[changing the settings of Curve and Treshold does not bring me the effect that I like.

I Bert, I would like to help you, but;

1-Which instrument are you referring to.
2-You may have to edit the sound of the instrument you are using, then use Touch Sense, Curve, and Threshold.
3-Most of all, what we hear is so subjective. What I love, you may dislike.

I need more info to help.

Take care, John C.