The volume of the vocal harmony of PSR740 is not loud enough for the midi sound that I play and sing with. Can anybody tell me on how to adjust the vocal harmony for best effect?

Press the mixer button. The tracks will appear in the display, each with a fader.Select a track with the button beneath it, and use either the +/- buttons or the circular control to reduce the volume.Repeat procedure with the rest of the tracks.

GG