Single-Band Parametric EQ
Second-order parametric equalizer filter
Libraries:
Audio Toolbox /
Filters
Description
The Single-Band Parametric EQ block filters each channel of the input signal
over time using a specified center frequency, bandwidth, and peak (dip) gain. This block
offers tunable filter design parameters, which enable you to tune the filter
characteristics while the simulation is running. The filter is designed using designParamEQ
and implemented using dsp.SOSFilter
.
This block supports variable-size input, enabling you to change the channel length during simulation. To enable variable-size input, clear the Inherit sample rate from input parameter. The number of channels must remain constant.
Examples
Perform Parametric Equalization
Examine the Single-Band Parametric EQ block in a Simulink® model and tune parameters.
Ports
Input
x — Input signal
matrix | 1-D vector
Matrix input –– Each column of the input is treated as an independent channel.
1-D vector input –– The input is treated as a signal channel.
This port is unnamed unless you specify additional input ports.
Data Types: single
| double
Fc — Center frequency (Hz)
scalar
Specify the center frequency as a positive scalar that is less than half the sample rate of the input signal.
Dependencies
To enable this port, select Specify from input port for the Center Frequency (Hz) parameter.
Data Types: single
| double
BW — Bandwidth (Hz)
scalar
Specify the filter bandwidth as a positive scalar that is less than or equal to half the sample rate of the input signal and 20 kHz.
Dependencies
To enable this port, select Bandwidth and Center
Frequency
for the Filter
specification and Specify from input
port for the Filter Bandwidth
(Hz) parameter.
Data Types: single
| double
GdB — Peak or dip gain (dB)
scalar
Specify the peak or dip gain in dB as a scalar.
Dependencies
To enable this port, select Specify from input port for the Peak Gain (dB) parameter.
Data Types: single
| double
Q — Quality factor
scalar
Specify the quality factor as a positive scalar.
Dependencies
To enable this port, select Quality factor and center
frequency
for the Filter
Specification and Specify from input
port for the Quality Factor
parameter.
Data Types: single
| double
Output
Port_1 — Output signal
matrix
The Single-Band Parametric EQ block outputs a signal with the same data type as the input signal. The size of the output depends on the size of the input:
Matrix input –– The block outputs a matrix the same size and data type as the input signal.
1-D vector input –– The block outputs an N-by-1 matrix (column vector), where N is the number of elements in the 1-D vector.
Data Types: single
| double
Parameters
If a parameter is listed as tunable, then you can change its value during simulation.
Filter order — Order of filter
2
(default) | positive even scalar
Tunable: No
Filter specification — Specify parameters used to design filter
Bandwidth and center
frequency
(default) | Quality factor and center frequency
Bandwidth and center frequency
–– Design the filter using Filter Bandwidth (Hz), Center Frequency (Hz), and Peak Gain (dB).Quality factor and center frequency
–– Design the filter using Center Frequency (Hz), Peak Gain (dB), and Quality Factor.
Tunable: No
Center Frequency (Hz) — Center frequency of filter
11025
(default) | positive scalar
Specify the center frequency as a positive scalar that is less than half the sample rate of the input signal.
To specify Center Frequency (Hz) from an input port, select Specify from input port for the parameter.
Tunable: Yes
Filter Bandwidth (Hz) — Bandwidth of filter
2205
(default) | positive scalar in the range [0, max(fs/2, 20,000)]
Specify the filter bandwidth as a positive scalar that is less than or equal to half the sample rate of the input signal or 20 kHz, whichever is larger.
To specify Filter Bandwidth (Hz) from an input port, select Specify from input port for the parameter.
Tunable: Yes
Dependencies
To enable this parameter, set Filter
specification to Bandwidth and center
frequency
.
Quality Factor — Quality factor
5
(default) | scalar in the range [0.1, 20]
Specify the quality factor as a scalar in the range [0.1, 20].
To specify Quality Factor from an input port, select Specify from input port for the parameter.
Tunable: Yes
Dependencies
To enable this parameter, set Filter
specification to Quality factor and center
frequency
.
Peak Gain (dB) — Peak or dip gain of filter
6.0206
(default) | scalar in the range [−30, 30]
Specify the peak gain in dB as a scalar in the range [−30, 30].
Tunable: Yes
Inherit sample rate from input — Specify source of input sample rate
on (default) | off
When you select this parameter, the block inherits its sample rate from the input signal. When you clear this parameter, you specify the sample rate in Input sample rate (Hz).
Tunable: No
Input sample rate (Hz) — Sample rate of input
44100
(default) | scalar
Tunable: Yes
Dependencies
To enable this parameter, clear the Inherit sample rate from input parameter.
Simulate using — Specify type of simulation to run
Code generation
(default) | Interpreted execution
Interpreted execution
–– Simulate model using the MATLAB® interpreter. This option shortens startup time and has simulation speed comparable toCode generation
. In this mode, you can debug the source code of the block.Code generation
–– Simulate model using generated C code. The first time you run a simulation, Simulink® generates C code for the block. The C code is reused for subsequent simulations, as long as the model does not change. This option requires additional startup time, but the speed of the subsequent simulations is faster compared toInterpreted execution
.
Tunable: No
Block Characteristics
Data Types |
|
Direct Feedthrough |
|
Multidimensional Signals |
|
Variable-Size Signals |
|
Zero-Crossing Detection |
|
References
[1] Orfanidis, Sophocles J. "High-Order Digital Parametric Equalizer Design." Journal of the Audio Engineering Society. Vol. 53, November 2005, pp. 1026–1046.
Extended Capabilities
C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.
Version History
Introduced in R2019aR2022b: Input sample rate (Hz) parameter is tunable
You can change the value of the Input sample rate (Hz) parameter during simulation.
MATLAB Command
You clicked a link that corresponds to this MATLAB command:
Run the command by entering it in the MATLAB Command Window. Web browsers do not support MATLAB commands.
Select a Web Site
Choose a web site to get translated content where available and see local events and offers. Based on your location, we recommend that you select: .
You can also select a web site from the following list:
How to Get Best Site Performance
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.
Americas
- América Latina (Español)
- Canada (English)
- United States (English)
Europe
- Belgium (English)
- Denmark (English)
- Deutschland (Deutsch)
- España (Español)
- Finland (English)
- France (Français)
- Ireland (English)
- Italia (Italiano)
- Luxembourg (English)
- Netherlands (English)
- Norway (English)
- Österreich (Deutsch)
- Portugal (English)
- Sweden (English)
- Switzerland
- United Kingdom (English)