Antialiased overdrive~ ?


    Feb 19 2010 | 12:02 am
    Hi,
    i'd like to use overdrive to add harmonics to some melodic sounds, but when you test [overdrive~] with a simple cycle~ you get aliasing (see patch below). it, rather logically, sounds a bit like the "ideal rectangle" from the "rect~.maxhelp" patch.
    Do you see ways to make an antialiased overdrive~ ?
    Thanks in advance.
    Alexandre

    • Feb 20 2010 | 12:28 pm
      no ideas ?
      Is the max community really entirely devoted to aliased sounds esthetics ?
      Thanks a lot
    • Feb 20 2010 | 9:17 pm
      Yeah, aliasing sounds cool. What you could try is stick everything inside a poly~ an upsample everything with a factor two or four. It's all explained in the help file. Use the cross~ object before the out~'s.
      _
      johan
    • Feb 21 2010 | 6:50 pm
      thanks, i'm trying this, but why cross~ instead of lores~ or biquad~ ? is it less expensive ? shouldn't i use also a filter after the [in~] ?
    • Feb 21 2010 | 8:16 pm
      With cross~ this doesn't work because the ramp of the filter is too soft...
      i used vb.cheby~ instead...
      plus i had to filter just after the [in~] because it is not smoothed at all during the upsampling conversion, see patch below (open the poly)...
      this works, and sounds nice but, wow, takes a lot of cpu... i did *8 upsampling but maybe *4 could be enough depanding on the sound.
      also maybe i could find less cpu expensive than vb.cheby~ ?
      I tryed this saturation test also at 96Khz, using 96Khz recordings, (which means upsampling at 8*96=768Khz), this sounds really nice!, it make me remember about my old warm sounding vinyls...
      Bonsoir,
      Alexandre
    • Feb 21 2010 | 8:17 pm
      in the last message :
      Attachments :
      [Denied Mime] upsampled-satu-test.zip (18.5 KB)
      ???
    • Feb 21 2010 | 8:37 pm
      let's try posting each .maxpat separately...
    • Feb 21 2010 | 8:39 pm
      Attachments
      [Denied Mime] vb.cheby~.mxo.zip (11.3 KB)
      [Denied Extension] play1.maxpat (21.6 KB)
      [Denied Extension] satu-upb.maxpat (11.7 KB)
      [Denied Extension] test-satu-upb.maxpat (11.8 KB)
      hm..
    • Feb 25 2010 | 9:11 pm
      finally, attachments working...