Warning ... extreme novice is
writing the following ...
Continuing from the Subject of the post:
However, a downloaded midi file import has a brief 2 bars where a
"harp" (bank 0, patch 46) (Channel 10) run up instead plays a
variety of the PSR-E333 drum type sounds. Far as I can tell,
however, the other tracks set to different channels use only the
#001 Voice (grand piano)
The "enable MIDI output" section of sf2 play has a "PROGRAM"
setting which I don't know anything about yet. Could that have a
bearing on my confusion?