Hey list,
I just did a search in the list-archive and, yes, I realize that there was a dicussion on biquad~ back in April, but the thread referred to a link that is now broken. Suffice to say, it seems the programming of this external could be a bit more user-friendly, targeted toward the people who are likely to actually USE pd, not people with advanced degrees in math. (If you fall into both categories, more power to ya). If I could just get some help here, I'd like:
f(x, a) = (ff1, ff2, ff3, fb1, fb2) where these are the biquad coefficients for x = notch frequency and a = attenuation
While I understand how it's useful to have tools for building filters in any DSP software, it's too bad this isn't also wrapped up as a more straightforward notch filter. Or maybe I'm just being a wuss here. I'm sure there's someone out there who could implement this as an external.
Thanks,
David
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homepage: http://www.davidgolightly.net
On Mon, Nov 07, 2005 at 04:51:19PM -0500, david golightly wrote:
Hey list,
I just did a search in the list-archive and, yes, I realize that there was a dicussion on biquad~ back in April, but the thread referred to a link that is now broken. Suffice to say, it seems the programming of this external could be a bit more user-friendly, targeted toward the people who are likely to actually USE pd, not people with advanced degrees in math.
(If you fall into both categories, more power to ya). If I could just get some help here, I'd like:f(x, a) = (ff1, ff2, ff3, fb1, fb2) where these are the biquad coefficients for x = notch frequency and a = attenuation
While I understand how it's useful to have tools for building filters in any DSP software, it's too bad this isn't also wrapped up as a more straightforward notch filter.
it is, see /externals/ggee/filters in CVS.. theres a helper object for most of the RBJ biquad types.. i also pasted his formules into a tk script, http://whats-your.name/pd/gui/filter.gif see /extensions/gui/ix/filter.wid.
and no, i dont understand the math either, has somethign to do with rectangular-to-polar conversions i think (but for some reason at least in the commercial filter plugins which use biquad its never shown this way)..
Or maybe I'm just being a wuss here. I'm sure there's someone out there who could implement this as an external.
Thanks,
David
- ---=---^--- -^- -=- - - ^------ - -^---^- -- --^^ --===
homepage: http://www.davidgolightly.net
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
Thanks, Carmen, that's really informative - exactly what I'm looking for.
David
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homepage: http://www.davidgolightly.net
From: carmen ix@replic.net To: pd-list@iem.at Subject: Re: [pd] biquad~ yet again Date: Mon, 7 Nov 2005 22:10:24 +0000
On Mon, Nov 07, 2005 at 04:51:19PM -0500, david golightly wrote:
Hey list,
I just did a search in the list-archive and, yes, I realize that there
was
a dicussion on biquad~ back in April, but the thread referred to a link that is now broken. Suffice to say, it seems the programming of this external could be a bit more user-friendly, targeted toward the people
who
are likely to actually USE pd, not people with advanced degrees in math. (If you fall into both categories, more power to ya). If I could just
get
some help here, I'd like:
f(x, a) = (ff1, ff2, ff3, fb1, fb2) where these are the biquad coefficients for x = notch frequency and a = attenuation
While I understand how it's useful to have tools for building filters in any DSP software, it's too bad this isn't also wrapped up as a more straightforward notch filter.
it is, see /externals/ggee/filters in CVS.. theres a helper object for most of the RBJ biquad types.. i also pasted his formules into a tk script, http://whats-your.name/pd/gui/filter.gif see /extensions/gui/ix/filter.wid.
and no, i dont understand the math either, has somethign to do with rectangular-to-polar conversions i think (but for some reason at least in the commercial filter plugins which use biquad its never shown this way)..
Or maybe I'm just being a wuss here. I'm sure there's someone out there who could implement this as an external.
Thanks,
David
- ---=---^--- -^- -=- - - ^------ - -^---^- -- --^^ --===
homepage: http://www.davidgolightly.net
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
PD-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
-
carmen -
david golightly