I have the PDF. The cool thing about this paper which is not mentioned in the abstract is the least-squares fit to the spectrum magnitude of an arbitrary 2-pole filter, giving a very nice biquad with no need for oversampling to get a good nyquist response. I have some matlab/octave code for this somewhere... I made an EQ using this many years ago.
-D On Nov 27, 2011, at 2:29 PM, robert bristow-johnson wrote: > On 11/27/11 3:17 PM, Dominique Würtz wrote: >> >>>> Any ideas? >>> Knud Christensen "A Generalization of the Biquadratic Parametric" >>> http://www.aes.org/e-lib/browse.cfm?elib=12429 >>> >> Hmm, reading the abstract I'm not 100% sure if it really addresses what >> I'm aiming at. Sorry for being sceptical, but before I shell out 20$ for >> this, can you confirm me that it actually considers the gain correction >> at Nyquist? >> > what it does is inverse-map the 5 coefficients of the biquad filter to 5 > parameters that users might find useful. there *are* only 5 degrees of > freedom, so it really is only an issue for how you want those 5 control knobs > defined. > > why not put out a request for anyone here at music-dsp who has free access to > the full AES archives (i don't, sorry) to send you the pdf? maybe there is a > similar paper by the author living out there in the internet. maybe you can > find and contact the author. i have a paper copy of the preprint > *somewhere*, but i am not sure where. > > L8r, > > -- > > r b-j r...@audioimagination.com > > "Imagination is more important than knowledge." > > > > -- > dupswapdrop -- the music-dsp mailing list and website: > subscription info, FAQ, source code archive, list archive, book reviews, dsp > links > http://music.columbia.edu/cmc/music-dsp > http://music.columbia.edu/mailman/listinfo/music-dsp -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp
