Yes there is, but not in the way that ADSR operates.
the best way is to use PAAGE 7 and patch either VOLUME or AUX VOLUME parameters to a FUNCTION.
Page 48 of the guide shows how to do this for PAN.
Page 41 of the guide shows how to use FUNCTIONS
Page 29 shows how to use PAGE 7
Another way is to use Page 4 and to set a VOL profile - but this is not documented in the guide as it is a more advanced feature