Dynamically changing Delay Line


    Jul 28 2010 | 9:09 pm
    Hello,
    Does anyone know how to create a dynamically changing delay line using tap in tap out where it doesn't distort the audio too much. I am trying to create continuous non-linearity in the string. Excuse me if I don't have the terminology correct.
    Cheers,
    Dave

    • Jul 28 2010 | 9:27 pm
      Are you modulating the delay line at audio rate? That's the first step. The second would be to smooth the changes in the modulating signal with onepole~/slide~/rampsmooth~ etc... if necessary. This depends on how you're modulating though, if you're using an lfo (cycle~/phasor~ etc...) then a smoothing filter won't be necessary.
      I'm not well-versed in physical string modelling (sounds like what you're doing), so I can't offer much advice on exactly how to go about achieving the non-linearity that you want.
    • Jul 28 2010 | 9:40 pm
      Nice one Tim. I'll give that a try. What I have tried to do is modulate the delay length of a Karplus strong with a another Karplus Strong so that it kind of fades out and eventually stops changing the delay length but it's still a bit glitchy. Cheers anyway!
    • Jul 28 2010 | 11:26 pm
      I'm afraid modulating the delay line with the audio rate distorts it even more.I'm going to have to figure something else out. Thanks for your help anyway.
    • Jul 28 2010 | 11:50 pm
      Could you post an example? You should be able to modulate tapout~ at audio rate with no glitches/distortions. Maybe you're modulating so fast you're creating FM sidebands, hard to say without seeing a patch.
    • Jul 29 2010 | 9:04 am
      tim is right as usual. in the meantime, the poletti m4l example is sitting in your patches folder and works great: Max5/patches/m4l-patches/Tools resources/M4L.vdelay~.maxpat
    • Jul 29 2010 | 1:17 pm
      Nice one guys. The patch I have attached is part of a bigger patch. I'm trying to physically model a sitar as part of my masters thesis. All the main inner workings of my model are contained in the patch I have attached.
    • Jul 29 2010 | 1:20 pm
      Actually might as well include the whole thing for clarity. At the moment I have it set to modulate the tapin tap out with not using the audio rate. Everything is in the string1 subpatch
    • Jul 29 2010 | 1:53 pm
      I made some tiny changes that seem to have stopped the distortion, but I may be missing something; it's a big patch! The bits I changed are outlined in red.
    • Jul 29 2010 | 3:41 pm
      That's perfect Tim!! Thank you so much, you've saved me many a panic attack. My thesis is due in a few weeks.
    • Sep 08 2010 | 9:45 pm
      interested to hear the final thing did you do more to it?
      oli
    • Sep 15 2010 | 4:31 pm
      I have indeed, submitted my thesis last week. Please find attached and enjoy.
    • Sep 15 2010 | 6:06 pm
      impressive!
    • Sep 15 2010 | 6:58 pm
      great stuff.
      you forgot to include the "sitar.mid" file?...
    • Sep 15 2010 | 7:01 pm
      It's not worth listening to really, very simple demo of its sound. Although, I did do a composition using it. Its not very obvious I used it though because of all the time stretching. http://soundcloud.com/davidronan
      It's called "Called Anon Tiro"
    • Sep 15 2010 | 7:02 pm
      really good work, thanks for posting. Will you make the thesis available too?
      it's a shame that the tuning is compromised in the higher registers. A bit better with sigvs @ 4, but then the cpu goes through the roof.
      oli
    • Sep 15 2010 | 7:26 pm
      I will indeed, I still have a week to make a few changes to the writing, I'll post it when it is finished.
      Ya the thing eats cpu big time, it's a pity.