seconds)

When the Recovery button is engaged, Recovery Time sets the time it takes for the applied Gain to return to zero.

If there is another Channel in use with a lower RMS Input level, above the Threshold Level, the Recovery Time does not apply. The applied Gain changes to the proper level for the new Channel based on the Response Time.

Default = 1

Range = 0.1 to 10

Recovery Enable

Turns on and off the Recovery Time Enable functionality. In the Off position, the Hold Time and Recovery Time do not apply.

If there is only one Channel above the Threshold Level, and the Recovery button is in the Off position, when that Channel drops below the Threshold Level, the Gain stays at the last calculated level before the Channel dropped below the Threshold Level.

Off/On

Properties

AGC

Property	Function	Choices
Side Chain Input	Provides one Side Chain input per Channel. The Side Chain allows you to filter a signal before using it to control the Gain of the unfiltered audio Input. In Gain is always applied to the Side Chain input signal, regardless of the state of Bypass. NOTE: If you select Side Chain Input = Yes, and don't use the Side Chain Inputs, you will not have any AGC.	No / Yes
Detector Time	Sets one of three pre-set times, or enables the Detector Time control in the Control Panel. If one of the three pre-set times is chosen, the control is not available in the Control Panel. Adjusts the time constant that determines the rate of change of the Detector level in response to changes in the Input signal. This adjustment is to prevent changes (spikes, low frequency signals) in the Input from causing unwanted, momentary output. A fast Detector Time may result in an Output that rapidly fluctuates.	Use Control 10ms 20ms 50ms
Bypass Gain Meter	When set to Active, the Applied Gain meter is active regardless of the state of the Bypass button. This means you can adjust the AGC in Bypass mode. When set to Inactive, the Applied Gain meter is inactive to indicate that the component is in Bypass mode.	Active Inactive

Property

Function

Choices

Side Chain Input

Provides one Side Chain input per Channel. The Side Chain allows you to filter a signal before using it to control the Gain of the unfiltered audio Input.

In Gain is always applied to the Side Chain input signal, regardless of the state of Bypass.

NOTE: If you select Side Chain Input = Yes, and don't use the Side Chain Inputs, you will not have any AGC.

No / Yes

Detector Time

Sets one of three pre-set times, or enables the Detector Time control in the Control Panel. If one of the three pre-set times is chosen, the control is not available in the Control Panel.

Use Control

10ms

20ms

50ms

Bypass Gain Meter

When set to Active, the Applied Gain meter is active regardless of the state of the Bypass button. This means you can adjust the AGC in Bypass mode.

When set to Inactive, the Applied Gain meter is inactive to indicate that the component is in Bypass mode.

Active

Inactive

Channels

Property	Function	Choices
Type	Sets the type of Channel available for Inputs and Outputs.	Mono Stereo Multi-Channel
Count	Sets the number of Channels for Multi-channel.	2 to 256

Property

Function

Choices

Type

Sets the type of Channel available for Inputs and Outputs.

Mono

Stereo

Multi-Channel

Count

Sets the number of Channels for Multi-channel.

2 to 256

Control Pins

The available Control Pins depend on settings in Properties.

Pin Name	Value	String	Position	Pins Available
Applied Gain	-20 to 20	-20 dB to 20 dB	0.000 to 1.00	Output
Bypass	0 1	active bypass	0 1	Input / Output
Detector Level	-100 to 20	-100 dB to 20 dB	0.000 to 1.00	Output
Detector Time	0.100 to 60	100 ms to 60 s	0.000 to 1.00	Input / Output
Hold Time	0.000 to 10	100 ms to 10 s	0.000 to 1.00	Input / Output
Input Gain	-20.0 to 20.0	-20.0 dB to 20.0 dB	0.000 to 1.00	Input / Output
Maximum Gain	0.000 to 20.0	0 dB to 20.0 dB	0.000 to 1.00	Input / Output
Output Gain	-20.0 to 20.0	-20.0 dB to 20.0 dB	0.000 to 1.00	Input / Output
Ratio	1.00 to 100	1.00 to 100	0.000 to 1.00	Input / Output
Recovery	0 1	active bypass	0 1	Input / Output
Recovery Time	0.100 to 10	100 ms to 10 s	0.000 to 1.00	Input / Output
Response Time	0.100 to 10	100 ms to 10 s	0.000 to 1.00	Input / Output
Target Level	-60 to 20	-60 dB to 20 dB	0.000 to 1.00	Input / Output
Threshold Level	-60 to 20	-60 dB to 20 dB	0.000 to 1.00	Input / Output

Pin Name

Value

String

Position

Pins Available

Applied Gain

-20 to 20

-20 dB to 20 dB

0.000 to 1.00

Output

Bypass

active

bypass

Input / Output

Detector Level

-100 to 20

-100 dB to 20 dB

0.000 to 1.00

Output

Detector Time

0.100 to 60

100 ms to 60 s

0.000 to 1.00

Input / Output

Hold Time

0.000 to 10

100 ms to 10 s

0.000 to 1.00

Input / Output

Input Gain

-20.0 to 20.0

-20.0 dB to 20.0 dB

0.000 to 1.00

Input / Output

Maximum Gain

0.000 to 20.0

0 dB to 20.0 dB

0.000 to 1.00

Input / Output

Output Gain

-20.0 to 20.0

-20.0 dB to 20.0 dB

0.000 to 1.00

Input / Output

Ratio

1.00 to 100

0.000 to 1.00

Input / Output

Recovery

active

bypass

Input / Output

Recovery Time

0.100 to 10

100 ms to 10 s

0.000 to 1.00

Input / Output

Response Time

0.100 to 10

100 ms to 10 s

0.000 to 1.00

Input / Output

Target Level

-60 to 20

-60 dB to 20 dB

0.000 to 1.00

Input / Output

Threshold Level

-60 to 20

-60 dB to 20 dB

0.000 to 1.00

Input / Output

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