Emu XL-7 & MP-7 User's Group

>>(2) How can you force pitch bend to play only notes in a particular mode/scale, specificially, the same one as the arp?<<

I've only ever been able to achieve this in the analogue domain, by routing the pitch-bend wheel (of any keyboard, but the control must be analogue CV, so a midi keyboard would have to be sent to a midi>cv converter) through a quantiser or "scale generator" such as the doepfer a-156.

I'm part-way through modifying a moog rogue so that it has an internal 8-step sequencer routed through one of these modules; the second channel will be applied to the PB wheel if I ever get finished.

I don't know of a midi event processor that can impose a scale on PB data, nor can I think of a simple way to do this within the proteus architecture, but there may be some combination of multiple wheel>switch>pitch patchings that will get you there. 

prob'ly use up all the patchcords.... :-)

another way would be to use layers that are tuned differently & use the wheel to switch amongst them; if you combine these two approaches, you might get close to what you need. 
the use of user tuning tables is a given, anyway, if you want the arp to stay in one key. :-)

duncan.