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When sustaining, sound drops.

547 Views 8 Replies Latest reply: Feb 10, 2013 2:10 AM by Phij RSS
NENA 77 Level 1 Level 1 (60 points)
Currently Being Moderated
Jul 30, 2012 8:26 PM

I'm just starting to use Mainstage 2.1.3  Op 10.6.8

Unfortunatly I don't have the money for a brand new usb controller. So at the moment I'm using a Roland XV-88 via midi.

Doing a gig, all's going well, and then about 40 minutes in, I'm noticing, while holding a string sound for about ten seconds, it chops off as if the lap top was instantly turned off even though it's still on. At the end of the set, I restart, and were back to normal. Now the next set it doen't happen, or maybe it does, who knows?

Could this be due to some eroneous midi info being spit out by the XV-88, or some tweaking needs to be done in Mainstage? Thanks.

MacBook, Mac OS X (10.6.8)
  • gen_ Level 2 Level 2 (335 points)
    Currently Being Moderated
    Jul 31, 2012 3:46 AM (in response to NENA 77)

    This is caused by one of two things. Assuming you are using EXS24 to play instruments then you may simply have run out of polyphony. EXS and all other samplers set a maximum amount of samples to be played and cut off the first sample pressed when you press any notes that exeed that. On most presets your Polyphoney is set to 32 voices (samples) but most piano samples will have more than one voice per note played. Try increasing your poyphony in the EXS instrument view.


    The other issue could be that you simply ran out of streaming bandwidth on your hard drive when you were playing. If you've already increased your polyphony, or are using big patch (bigger than the ones Logic came with) you could have reached the point where you're playing so many notes that your harddrive can't keep up. In this case you would hear the start of the note and then it would apbruptly cease. This is becasue all notes on the instrument have thier first half second loaded into memory so the hard drive has enough time to find the sample file and continue playing it, but if the hard drive is busy finding and playing a lot of other soudns then it will fail to find the new one it time and hte sound will be canceled. In this case you will probably need to buy a faster external harddrive and run the samples from that. I cannot give you a guide as to what your options are but any desktop sized external 3.5" hard drive (which is larger in physical size and needs to be plugged into a wall) should be fine as they have superior speeds to your built in 5400 and 7200rpm Mac drives.

  • gen_ Level 2 Level 2 (335 points)
    Currently Being Moderated
    Jul 31, 2012 4:32 AM (in response to gen_)

    Just to clarify, polyphony is raised by increasing the number in the little black box next to the word 'voices'. It's he top corner number displaying 64 in this image.

    Screen Shot 2012-07-31 at 12.31.29.png

  • gen_ Level 2 Level 2 (335 points)
    Currently Being Moderated
    Jul 31, 2012 5:52 AM (in response to NENA 77)

    Sounds odd, well if the problem comes back, let us know. There are a few diagnostics that can be run to see if everything is A-OK on your system.

  • gen_ Level 2 Level 2 (335 points)
    Currently Being Moderated
    Jul 31, 2012 11:36 PM (in response to NENA 77)

    Well the first thing you can try is a MIDI test, this will tell you if any of you devices are conflicting or sending malformed signals. The instructions are here


    The second thing you can do is look in logic for a Stop CC being triggered, this is a MIDI command that instantly stops all audio signal. Logic usually sends it to all instruments when you stop playing a song (I.E hit the spacebar). If you're playing from slightly older tech (especially synths with keyboards attached), or have MIDI playthrough on your new keyboard, they cpuld be sending thier own at random times and this may be the issue. Look for CC control signals 120-127 popping up in the bar, and go into Preferences > MIDI > general and make sure External Stop Message Ends recording is ticked. Then reset drivers and check in the box next to CPU use on the transport to see if any reset messages arrive. These would have different names on the top portion of the box, but always have x, (a number between 121 and 126), x. With X being an unimportant number.


    Finally, it could be CoreAudio at fault. As much as I love CoreAudio when it does work, when it doesn't its a *****. If it comes to that we'll delete caches, preferences and try as much as we can, but you may have to reinstall to fix it.

  • gen_ Level 2 Level 2 (335 points)
    Currently Being Moderated
    Jul 31, 2012 11:39 PM (in response to gen_)

    And to add, you're looking for the MIDI test to flash at the point when your audio drops, or shortly before. Try it on its own, and see if it lights up randomly at first.

  • Phij Calculating status...
    Currently Being Moderated
    Feb 10, 2013 2:10 AM (in response to NENA 77)

    Hi- this a known bug and there is a thread on it here....



    Soeoe claims that 2.2 helps the problem but I can't confirm this.


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