Surprising as it may seem, I started this process by reading the manual. It says to add vibrato, I need to turn it on and set its depth with aftertouch, and control its speed with CC17.
So, I created a note expression that sends Controller 131, value 127 (probably too much but at least I could hear it), and a second note expression that sends Controller 17, value 50. I applied these expressions to subsequent notes to a JABB Soprano sax line, in that order.
I got nada. Not even the slightest quaver.
I don't know what else to try. I've tried several different controller numbers instead of 131 (depending on what internet source you want to believe) and none of them work.
I just want a little vibrato...any help is most welcome.