Suggestion on audio -> additive synth


    Mar 12 2010 | 7:59 pm
    Hi All,
    I need to do something that's probably not that difficult, but I haven't done a ton of MSP, so I'm not sure the best way to go about doing it. I need to grab a short chunk of live audio, then resythnesize it using some sort of additive synthesis. The point is to transition from the live sound down to just a few sine waves, over some variable period of time (and to have sines "die off" at different rates). I'd thought to use a phase vocoder "freeze" type of approach, then filter the frozen audio down to individual sines. If this seems like a reasonable approach, I could use a few tips on the filtering approach. I want to be able to specify the sines that remain, so I'd ideally want something like that could be controlled by a multislider, or similar interface. The other thought was to somehow produce an SDIF model, then use the CNMAT objects to do the synthesis. But I'm not sure how you get from a sampling of live audio (just a few frames would do) to an SDIF model...
    Any other thoughts on better ways to accomplish what I'm after would also be appreciated.
    thanks,
    J.

    • Mar 12 2010 | 10:17 pm
      Hi there!
      What you describe, could be done like so:
      -Grab a copy of the patches from the phase vocoder tutorial from c. lippe, it is here on the site! -Grab a copy of the main pfft patch of forbidden planet example (on your max folder. -Hook the output of the phase vocoder patch to the input of the forbidden planet patch, use multislider to control the latter. -Quick AND dirty!@ :)
      Cheers, Panos
      PS: well, DO "save as" ;P
    • Mar 12 2010 | 11:17 pm
      Ha, nice! I had actually already pillaged the phase vocoder tutorial, and made my live audio "freeze" patch. But thanks for the tip on forbidden planet! That absolutely does the trick! Just have to automate the filtering and I'm well underway.
      cheers,
      J.
    • Mar 13 2010 | 10:22 am
      kind of OT, but is the c.lippe pvoc toot Mac only? I downloaded the zip and the articles, but the patches won't open in Max5; they appear as wordpad files, and copy/paste doesn't work either
    • Mar 13 2010 | 11:16 am
      @brendan: no afaik, BUT it might be a .pat file (older max format). Max 5 opens it, no prob. Try opening the file from inside max, not by clicking on it.
    • Mar 13 2010 | 3:36 pm
      so easy to miss the obvious sometimes - thanks, sorted
    • Mar 15 2010 | 5:48 pm
      It has a lot of related things that do exactly what you are looking for.