Wondering, host based Windows 10, is there a simple configurable HP filter? I am running the Peace GUI on the EQ, and just knock down the lower two octaves. HP at least 4th order, 60 Hz as my desktop speakers are 3 inch Fostex. They are reasonably flat so I don't actually use any other eq. ( modified and tweeter)
Seems over kill. Maybe it makes no difference, but I am one of those where the less is running the happier.
Seems over kill. Maybe it makes no difference, but I am one of those where the less is running the happier.
As you seem to use EqualizerAPO, why not just add two or more HP filters in chain and load the filter as include file (Note: EqualizerAPO build-in filters are 2nd order so two in series does the job you mention). Custom filters feature allows using higher order filters as well but, it's not recommended to use high order implementation with high pass filter at small cutoff frequency (I'd recommend using 1st order filters in series when cut-off frequency is below 100 Hz).
With Octave you can design coefficients for your custom filter quite easy.
With Octave you can design coefficients for your custom filter quite easy.
In addition to my reply, you can calculate the 1st order HP filter directly in config file:
where sampleRate and pi are EqualizerAPO's internal variables.
Code:
Eval: cutoff=60.0
Eval: w=2.0*pi*cutoff/sampleRate
Eval: b0 =cos(w)+1.0
Eval: b1=-(cos(w)+1.0)
Eval: a0=cos(w)+sin(w)+1
Eval: a1=sin(w)-cos(w)-1
# 4th order HP filter
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`where sampleRate and pi are EqualizerAPO's internal variables.
If you feel those sin-cos calls takes too much CPU then here's an approximation which works well below 1kHz cutoff frequencies:
I have not tried how well EqualizerAPO handles those brackets ... .
Code:
Eval: cutoff=60.0
Eval: x=2.0*pi*cutoff/sampleRate
Eval: sx=-5.382643908e-8+x*(1.00000755295+x*(-1.627621479421707e-4+x*(-0.1657084756226908)))
Eval: cx=1.99999946747854+x*(8.3526171644607921e-5+x*(-0.50208137392503+x*1.664302325330385905e-2))
Eval: a0=cx+sx
Eval: a1=sx-cx
Eval: b0=cx
Eval: b1=-cx
# 4th order HP filter
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`
Filter: ON IIR Order 1 Coefficients `b0` `b1` `a0` `a1`I have not tried how well EqualizerAPO handles those brackets ... .