Low-Pass Filter Component

Controls

Control	Function	Default / Range
Response Panel	The Response panel provides vertical and horizontal cross-hairs with a dynamic frequency and dB read-out. Place the mouse courser over the graph to activate the cross-hairs. When the Phase control is activated, the horizontal cross-hair line to the left of center represents the normal curve, the right side represents the phase curve. The readout is only for the normal curve.	X-Axis = 20 Hz to 20 kHz Y-Axis Left = -24 dB to 24 dB Y Axis Right = -180° to -180°
Phase	Turns the Phase curve on and off.	On/Off
Bypass	Bypasses the filter.	Off/On
Invert	Inverts the output signal.	Normal/Inverted
Mute	Mutes the output signal.	Off/On
Frequency (Hz)	Sets the frequency at which the gain of the output falls to a point 3 dB below the maximum as set by the Gain control. Frequencies above this frequency are attenuated. All frequencies below this frequency are amplified based on the setting of the Gain control.	Default = 1000 Range = 20 to 20000
Q-factor	The Q-factor determines the sharpness of the gain slope as it falls from the cutoff frequency. A Q-factor of 1.00 causes a slight rise above the maximum Gain as the frequencies approach the cutoff frequency, then gradually falls back to the maximum Gain at the cutoff frequency then a constant slope directly from the maximum Gain at the cutoff frequency to -20 dB. The result is a fairly flat amplification of the frequencies below and up to the cutoff frequency then an even fall in gain to -20 dB. A Q-factor of 10 causes a sharp spike of 20 dB higher than the maximum Gain as the frequency approaches the cutoff frequency, then a sharp decline to -20 dB as the frequency increases. The result is the frequencies in a fairly narrow band around the cutoff frequency are amplified above the maximum Gain. A Q-factor of 0.100 causes a very slow, curved slope beginning right at the cutoff frequency up to the maximum Gain. The result is that the frequencies below the cutoff frequency are completely attenuated and the Gain above the cutoff frequency is slowly increased as frequency increases.	Default = 1.00 Range = .100 to 10.00
Gain (dB)	Sets the output Gain.	Default = 0 Range = -100 to 20
Slope (dB per Octave)	Sets the slope at which the gain falls from the level set by the Gain control to -100 dB. You can set the maximum allowed slope in the Properties. The Linkwitz-Riley adjusts in 12 dB per Octave steps, all others adjust in 6 dB per Octave steps.	Default for all = 48 Range: Variable Q = 6 to 60 Butterworth = 6 to 60 Linkwitz-Riley = 12 to 60 Bessel-Thomson = 6 to 60 Chebyshev = 6 to 60
Type	Selects the type of filter.	Butterworth Linkwitz-Riley (Default) Bessel-Thomson Chebyshev
Bessel Normalization	Sets the type of normalization for the Bessel-Thomson filter.	-3 dB Flat Group Delay -3 dB Mirror Magnitude Natural Mirror Magnitude Natural Phase Match

Control

Function

Default / Range

Response Panel

The Response panel provides vertical and horizontal cross-hairs with a dynamic frequency and dB read-out. Place the mouse courser over the graph to activate the cross-hairs. When the Phase control is activated, the horizontal cross-hair line to the left of center represents the normal curve, the right side represents the phase curve. The readout is only for the normal curve.

X-Axis = 20 Hz to 20 kHz

Y-Axis Left = -24 dB to 24 dB

Y Axis Right = -180° to -180°

Phase

Turns the Phase curve on and off.

On/Off

Bypass

Bypasses the filter.

Off/On

Invert

Inverts the output signal.

Normal/Inverted

Mute

Mutes the output signal.

Off/On

Frequency

(Hz)

Sets the frequency at which the gain of the output falls to a point 3 dB below the maximum as set by the Gain control. Frequencies above this frequency are attenuated. All frequencies below this frequency are amplified based on the setting of the Gain control.

Default = 1000

Range = 20 to 20000

Q-factor

The Q-factor determines the sharpness of the gain slope as it falls from the cutoff frequency.

A Q-factor of 1.00 causes a slight rise above the maximum Gain as the frequencies approach the cutoff frequency, then gradually falls back to the maximum Gain at the cutoff frequency then a constant slope directly from the maximum Gain at the cutoff frequency to -20 dB. The result is a fairly flat amplification of the frequencies below and up to the cutoff frequency then an even fall in gain to -20 dB.

A Q-factor of 10 causes a sharp spike of 20 dB higher than the maximum Gain as the frequency approaches the cutoff frequency, then a sharp decline to -20 dB as the frequency increases. The result is the frequencies in a fairly narrow band around the cutoff frequency are amplified above the maximum Gain.

A Q-factor of 0.100 causes a very slow, curved slope beginning right at the cutoff frequency up to the maximum Gain. The result is that the frequencies below the cutoff frequency are completely attenuated and the Gain above the cutoff frequency is slowly increased as frequency increases.

Default = 1.00

Range = .100 to 10.00

Gain

(dB)

Sets the output Gain.

Default = 0

Range = -100 to 20

Slope

(dB per Octave)

Sets the slope at which the gain falls from the level set by the Gain control to -100 dB. You can set the maximum allowed slope in the Properties.

The Linkwitz-Riley adjusts in 12 dB per Octave steps, all others adjust in 6 dB per Octave steps.

Default for all = 48

Range:

Variable Q = 6 to 60

Butterworth = 6 to 60

Linkwitz-Riley = 12 to 60

Bessel-Thomson = 6 to 60

Chebyshev = 6 to 60

Type

Selects the type of filter.

Butterworth

Linkwitz-Riley (Default)

Bessel-Thomson

Chebyshev

Bessel Normalization

Sets the type of normalization for the Bessel-Thomson filter.

-3 dB Flat Group Delay

-3 dB Mirror Magnitude

Natural Mirror Magnitude

Natural Phase Match

Properties

Slope

Property	Function	Choices
Max Slope	Sets the maximum Slope allowable in the Control Panel for all of the filter types.	12, 24, 36, 48, 60, 72, 84, 96 dB/Octave

Property

Function

Choices

Max Slope

Sets the maximum Slope allowable in the Control Panel for all of the filter types.

12, 24, 36, 48, 60, 72, 84, 96

dB/Octave

Channels

Property	Function	Choices
Type	Sets the type of input and output channels	Mono Stereo Multi-Channel
Count	For Multi-Channel, sets the number of channels.	2 to 256

Property

Function

Choices

Type

Sets the type of input and output channels

Mono

Stereo

Multi-Channel

Count

For Multi-Channel, sets the number of channels.

2 to 256

Response Panel

Property	Function	Choices
Enabled	Determines if the Response Panel is visible in the Control Panel	Yes / No
Size	Determines the size of the Response Panel.	Small Medium Large

Property

Function

Choices

Enabled

Determines if the Response Panel is visible in the Control Panel

Yes / No

Size

Determines the size of the Response Panel.

Small

Medium

Large

Control Pins

Pin Name	Value	String	Position	Pins Available
Bypass	0 1	active bypass	0 1	Input / Output
Filter Type	1.00 2.00 3.00 4.00 5.00	Variable Q Butterworth Linkwitz-Riley Bessel-Thomson Chebyshev	0 .25 .50 .75 1.0	Input / Output
Frequency	10.0 to 20,000	10 Hz to 20 kHz	0.000 to 1.00	Input / Output
Gain	-100 to 20	-100 dB to 20 dB	0.000 to 1.00	Input / Output
High-Pass (Bessel-Thomson) Normalization	0 1 2 3	-3 dB Flat Group Delay -3 dB Mirror Magnitude Natural Mirror Magnitude Natural Phase Match	0 .333 .667 1.00	Input / Output
Invert	0 1	normal invert	0 1	Input / Output
Mute	0 1	unmute mute	0 1	Input / Output
Q	.100 to 10.0	.100 to 10.0	0.000 to 1.00	Input / Output
Slope	6.0 12.0 18.0 24.0 30.0 36.0 42.0 48.00 54.0 60.0 66.0 72.0 78.0 84.0 90.0 96.0	6 dB/Oct 12 dB/Oct 18 dB/Oct 24 dB/Oct 30 dB/Oct 36 dB/Oct 42 dB/Oct 48 dB/Oct 54 dB/Oct 60 dB/Oct 66 dB/Oct 72 dB/Oct 78 dB/Oct 84 dB/Oct 90 dB/Oct 96 dB/Oct	0.00 .067 .133 .200 .267 .333 .400 .467 .533 .600 .667 .733 .800 .867 .933 1.00	Input / Output

Pin Name

Value

String

Position

Pins Available

Bypass

active

bypass

Input / Output

Filter Type

1.00

2.00

3.00

4.00

5.00

Variable Q

Butterworth

Linkwitz-Riley

Bessel-Thomson

Chebyshev

.25

.50

.75

1.0

Input / Output

Frequency

10.0 to 20,000

10 Hz to 20 kHz

0.000 to 1.00

Input / Output

Gain

-100 to 20

-100 dB to 20 dB

0.000 to 1.00

Input / Output

High-Pass (Bessel-Thomson) Normalization

-3 dB Flat Group Delay

-3 dB Mirror Magnitude

Natural Mirror Magnitude

Natural Phase Match

.333

.667

1.00

Input / Output

Invert

normal

invert

Input / Output

Mute

unmute

mute

Input / Output

.100 to 10.0

0.000 to 1.00

Input / Output

Slope

6.0

12.0

18.0

24.0

30.0

36.0

42.0

48.00

54.0

60.0

66.0

72.0

78.0

84.0

90.0

96.0

6 dB/Oct

12 dB/Oct

18 dB/Oct

24 dB/Oct

30 dB/Oct

36 dB/Oct

42 dB/Oct

48 dB/Oct

54 dB/Oct

60 dB/Oct

66 dB/Oct

72 dB/Oct

78 dB/Oct

84 dB/Oct

90 dB/Oct

96 dB/Oct

0.00

.067

.133

.200

.267

.333

.400

.467

.533

.600

.667

.733

.800

.867

.933

1.00

Input / Output

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