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What you are failing to recognize is controlling the internal PARTs of the Motif XF is clearly easy. It is designed to control its own internal Parts in Performance mode. Controlling your external device (what you repeatedly refer to as the "FW PART") is a matter for you to look up in the manual of that device. It (Ivory) is not a PART of your XF, it is external, and therefore is treated as an external device. If it responds to cc007 (Main Channel Volume) and cc011 (Expression) - these are standard MIDI channel messages to control output level. You simply need to accommodate it with one of your (non-fixed) assignable controllers.

cc007 forces all devices on the channel to the same exact value. (Absolute volume)
cc011 changes the volume of all devices on the channel but keeps there relative proportion.

Moving a controller sending cc007 to a value of 50 forces all devices on that channel to a value of 50
Moving a controller sending cc011 will allow the Piano set to 100 to remain twice as loud as the Strings set to 50, even as you fade them out. Reduce the Piano to 80 the Strings reduce to 40 (Relative volume) the proportion remains in tact.

Make sense?

MIDI Rules are strictly adhered to by Yamaha
Now, by the rules of MIDI, the Modulation Wheel always sends cc001 "Modulation Wheel". It can send no other Control Change number, it is a "fixed" MIDI control device. On all instruments that strictly follow the MIDI spec it is fixed to send cc001 - what that does in the receiving device is totally dependent on what you assign it to do in that device. What you can do is program what the receiving device does with cc001. For example, you could program any of the internal Motif XF Parts to respond with volume change when you move the MW. You cannot reprogram the message the MW sends, you program what the receive device/Part does with cc001.

Make sense? If Ivory can only respond to cc007 or cc011 for volume change, this is NOT a problem. But forget about the MW then. That will never happen.

They said:
" I think the simplest way to control the volume of Ivory from the Mod Wheel is to look into the options of your controller keyboard, and see if you can assign the Mod Wheel to send MIDI CC#7 (volume) or MIDI CC#11 (expression).

Sorry but what they told you is contrary to the rules of MIDI... Yamaha is one of the founding Midi manufacturers and we follow the rules of the specification. You cannot change what the MW sends, what the PB Wheel sends, or what Aftertouch sends... You change (per VOICE) what it does within the Voice. There are 101 Destination parameters for any of these controllers for the internal XF Parts.

What we suggest
In fact, no programming is necessary: a Yamaha FC7 pedal plugged into the Foot Controller 1 jack automatically defaults to sending cc011 Expression. This will solve your problem. All Midi devices on the channel will respond to this Control Change message. You can tell the internal Parts to ignore this message, this way only your external device will change. Each internal XF Part has a RECEIVE SWITCH where you program what controllers it will or will not follow.

Do you have an FC7 pedal?

If not, let us know - we can offer you some alternative methods using other controllers or using the MASTER mode. Where your CS (Control Sliders) default to sending cc007 Main Channel Volume. Master mode's purpose is for when you want to control both internal and external devices. The external device is never considered a "PART" but we know what you mean... As long as understand it is external.. Completely external and not subject to the same rules or features as an internal Part

Let us know. An FC7 pedal is the most elegant/easy way.

Thanks. Yes it now makes sense. I do not have a Fc7 pedal so I would be interested in how to use other controllers and Master Mode.

Please see the following articles for information concerning other controllers:

_ Physical Controllers and Destination Parameters

_ Understanding Master Mode

If you still have questions, please post specifically what you are dealing with (without specifics we can only guess about your situation and how best to accomplish your goal). In Master mode, when the Zone Switch is active and you press [PERFORMANCE CONTROL], you can turn ON and OFF each Zone using the buttons 1-8 (Internal Zones) and 9-16 (External Zones)...

What you will want to setup is to create a situation where you are addressing each internal Part via an XF internal Zone Switch, and you external device on an External Zone Switch.

(Of course, you could just purchase an FC7... How can you play gigs without one???)