A ProV-Midifile is distinguished mainly by the fact that a Arranged Vocalist Track (AVH) is integrated on Channel 16, which contains the vocals harmonies (VH). This is what the "V" means. Otherwise, it corresponds to the sound formats and adaptations of a Pro-Midifile.
Adaptations are treated during purchase process like a sound format.
Unlisted Midi-channels are used as needed.
Of course, channels are not or differently used, if the original (the original song) should not require a corresponding assignment.
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