TouchOSC and/or Lemur + Audulus oddities
  • Hey there,

    I just purchased Audulus and was very excited about Audulus features and capabilities.
    The first thing I went to create was a harmonic oscillator (a sound source which consists of several (in my case 8) oscillators, each of which putting out an xth (1*, 2*, 3*, 4* etc, also known as the harmonic frequencies) of the original frequency.

    That means I have:
    1x constant (main frequency value) going to
    8x math mult (1*, 2*, 3*, 4* etc) each going one of:
    8x sine oscs each going to one of:
    8x level

    First four oscs go into one 4x1 mixer the other half to another 4x1 mixer.
    Both of these going to one crossfade and then to two outputs.

    If I now activate Learn MIDI CC for each of the 8 levels and change to Lemur (or TouchOSC for that matter), I hear the control (in this case a fader for each of the 8 levels in Audulus) working until Audulus starts to behave erratic until finally there is no sound coming from Audulus anymore. When I now switch back to Audulus, it starts to process the queued fader movements that I did in Lemur (or TouchOSC). Often it ceases to respond to Lemur at all, even if I was only controlling one of the 8 levels of the oscillators from Audulus from within Lemur or TouchOSC.

    The patch in Audulus shows 4% CPU usage.
    I'm using a iPad Mini Retina display (iPad Mini 2) with the 64bit 1.3GHz A7 chip running iOS8.1. MIDI is routed from Lemur or TouchOSC to Audulus via the according option in Lemur or TouchOSC respectively. No other apps are running in the background (no audio applications or effects or something along those lines).
    Could it be that the iPad Mini is too weak to run Audulus, is this a bug within Audulus or am I doing something wrong?

  • @dualmono, sorry about that! I bet it is a bug. Let me do some testing with Lemur (I have it) and I'll get back to you. Oh, and could you email me your patch?

    - Taylor
  • Hey there,
    I just sent an email to support(a) and attached the patch.
    I hope that was the correct address.

  • Same thing happens to me with MIDI Designer Pro, for what it's worth.
  • @dualmono, @jjthrash. I've looked at the code a bit and I see the problem. Looks like a bug I introduced in the last version when trying to simplify some code. Sorry about that!

    Basically, when the app goes into the background it stops sending MIDI CCs to knobs. I'm going to have to think about the best way to fix this, it might be a bit tricky.
  • @dualmono, @jjthrash, ok fixed it! The fix will be in the next release.
  • Thats great! Looking forward to it.
    By the way, what is the recommended max of cpu usage on the iPad Mini2 for Audulus and background application?
    Is 4% a lot? Just trying to put it into perspective.

  • @Taylor, that's great! I love that I can build instruments in Audulus, and interfaces in MIDI Designer. It's a good abstraction.

    @dualmono, 4% is pretty typical for straightforward patches on my iPad 4, which is one generation behind the iPad Mini 2. Throw in feedback loops, reverb, or something