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comb~

Apply a comb filter effect

Description

Use the comb~ object to apply the classic comb filtering effect to an audio input. The comb~ object mixes the current input sample with earlier input and/or output samples, according to the formula:

yn = axn + bxn-(DR/1000) + cyn-(DR/1000)

where R is the sampling rate and D is a delay time in milliseconds.

Examples

Filter parameters may be supplied as float values or as signals

Arguments

max-delay [float]

Optional
Unitsms

The maximum delay time. Defaults to 10 ms if not specified.

initial-delay [float]

Optional
Unitsms

Initial delay time

gain-coefficient [float]

Optional

Gain coefficient

feedforward-coefficient [float]

Optional

The feedforward coefficient

feedback-coefficient [float]

Optional

The feedback coefficient

Attributes

Common Box Attributes

annotation [symbol]

Sets the text that will be displayed in the Clue window when the user moves the mouse over the object.

background [int] (default: 0)

Adds or removes the object from the patcher's background layer. background 1 adds the object to the background layer, background 0 removes it. Objects in the background layer are shown behind all objects in the default foreground layer.

color [4 floats]

Sets the color for the object box outline.

fontface [int]

Sets the type style used by the object. The options are:

plain
bold
italic
bold italic

Possible values:

0 = 'regular'
1 = 'bold'
2 = 'italic'
3 = 'bold italic'

fontname [symbol]

Sets the object's font.

fontsize [float]

Sets the object's font size (in points).

Possible values:

'8'
'9'
'10'
'11'
'12'
'13'
'14'
'16'
'18'
'20'
'24'
'30'
'36'
'48'
'64'
'72'

hidden [int] (default: 0)

Toggles whether an object is hidden when the patcher is locked.

hint [symbol]

Sets the text that will be displayed in as a pop-up hint when the user moves the mouse over the object in a locked patcher.

ignoreclick [int] (default: 0)

Toggles whether an object ignores mouse clicks in a locked patcher.

patching_rect [4 floats] (default: 0. 0. 100. 0.)

Sets the position and size of the object in the patcher window.

position [2 floats]

g/s(set)

Sets the object's x and y position in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its size unchanged.

presentation [int] (default: 0)

Sets whether an object belongs to the patcher's presentation.

presentation_rect [4 floats] (default: 0. 0. 0. 0.)

Sets the x and y position and width and height of the object in the patcher's presentation, leaving its patching position unchanged.

rect [4 floats]

g/s(set)

Sets the x and y position and width and height of the object in both patching and presentation modes (if the object belongs to its patcher's presentation).

size [2 floats]

g/s(set)

Sets the object's width and height in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its position unchanged.

textcolor [float]

Sets the color for the object's text in RGBA format.

textjustification [int]

Text Justification

Possible values:

0 = 'left'
1 = 'center'
2 = 'right'

varname [symbol]

Sets the patcher's scripting name, which can be used to address the object by name in pattr, scripting messages to thispatcher, and the js object.

Messages

float

Arguments

filter-parameters [float]
2nd inlet: delay time in milliseconds
3rd inlet: gain coefficient
4th inlet: feedforward coefficient
Right inlet: feedback coefficient

clear

Reset filter state to zero internal feedback

signal

Left inlet: signal to be filtered
2nd inlet: delay time in milliseconds
3rd inlet: gain coefficient
4th inlet: feedforward coefficient
Right inlet: feedback coefficient

Output

signal

The filtered signal.

See Also

Name Description
Sound Processing Techniques Sound Processing Techniques
allpass~ Apply an allpass filter effect
delay~ Delay a signal
reson~ Resonant bandpass filter
teeth~ Comb filter with feedforward and feedback delay control
MSP Delay Tutorial 6: Comb Filter MSP Delay Tutorial 6: Comb Filter
Audio Filtering Audio Filtering