Le 8 août 08 à 14:46, Julian Brooks a écrit : > Hi Jack, > > Well I was surprised that someone else hadn't tried it already, to be > honest. > > Congratulations, respect, and thanks for showing me that it is indeed > possible. > > If you don't mind I would like to be able to email you with > problems that I > think you can help/give advise for. I think the better way is to post on the Pd list because i'm not always available to answer (lot of work sometimes) and a lot of people are good users of this programming language. The list exists for this sort of problem ;) You have a lot of time to realize your patch, i think after 12 months you will have a good patch for your wind chime. All you need is to know PD/GEM/PMPD. I will be happy to help you and to answer to you on the list like a lot of other people. ++
Jack > > Best wishes, > > Jb > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of > Jack > Sent: 08 August 2008 12:38 > To: cyrille henry > Cc: [email protected]; Mark Sexton > Subject: Re: [PD] physical modelling/general pd > > Hello Julian, > I have done a wind chime there is 2-3 years ago with PD/GEM/PMPD. I > used PHP to get on the web the value of direction and force of wind > in differents cities in Europe. > Here a link for a video without sound (i remove it from the export) : > http://djrayban2.free.fr/Movie/windChime.mov > ++ > > Jack > > Le 8 août 08 à 12:16, cyrille henry a écrit : > >> hello, >> >> >> Mark Sexton a écrit : >>> Hi Julian >>> Building a physical model of a wind chime might be easier than you >>> think, if >>> you use modal or banded waveguide approaches to physical modelling >>> rather >>> than the brute force approach of pmpd. >> >> pmpd aim to model the movement, not the sound. >> the hamer and the tube of a simple wind chime could be modeled with >> about 10 masses. >> To create a physical model of the sound is very different. >> but you need both to model the wind chime. >> >> Cyrille >> >> >> >> >> >> >> >>> >>> If you think of the wind chimes should as stiff bars, banded >>> waveguides >>> would be ideal and are much more computationally efficient to >>> implement than >>> brute force approaches: a resonant filter and delay per mode you >>> want to >>> synthesis. I'd recommend perhaps starting with a simple modal >>> implementation using filters and build up from there. This paper >>> gives a >>> good introduction: >>> http://www.cs.ubc.ca/~kvdoel/publications/modalpaper.pdf >>> >>> >>> If you're not familiar with modal synthesis and banded waveguides >>> there's >>> plenty of information online and Perry Cook's book gives a good >>> overview of >>> a range of approaches to modelling. >>> http://www.cs.princeton.edu/~prc/AKPetersBook.htm >>> >>> Some starting hints if you want to go down this route: >>> >>> 1. Create an impulse: a buffer of noise or single sample impulse >>> 2. Feed this into perhaps 5 band pass IIR filters with a very >>> narrow Q, >>> these will provide your resonant modes for each chime. >>> 3. The frequencies of these filters will probably be non-integer >>> multiples >>> of the fundamental, eventually you can get these by analysing an >>> actual wind >>> chime, but if you wanted to build a proof of concept now then >>> these are >>> typical modes of an aluminium bar (you can find further modal >>> frequency >>> ratios in the Csound manual): >>> [1, 2.756, 5.423, 8.988, 13.448, 18.680] >>> 4. Scale the outputs of each of the resonant filters as >>> appropriate, this >>> should be straight forward once you've done an audio analysis of >>> your wind >>> chime. >>> >>> At this point you have a simple resonating model of a wind chime. >>> >>> 5. Perhaps replace the impulse: you can remove the resonant >>> components of >>> your wind chime recording and this will leave you with the >>> original noise >>> impulse. Using this to trigger your model should help improve >>> realism. >>> 6. Create a banded waveguide version, by adding feedback delays >>> for each >>> mode. (have a read of this paper and a look at Fig. 4): >>> http://soundlab.cs.princeton.edu/publications/1999_icmc_bar.pdf >>> >>> There's a few further tweaks and improvements that can be done, but >>> something along these lines should give a good result, be fairly >>> easy to >>> implement and run more efficiently than brute force. >>> >>> Happy to chat more on or off list on the physical model side or >>> algorithmic >>> composition side, but you may find it easier than you thought once >>> you get >>> going. >>> >>> >>> All the best >>> >>> Mark Sexton >>> Senior Lecturer >>> MSc Computational Sound >>> University of Portsmouth >>> >>>> Message: 2 >>>> Date: Thu, 7 Aug 2008 12:30:51 +0100 >>>> From: "Julian Brooks" <[EMAIL PROTECTED]> >>>> Subject: [PD] physical modelling/general pd - mentor/tuition sought >>>> (money offered) >>>> To: <[email protected]> >>>> Message-ID: <[EMAIL PROTECTED]@virgin.net> >>>> Content-Type: text/plain; charset="us-ascii" >>>> >>>> Hi all, >>>> >>>> >>>> >>>> I have a 12 month project as part of a masters degree, where I >>>> wish to build >>>> a physical model of a wind chime. I then want to use the >>>> interface to play >>>> some of my indeterminate compositions. I was going to attempt it >>>> for my >>>> undergraduate degree but realised that it was far too complex for >>>> the >>>> available time that I had then. >>>> >>>> >>>> >>>> I have been using pd for a few years now, list lurking, working >>>> through >>>> basic examples, building simple tools, using other peoples >>>> patches etc. But >>>> this is too complex for me to do on my own. At my uni there >>>> isn't anyone >>>> with better skills than me and I don't know of any local fellow >>>> patchers. >>>> >>>> >>>> >>>> Now as a musician, when I need to up my skills, I will look to >>>> find some >>>> lessons when I have got as far as I can on my own. >>>> >>>> >>>> >>>> So here goes... >>>> >>>> >>>> >>>> Is there anyone with an hour a week to spare who can offer some >>>> mentoring/tuition for what we can deem to be the 'going rate'. I >>>> am more >>>> than happy to do this remotely/online, I'm sure there is a way we >>>> can work >>>> it out. There would be full credit given of course. >>>> >>>> >>>> >>>> Pmpd seems like the way to go with this. I have worked through the >>>> examples, and, although I have my eye on what examples I would >>>> presume to be >>>> the best starting points, I'm struggling to get started. The >>>> physical >>>> modelling is where I first need to start but there's loads of pd >>>> stuff I >>>> would like to be able to work through with someone, so this could >>>> be a (me >>>> love you)longtime regular small money earner, if anyone's >>>> interested. >>>> >>>> >>>> >>>> I am in Hebden Bridge, West Yorkshire, UK, by the way. Any >>>> pd'ers local, >>>> give us a shout. >>>> >>>> >>>> >>>> Best wishes to all, >>>> >>>> >>>> >>>> Jb >>>> >>> >>> >>> >>> _______________________________________________ >>> [email protected] mailing list >>> UNSUBSCRIBE and account-management -> http://lists.puredata.info/ >>> listinfo/pd-list >>> >>> >> >> _______________________________________________ >> [email protected] mailing list >> UNSUBSCRIBE and account-management -> http://lists.puredata.info/ >> listinfo/pd-list > > > _______________________________________________ > [email protected] mailing list > UNSUBSCRIBE and account-management -> > http://lists.puredata.info/listinfo/pd-list > _______________________________________________ [email protected] mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
