Here I have assigned Modulator 4 to control 2 parameters - Gain and Frequency for Band 2 in an EQ (hence the green tone to the style
) and set the desired ranges for each. On the Envelope tab I then edited the ADSR curve (strictly it's a DAHDSR curve) to be as I wanted. Next I started playback and set the Threshold On and Off positions. When the audio level exceeds the On level then the ADSR envelope starts and changes the target parameters; when the audio level drops below the Off level then the Release stage of the ADSR envelope starts and changes the target parameters.
Let's have a closer look at the graph. I have popped up the graph into its own (resizeable) window and marked the On and Off trigger points with white and yellow rectangles respectively. You will see 3 of each. The dB scale on the left-hand side is used for the audio level and the % scale on the right-hand side is used for the ADSR envelope.
The audio level is the orange-brown line and the triggered ADSR envelopes is the blue-grey line. Each time the envelope is triggered it rises to 100%, holds there for a short while, decays to the Sustain level (50% (= -6.00dB)) and each time the envelope is cancelled it starts the Release stage, falling down to 0% (silence).
The first envelope is very quickly followed by another so the Release stage is interrupted and the envelope rises again to 100%. Similarly the second envelope is interrupted by the third. The Sustain stage of the third envelope runs for some time until the audio level drops away, the Release stage then starts and has time to drop down to 0%. Please note that the third envelope is not interrupted by a fourth / fifth etc trigger as its Release stage had not been started.