[Csnd-dev] FYI: ZDF Filters

Date	2017-04-04 17:43
From	Steven Yi
Subject	[Csnd-dev] FYI: ZDF Filters
	Hi All, Just FYI, now that it's easy for me to develop with Visual Studio, I'm starting work on translating those zero-delay feedback filters (the ones by Will Pirkle that I had done UDO versions) to C in Csound. I've just pushed the first commit which has the zdf_ladder. A couple things to note: 1. I'll be adding filters as I can. When they get commited, and if you're using the UDO version, it might be best to stop using the UDO version. 2. For zdf_ladder, I've adjusted the resonance mapping as I think I had gotten it wrong earlier. The resonance range is still 0 to 1.0, but this now maps to Q range of 0.5 to 25.0. The previous calculations were off and could allow fairly catastrophic values as resonance was getting closer and closer to 1.0. As it is now, it will get to 25.0 which self-oscillates and stop there. 3. I'm not 100% that the resonance mapping to Q is so great in terms of its curve. I'm using Q = 1 / (2 * (1 - adjustedRes)). (adjustedRes goes from 0-0.98). It makes it hard to notice resonance changes until it gets closer to 0.95 or so. If anyone has suggestions here, it'd be very much appreciated. 4. My plan is to add the filters, then work on documentation and examples at end. If there's anyone using develop branch, any tests/feedback on the filters is always appreciated. Thanks!

Date	2017-04-04 19:58
From	Anton Kholomiov
Subject	Re: FYI: ZDF Filters
	Great news! thanks for your effort Steven! 04 апр. 2017 г. 19:43 пользователь "Steven Yi" <stevenyi@gmail.com> написал: Hi All, Just FYI, now that it's easy for me to develop with Visual Studio, I'm starting work on translating those zero-delay feedback filters (the ones by Will Pirkle that I had done UDO versions) to C in Csound. I've just pushed the first commit which has the zdf_ladder. A couple things to note: 1. I'll be adding filters as I can. When they get commited, and if you're using the UDO version, it might be best to stop using the UDO version. 2. For zdf_ladder, I've adjusted the resonance mapping as I think I had gotten it wrong earlier. The resonance range is still 0 to 1.0, but this now maps to Q range of 0.5 to 25.0. The previous calculations were off and could allow fairly catastrophic values as resonance was getting closer and closer to 1.0. As it is now, it will get to 25.0 which self-oscillates and stop there. 3. I'm not 100% that the resonance mapping to Q is so great in terms of its curve. I'm using Q = 1 / (2 * (1 - adjustedRes)). (adjustedRes goes from 0-0.98). It makes it hard to notice resonance changes until it gets closer to 0.95 or so. If anyone has suggestions here, it'd be very much appreciated. 4. My plan is to add the filters, then work on documentation and examples at end. If there's anyone using develop branch, any tests/feedback on the filters is always appreciated. Thanks! steven 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

Date	2017-04-04 20:50
From	"Dr. Richard Boulanger"
Subject	Re: FYI: ZDF Filters
	This will be awesome. We might be able to test them here at Berklee. - it would be nice to feature them at MoogFest! -dB _____________________________________________ Dr. Richard Boulanger Professor of Electronic Production and Design Professional Writing and Music Technology Division Berklee College of Music ______________________________________________ President of Boulanger Labs - http://boulangerlabs.com Author & Editor of The Csound Book - http://mitpress.mit.edu/books/csound-book Author & Editor of The Audio Programming Book - http://mitpress.mit.edu/books/audio-programming-book ______________________________________________ about: http://www.boulangerlabs.com/about/richardboulanger/ about: http://www.csounds.com/community/developers/dr-richard-boulanger/ music: http://www.csounds.com/community/developers/dr-richard-boulanger/dr-richard-boulanger-music/ ______________________________________________ email: rboulanger@berklee.edu facebook: https://www.facebook.com/richard.boulanger.58 On Tue, Apr 4, 2017 at 2:58 PM, Anton Kholomiov <anton.kholomiov@gmail.com> wrote: Great news! thanks for your effort Steven! 04 апр. 2017 г. 19:43 пользователь "Steven Yi" <stevenyi@gmail.com> написал: Hi All, Just FYI, now that it's easy for me to develop with Visual Studio, I'm starting work on translating those zero-delay feedback filters (the ones by Will Pirkle that I had done UDO versions) to C in Csound. I've just pushed the first commit which has the zdf_ladder. A couple things to note: 1. I'll be adding filters as I can. When they get commited, and if you're using the UDO version, it might be best to stop using the UDO version. 2. For zdf_ladder, I've adjusted the resonance mapping as I think I had gotten it wrong earlier. The resonance range is still 0 to 1.0, but this now maps to Q range of 0.5 to 25.0. The previous calculations were off and could allow fairly catastrophic values as resonance was getting closer and closer to 1.0. As it is now, it will get to 25.0 which self-oscillates and stop there. 3. I'm not 100% that the resonance mapping to Q is so great in terms of its curve. I'm using Q = 1 / (2 * (1 - adjustedRes)). (adjustedRes goes from 0-0.98). It makes it hard to notice resonance changes until it gets closer to 0.95 or so. If anyone has suggestions here, it'd be very much appreciated. 4. My plan is to add the filters, then work on documentation and examples at end. If there's anyone using develop branch, any tests/feedback on the filters is always appreciated. Thanks! steven 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 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

Date	2017-04-04 20:57
From	Hlöðver Sigurðsson
Subject	Re: FYI: ZDF Filters
	yummy, thanks a lot for this Steven! 2017-04-04 21:50 GMT+02:00 Dr. Richard Boulanger <rboulanger@berklee.edu>: This will be awesome. We might be able to test them here at Berklee. - it would be nice to feature them at MoogFest! -dB _____________________________________________ Dr. Richard Boulanger Professor of Electronic Production and Design Professional Writing and Music Technology Division Berklee College of Music ______________________________________________ President of Boulanger Labs - http://boulangerlabs.com Author & Editor of The Csound Book - http://mitpress.mit.edu/books/csound-book Author & Editor of The Audio Programming Book - http://mitpress.mit.edu/books/audio-programming-book ______________________________________________ about: http://www.boulangerlabs.com/about/richardboulanger/ about: http://www.csounds.com/community/developers/dr-richard-boulanger/ music: http://www.csounds.com/community/developers/dr-richard-boulanger/dr-richard-boulanger-music/ ______________________________________________ email: rboulanger@berklee.edu facebook: https://www.facebook.com/richard.boulanger.58 On Tue, Apr 4, 2017 at 2:58 PM, Anton Kholomiov <anton.kholomiov@gmail.com> wrote: Great news! thanks for your effort Steven! 04 апр. 2017 г. 19:43 пользователь "Steven Yi" <stevenyi@gmail.com> написал: Hi All, Just FYI, now that it's easy for me to develop with Visual Studio, I'm starting work on translating those zero-delay feedback filters (the ones by Will Pirkle that I had done UDO versions) to C in Csound. I've just pushed the first commit which has the zdf_ladder. A couple things to note: 1. I'll be adding filters as I can. When they get commited, and if you're using the UDO version, it might be best to stop using the UDO version. 2. For zdf_ladder, I've adjusted the resonance mapping as I think I had gotten it wrong earlier. The resonance range is still 0 to 1.0, but this now maps to Q range of 0.5 to 25.0. The previous calculations were off and could allow fairly catastrophic values as resonance was getting closer and closer to 1.0. As it is now, it will get to 25.0 which self-oscillates and stop there. 3. I'm not 100% that the resonance mapping to Q is so great in terms of its curve. I'm using Q = 1 / (2 * (1 - adjustedRes)). (adjustedRes goes from 0-0.98). It makes it hard to notice resonance changes until it gets closer to 0.95 or so. If anyone has suggestions here, it'd be very much appreciated. 4. My plan is to add the filters, then work on documentation and examples at end. If there's anyone using develop branch, any tests/feedback on the filters is always appreciated. Thanks! steven 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 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