Visions,
Generally speaking the PLG100XG would seem to be a poor choice to add to the 9000PRO. First, the 9000PRO already has XG voices, so the only thing you could get is more polyphony. Second, since the nature and propose of the PLG100XG is multi voice tone generation, it only works in Performance or Song modes. The 9000PRO doesnt have a Performance mode, so now you're limited to Song mode (if even that will work). I haven't tried anything with it yet, because I don't know your application yet. Let me know what you're trying to do, and we'll go from there.
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Steve Deming
Assistant Manager
Customer Support Dept.
Pro Audio & Combo Division
Yamaha Corporation of America
YCASupport@yamaha.com
714.522.9000