Hey, thanks Adam!
Now I don't know why I'm admitting this when I needn't... but
I actually have a KP3 sitting at home that I got 2nd hand a couple of months ago, checked
out the pad works fine, tried out some of the effects algorithms, tried out as a midi
controller for an analogue filter and then haven't got round to exploring any more yet!

Looking again at the manual, I can see programs SMP3, SMP4 and SMP5 look like they
should do the sort of thing I'm talking about.
Time to get that plugged in
again methinks...
(Damn, there goes my excuse to buy an SU700!)
Thank you very much, again!