What’s your goal?
If you’re sending to an audio facility, three separate AIFFs if usually the way to go, if they can’t take an OMF. If they can take an OMF, then that’s what you want to export, plus a self-contained, usually low res, small frame size QT file of the timeline that they can use for reference. (that is usuually requested for either the AIFF or OMF method)
If it’s something else, please tell us what you’re doing, or why you need to get these files out separately. It may help us hel you figure out a workflow for you that’s efficient.
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