from the JV-1080 Owners Manual, page 80
[not available in the XP-50 (-80?) Owner Manuals]
[but HIGHLY desirable!!!]

Using MIDI Controllers
======================

Controllers and destinations
----------------------------
The JV-1080 allows you to use a variety of MIDI con-
trollers to modify Tone and EFX parameters in real time.
Parameters being controlled are referred to as Destinations,
and you can specify four Destinations in each Tone (up to 16
Destinations for each Patch).
Controllers that are used to control Tone parameters are
referred to as Patch Control Sources. For example if you make
Patch Control Source and Destination settings as shown in the
following diagram, moving the bender lever to left or right (or
up/down if you are using a wheel) will simultaneously con-
trol four Tone parameters: PCH (pitch), CUT (cutoff frequen-
cy), LEV (volume) and PAN (stereo position).

         Patch Control Source
         [==================]
         [     BENDER       ]
         [==================]
                  |
       ------------------------
      |       |       |       |
[===================================]
[     v       v       v       v     ]
[  [=====] [=====] [=====] [=====]  ]
[  [ PCH ] [ CUT ] [ LEV ] [ PAN ]  ]
[  [=====] [=====] [=====] [=====]  ]
[             Destination           ]
[===================================]
                 Tone

For this example, make settings as follows.

(1) Turn on the receive switches for the con-
    trollers you wish to use.
    System parameter / RECEIVE MIDI Page
    Receive Bender: ON

(2) Select the controller you wish to use.
    Patch parameter / CONTROL SOURCE Page
    Patch Control Source 2: BENDER

(3) Set the controller Destination and
    Control Depth.
    Patch parameter / CONTROL 2 Page
    Control Destination 1: PCH
    Control Destination 2: CUT
    Control Destination 3: LEV
    Control Destination 4: PAN
    Control Depth 1: other than 0
    Control Depth 2: other than 0
    Control Depth 3: other than 0
    Control Depth 4: other than 0

The JV-1080 has three Patch Control Sources. Patch
Control Source 1 is fixed at Modulation (control change #01),
but Patch Control Sources 2 and 3 can be freely assigned.

Control EFX parameters
----------------------
To control EFX parameters, use an EFX Control Source. Two
types of controllers can be freely assigned to these EFX
Control Sources as well. The destination will be determined
by the type of EFX that is selected. For example if you select
Overdrive for EFX, the destinations will be set to DRIVE (the
degree of distortion) and PAN (stereo location).

     EFX Control   EFX Control
      Source 1      Source 2
    [==========] [==========]
    [  BENDER  ] [MODULATION]
    [==========] [==========]
         |             |
[===============================]
[        v             v        ]
[     [=====]       [=====]     ]
[     [DRIVE]       [ PAN ]     ]
[     [=====]       [=====]     ]
[          Destination          ]    
[===============================]
          EFX (Overdrive)

To make settings for this example, use the following procedure.

(1) Turn on the receive switch for the controller
    you wish to use.
    System parameter / RECEIVE MIDI Page
    Receive Bender: ON
    Receive Modulation: ON

(2) Select the EFX Type.
    Patch parameter / PATCH EFX TYPE Page
    EFX Type: 2:OVERDRIVE

(3) Select the controllers you wish to use
    Patch parameter / PATCH EFX CTRL Page
    EFX Control Source 1: BENDER
    EFX Control Source 2: MODULATION

(4) Set the controller depth.
    Patch parameter / PATCH EFX CTRL Page
    EFX Control Depth 1: other than 0
    EFX Control Depth 2: other than 0
 
Using controllers in System mode
--------------------------------
Patch Control Source 2, Patch Control Source 3 and EFX
Control Sources allow you to select the SYS-CTRL1 and SYS-
CTRL2 settings, When these settings are selected, the Tone or
EFX will be controlled as specified by the controller selections
you make in System in System mode. In System mode, you can select
any control change number (# 00 - # 95), bender or after-
touch as the two controller sources, System Control Source 1
and System Control Source 2.

             System                       System
        Control Source 1             Control Source 2
           MODULATION                     BENDER
          /          \                       |
         /            \                      |
        /              \                     |
      v                  v                   v 
     EFX               Patch               Patch
Control Source    Control Source 2    Control Source 3
   SYS-CTRL1         SYS-CTRL1            SYS-CTR2
      |                  |                   |  
      v                  v                   v 
    DRIVE               LEV                 PAN
 Destination        Destination         Destination


It is convenient to use System controllers when you do not
need to specify controllers independently for each Patch, or
when you want to be free to use any control change number
as the controller.

* With some exceptions, the function of each MIDI Control
  Change message is predefined. For example of the Bank Select
  message (control change # 00, # 32) is used to switch sound
  banks. However the JV-1080 allows you to assign control
  change messages to a variety of other functions, so that
  sounds can be controlled in realtime. If you do so, however,
  you should be aware that such uses are outside of the con-
  troller operations defined in the MIDI specification.

Controllers in Performance mode
-------------------------------
In Performance mode, the control sources specified in the
Patch used by each Part can apply various effects to each
Part. However if you use the EFX settings of the
Performance, the EFX controllable settings of the Patch will be
ignored, and the EFX controller settings of the Performance
will be used. Also, if you wish to use controllers in
Performance mode, the MIDI receive switch of each Part
must be turned on.