ES-8 - Keyboard Node Hz to 1v/oct
  • Don't know if this has been mentioned here yet.

    (log2(Hz/32.702))/10

    Add this expression to a EXP node and it let's you use the KEYBOARD node Hz straight out of an ES-8 into a 1V/OCT input on modules with no OSC node required within Audulus. This covers notes from C1 to C9 using the Keyboard node

    Thought about this while putting together a smaller travelling eurorack case.
  • Very cool! I am curious how you derived the 32.702 constant. Also, I have found that I usually better off clamping the output of the midi keyboard Hz output, clamp(hz,20,48000) or something, to avoid having log2(0) when you open the patch. If you are getting white cables, that might be why.
  • @RobertSyrett 32.702 is the lowest Hz the Keyboard node produces.

    I just emptied my bin and my working was in there. But I think I was working off the standard frequency equation

    fn = f0 * (a)^n

    and just solved for n.

  • Hey Johnson thanks for this! Are you finding that the tuning stability works well for this? In the past we've derived VPO from the Octave signal in Audulus, but doing it this way might be more accurate for some reason?
  • I think the primary benefit is that the expression is immediate, and requires no further explanation.
  • @RobertSyrett - weren't you saying the way we were doing VPO conversion was having tuning stability issues across large octaves? I haven't dove into testing it much myself yet, I know that in A4 we'll have a Silent Way type sampler/compensator that will be able to force the VPO output to be more in tune (and even compensate for oscillator drift as well)
  • @biminiroad When I compare it to the midi to CV conversions of the MI yarns, yes there is some tuning stability issues, but I think they are within acceptable ranges for everyday use. If you really need to use one oscillator over several octaves the way to go is just generate the signal within audulus (where the tuning is as perfect as your sample rate) and send it to be processed in the modular. Audulus sounds pretty good after all.
  • word good to know!