Our ProV-Midifiles (GM, GS, XG and XF and also Tyros and Korg-PA adaptations) include an arranged vocalist track on channel 16.
This means: You use this track for triggering a Vocalist (internally in the keyboard and external) and thus generate the correct vocal harmonies (2nd voice, 3rd voice, etc.).
In case of Yamaha devices the VH-Preset "Vocoder XG" is loaded by a System Exclusive (SysEx) command, the VH channel is set to 16 and Vocal Harmony is activated (you'll se that as the LED on the VH switch is on).
When singing the correct harmonies are produced now at the correct locations automatically.
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