[based on/from the JV-1080 Owners Manual, pages 81-82]
[not available in the XP-50 (-80?) Owners Manual]
[but HIGHLY desirable!!!]

Using Effects
=============
The routing of the JV-1080's effects will depend on the
settings of each Tone and on the effect output assign and
level settings.

For each routing, you may think of a level setting of 0 as
being disconnected, as a level setting of 1-127 as being
connected. Effect routing is determined by the various level
settings and output assign settings. The following diagrams
[below listed table] are example settings in Patch mode which
you may use as guidelines for you effect settings. The output
assign and level settings shown at the left of each diagram
[converted into a table below] will result in the effect
routing shown in the diagrams at right [below listed table].
Parameter values listed as 1-127 can be set to any desired
value.

* Parameters listed as "--" will be ignored even if you set
  a value.
* Only the sound to which the effect has been applied will be
  output with chorus and reverb, while EFX contains the
  original sound as well.

[1] Output the unprocessed sound from MIX OUT
---------------------------------------------

[2] Use chorus and reverb in series
-----------------------------------

[3] Use only EFX
----------------

[4] Apply reverb only to the chorused sound and use in
parallel with EFX
------------------------------------------------------

[5] Use EFX, chorus and reverb in series
----------------------------------------

[6] Use chorus and reverb in parallel, and EFX in series
--------------------------------------------------------

[7] Use EFX, chorus and reverb in parallel
------------------------------------------

[8] Simultaneously use both parallel and series
-----------------------------------------------

1 OUTPUT
A  Output Assign
B  Output Level
C  Chorus Send Level
D  Reverb Send Level
2 PATCH EFX OUT
A  Output Assign
B  Output Level
C  Chorus Send Level
D  Reverb Send Level
3 PATCH CHORUS
A  Chorus Level
B  Chorus Output Assign  
4 PATCH REVERB
A  Reverb Level

  [1]    [2]     [3]     [4]     [5]     [6]     [7]     [8]
1 OUTPUT -------+-------+-------+-------+-------+-------+-------
A MIX   |MIX    |EFX    |EFX    |EFX    |EFX    |EFX    |EFX
B 1-127 |1-127  |1-127  |1-127  |1-127  |1-127  |1-127  |1-127
C 0     |1-127  |0      |1-127  |0      |0      |1-127  |1-127
D 0     |1-127  |0      |0      |0      |0      |1-127  |1-127
2 PATCH EFX OUT +-------+-------+-------+-------+-------+-------
A --    |--     |MIX    |MIX    |MIX    |MIX    |MIX    |MIX
B --    |--     |1-127  |1-127  |1-127  |1-127  |1-127  |1-127
C --    |--     |0      |0      |1-127  |1-127  |0      |1-127
D --    |--     |0      |0      |1-127  |1-127  |0      |1-127
3 PATCH CHORUS -+-------+-------+-------+-------+-------+-------
A --    |1-127  |--     |1-127  |1-127  |1-127  |1-127  |1-127
B --    |MIX+REV|--     |REV    |MIX+REV|MIX    |MIX    |MIX+REV
4 PATCH REVERB -+-------+-------+-------+-------+-------+-------
A --    |1-127  |--     |1-127  |1-127  |1-127  |1-127  |1-127
----------------------------------------------------------------

The examples here use one Tone from the Patch mode. Since the
Output Level, Chorus Send Level, and Reverb Send Level can be
set independently for each Tone, you make whatever settings
you need for each one when using multiple Tones. Individual
settings for the Tone level are basically ignored when in
Performance mode--the level is controlled by the settings for
output made for each Part. (It may be helpful to substitute
PART for TONE when viewing the illustrations [i.e. the table
above].)

Only when Out[ut Assign is set to "Patch" will the balance for
level of individual Tones set for Patches be reflected in the
Parts. Note also that if a different EFX type is set for Patches
and Performances, unexpected effects could be obtained from
Parts. To avoid this, you can either set Output Assign to MIX,
or use only Patches which are spefically set for the way that
the Performance is to be used.