WRLX and WLHX coeffient equations

Algorithm development and general DSP issues

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Sweetalk
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WRLX and WLHX coeffient equations

Post by Sweetalk » Fri May 28, 2021 6:44 am

I was looking for the equations to calculate the WRLX and WRHX coefficents to apply in single pole low and high pass filter but I couldn't find them anywhere. Not in the forum or in the knowledge base. Maybe I'm searching in the wrong way, but someone can point me out in the right direction?.
Also looking for differences between implementing low pass filters with the WRHX instruction or just RDFX

frank
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Re: WRLX and WLHX coeffient equations

Post by frank » Fri May 28, 2021 10:14 am

See this section for calculating K http://www.j8268.com/knowledge_base/ ... le_filters
Frank Thomson
Experimental Noize

Sweetalk
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Re: WRLX and WLHX coeffient equations

Post by Sweetalk » Sat May 29, 2021 2:50 am

I looked into it several times and try to correspond the K2 and -Ks coef to the RDFX and WRHX in a filter.
The RDFX can be calculated Kf = 1- e^(2.pi.freq.t), being t 1/sample rate. There's an aproximation of Kf = 2.pi.F / Fs too
And for the WHRLX/WRLX there's no mention of the coefficient or the -Ks in the knowledge base, not in the instruction list (only mentions that the range of the coef is -2 to +1.99 and for a -1 coef infinite shelve or -0.5 for -6dB).
I think this things should be way more visible and reachable.

gfisys
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Re: WRLX and WLHX coeffient equations

Post by gfisys » Sat May 29, 2021 4:18 am

Rdfx+Wrlx gives you control over the shelving, Rdfx+Wrax does not.

Rdfx+Wrax works only for lowpass, for highpass you need to use Rdfx+Wrhx

Sweetalk
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Re: WRLX and WLHX coeffient equations

Post by Sweetalk » Wed Aug 04, 2021 10:48 am

gfisys wrote:
Sat May 29, 2021 4:18 am
Rdfx+Wrlx gives you control over the shelving, Rdfx+Wrax does not.

Rdfx+Wrax works only for lowpass, for highpass you need to use Rdfx+Wrhx
I saw your answer but never thanked! Thanks!!

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