fdesign.parameq
(To be removed) Parametric equalizer filter specification
Compatibility
Note
The fdesign.parameq
filter specification object will be
removed in a future release. Existing instances of the object continue to run. For
new code, use the designParamEQ
function instead. For
more information, see Compatibility Considerations.
Syntax
d = fdesign.parameq(spec, specvalue1, specvalue2,
...)
d = fdesign.parameq(... fs)
Description
d = fdesign.parameq(spec, specvalue1, specvalue2,
...)
constructs
a parametric equalizer filter design object, where spec
is a non-case
sensitive character vector. The choices for spec
are as follows:
'F0, BW, BWp, Gref, G0, GBW, Gp'
(minimum order default)'F0, BW, BWst, Gref, G0, GBW, Gst'
'F0, BW, BWp, Gref, G0, GBW, Gp, Gst'
'N, F0, BW, Gref, G0, GBW'
'N, F0, BW, Gref, G0, GBW, Gp'
'N, F0, Fc, Qa, G0'
'N, F0, Fc, S, G0'
'N, F0 ,BW, Gref, G0, GBW, Gst'
'N, F0, BW, Gref, G0, GBW, Gp, Gst'
'N, Flow, Fhigh, Gref, G0, GBW'
'N, Flow, Fhigh, Gref, G0, GBW, Gp'
'N, Flow, Fhigh, Gref, G0, GBW, Gst'
'N, Flow, Fhigh, Gref, G0, GBW, Gp, Gst'
where the parameters are defined as follows:
Parameter | Definition | Unit |
---|---|---|
BW | Bandwidth | |
BWp | Passband Bandwidth | |
BWst | Stopband Bandwidth | |
Gref | Reference Gain | decibels |
G0 | Center Frequency Gain | decibels |
GBW | Gain at which Bandwidth (BW ) is
measured | decibels |
Gp | Passband Gain | decibels |
Gst | Stopband Gain | decibels |
N | Filter Order | |
F0 | Center Frequency | |
Fc | Cutoff Frequency | |
Fhigh | Higher Frequency at Gain GBW | |
Flow | Lower Frequency at Gain GBW | |
Qa | Quality Factor | |
S | Slope Parameter for Shelving Filters |
Regardless of the specification chosen, there are some conditions that apply to the specification parameters. These are as follows:
Specifications for parametric equalizers must be given in decibels
To boost the input signal, set
G0 > Gref
; to cut, setGref > G0
For boost:
G0 > Gp > GBW > Gst > Gref
; For cut:G0 < Gp < GBW < Gst < Gref
Bandwidth must satisfy:
BWst > BW > BWp
d = fdesign.parameq(... fs)
adds the input sampling frequency.
fs
must be specified as a scalar trailing the other numerical
values provided, and is assumed to be in Hz.