On Thu, Apr 6, 2017 at 11:28 AM, Mark Conway Wirt <[email protected]> wrote: > I was wondering if you can produce realistic sounds by literally solving the > string equation for an electric guitar... > > > Perhaps, but you would probably have issues with performance -- you may be > able to get a good sound, but it would be difficult to generate it in real- > or near-real time.
Yes, I am not interested in real time. I am interested in solving the actual physics, with good numerics (e.g. convergence, verification, etc.) and getting good sound. So if it takes 1h to get 1s of sound, that's totally fine with me. My suspicion is that you might be able to get better sound with the approaches below (since they fine tune the parameters and make it sound good), than with a direct solve of the physical equation (without artificially fine tunning any parameters), but perhaps not. So that's why I am curious. > > For strings (and some kinds of percussion) physical modeling is often used, > but not taken in the direction of modeling the string or membrane. The most > common form of modeling is digital waveguide synthesis. One of the earliest > "good sounding" approaches was probably the Karplus-Strong algorithm, which > is usually considered a physical model (albeit a pretty abstract/conceptual > one). Yes, that is an example of what I meant by the "shortcut" approach, as it seems to be just some digital filters, but not really solving a physical equation (https://en.wikipedia.org/wiki/Karplus%E2%80%93Strong_string_synthesis), at least not directly. But since it sounds nice, it must be doing something right, but it feels like they skipped the actual physical model, and just created an algorithm, but I can't see how this directly corresponds to a vibrating string. > > You may want to look at cSound's repluck (which is based on Karplus-Strong). > > http://www.csounds.com/manual/html/repluck.html Nice, thanks, it took me a while to find the actual source code: https://github.com/csound/csound/blob/6d8779dc884f79d6aa43a21f163e36bc67c3c411/Opcodes/repluck.c It seems both this code, as well as Karplus-Strong, is not really solving the physical equation, it's just a good sounding model. Ondrej > > On Thursday, April 6, 2017 at 12:55:06 PM UTC-4, Ondřej Čertík wrote: > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/sympy. > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/df2cf836-1512-443f-b9c4-f7a69cec3e6f%40googlegroups.com. > > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CADDwiVCN80-jj%3Dfk3cr_2%2B1KLh2HMwgGBDiYr9%3D8bVtJHjYaHA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
