Re: [Csnd] Bandpass and notch through lowpass and highpass (parameter questions)

Date	2017-11-19 00:25
From	Partev Barr Sarkissian
Subject	Re: [Csnd] Bandpass and notch through lowpass and highpass (parameter questions)
	As in "gain/bandwidth product"? Gain/bandwidth product in a Bandpass Filter: gain of the peak of Q goes up, the bandwidth gets smaller. As the gain goes down, the bandwidth gets wider. Fun to watch this on a scope, back in my analog modular days. -PBS ============================================ --- Victor.Lazzarini@MU.IE wrote: From: Victor Lazzarini <Victor.Lazzarini@MU.IE> To: CSOUND@LISTSERV.HEANET.IE Subject: Re: [Csnd] Bandpass and notch through lowpass and highpass (parameter questions) Date: Wed, 15 Nov 2017 21:15:44 +0000 I guess it depends on the filter, but for resonant lp and hp, the Q value generally is to do with the resonance region, so it would not set the bandwidth of a combined filter, but the separation of the cutoff freqs will. What the Q of the individual filters would change is the resonance peaks at the edge of the pass/stop band. Victor Lazzarini Dean of Arts, Celtic Studies, and Philosophy Maynooth University Ireland On 15 Nov 2017, at 21:09, Jeanette C. <julien@MAIL.UPB.DE> wrote: Hey hey, my understanding is, that both bandpass and bandreject or notch filters can be created by lowpass and highpass filtering a signal in series or in parallel, respectively. My question: how is the q parameter for the resulting filter adjusted? Is it the distance of cutoff frequencies or a change in q-values for the two filters or a combination thereof? If the answer can widely vary, I'm most interested in the answer as would apply to a typical analogue statevariable filter model, as found on a Steiner-Parker filter or in Csound the zdf_2pole or statevar. Alas, my code reading skills are insufficient for an unassisted explanation. Best wishes and thanks for any help, Jeanette -------- * website: http://juliencoder.de - for summer is a state of sound * SoundCloud: https://soundcloud.com/jeanette_c They say, break away - I'm missing out on the fun and games <3 (Britney Spears) Csound mailing list Csound@listserv.heanet.ie https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to https://github.com/csound/csound/issues Discussions of bugs and features can be posted here Csound mailing list Csound@listserv.heanet.ie https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to https://github.com/csound/csound/issues Discussions of bugs and features can be posted here Netscape. Just the Net You Need. Csound mailing list Csound@listserv.heanet.ie https://listserv.heanet.ie/cgi-bin/wa?A0=CSOUND Send bugs reports to https://github.com/csound/csound/issues Discussions of bugs and features can be posted here