Roland SUPER JX-10 Owner's Manual page 77

[61
UPPER
MIDI
CH SEND]
[62
LOWER
MIDI
CHSEND],
Transmitting MIDI
CH
UPPER
LOWER
OFF
3
2
4
OFF
4
1
OFF
1
3
2
4
2
4
1
2
In
this
way, changing
Patch
Memories
selects
two
of
the MIDI
Sound Modules
to
be used.