Here's a short demo of the Chase function offered on D-50.
Although its not an arp., it's a useful feature. The Time and Level of 'Chase' can be changed to effect how long 'Chase' will occur and how loud the delay/echo of each note will be.
The speed can be varied as well. There are a few configurations of U & L that can be specified by the user . Those setting are: U/L, U/L/L, and so on. :) TSF