Biquad Filter Module

The Biquad Filter Module implements a subtractive synthesis six-coefficient digital IIR filter with input/output power balancing for some pole stability. It takes an input signal and several continuous real-time parameter values and produces a filtered output Signal. Available forms of the filter include: Lowpass, Highpass, Bandpass, Notch, and Allpass. For more information about IIR filter forms and configurations, see Robert Bristow-Johnson's excellent EQ Cookbook.

For a key to understanding the tables on this page, see the Module Types page.

Adding Input Ports

Adding input ports is not enabled for this module.

Static Parameters

#	Title	Type	Description
0	Filter Type	Choice	Has the options Lowpass Highpass Bandpass Notch Allpass

Input Ports

#	Title	Description	Input Scalar Used	Parameter Scalar Used
0	Center Frequency	Indicates the filter center frequency in Hz (cycles per second) for each filter form	YES	YES
1	Q	Indicates the 'Quality value' of the filter	YES	YES
2	(unused)	Future feature placeholder.	N/A	N/A
3	Input Signal	Any input signal.	NO	NO

Output Ports

#	Title	Description
0	Filtered Signal	A filtered and power-balanced version of the Input Signal