High CPU with Thunderbolt Clarett interface

    Apr 02 2019 | 8:14 am
    Hello I am running a big patch for ambisonics reproduction and I just bought a focusrite clarett 8prex interface with thunderbolt connnection.
    the patch runs some vst and the hoa library for ambisonics
    i have used this with an RME fire face 400 with a max of 60% cpu and with RME madiface with max 50% cpu
    with the clarett I have 100% cpu
    my vector size and buffer are at 512 in all cases
    my laptop is MacBook Pro 15” early 2011 16Gb ram thinderbolt 1
    i use max 7
    if I run an intensive ambisonics project in reaper with the same vst and some more I have 5% cpu with 16 channels
    Is it possible max 7 does not work well with this interface or any thunderbolt? cannot find anything on the forum

    • Apr 02 2019 | 9:13 am
      the difference between max and reaper is the VST (effect, i.e. audio in and out) plug-ins. but if the vector size is really 512 you should not see a difference between interfaces. (100% instead of 50% sounds a bit like the vectorsize would be 4 instead of 32...)
    • Apr 02 2019 | 9:21 am
      Thanks for the response
      vector size is 512 as well.
    • Apr 05 2019 | 7:41 pm
      i'm running with a Clarett 4Pre on macbook pro (Mid 2015), 2.8 GHz i7, 16 GB ram, MacOSX 10.14.4(Mojave) and Max8 (i remember same system back when i was on Max7 worked fine, too) same audio-status settings(vs 512) but with "Scheduler In Overdrive" and "Audio Interrupt" both checked.
      no probs here(CPU in audio-status drops a little when using it as compared to built-in output, so that's also nice), either it's specifically about the 8Pre(but i think we use the same drivers), or maybe thunderbolt version(i'm on thunderbolt 2(?)), or perhaps could be something to do with your VSTs(?)