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

Sometimes I use my old Wacom tablet as a controller with software called wmidi on WinXP. It has about 300 scales. It won't convert major arp patterns to minor patterns to track a particular key, though. It will let you use the tablet pen to play notes in a particular scale. It can be found at: http://www.nicolasfournel.com/.

If you can get Jan Eidtmann's Prodatum software to work properly (I have had problems with later builds), it has an arp editor which beats using the front panel. You cannot shift and insert notes, but you can do some fast on the fly editing.  Proteum also has arp editing, but I haven't played with that feature enough to remember what it does and how it works.

I have experimented with midi data processing using a language/environment called ChucK. Its a bit buggy on a PC, it is supposed to be more reliable on Macs. You could probably write a script to play arps based upon a desired key. It would involve taking midi data from a controller, processing it using your script, and sending it to your sound module.

Hope this helps.

--Steve

PS: Welcome to the group!!!