-- card: 45568 from stack: in -- bmap block id: 0 -- flags: 0000 -- background id: 3551 -- name: -- part contents for background part 16 ----- text ----- 170 -- part contents for background part 3 ----- text ----- envelope -- part contents for background part 4 ----- text ----- a shape that changes as a function of time.The envelope shape is often in the form of a control voltage which can be applied to any voltage-controlled parameter of the soundto create a note shape.