How do I put an effect on just a part of music?

Hello, I was playing around with my music and I was wondering how to put an effect from the beginning to a particular point in the music. Right now, I am trying to use Sliding Time Scale/Pitch Shift and make the music completely go down at a particular point. Help!

Drag-select in the blue waves from the beginning to the particular point. See this question in the Manual: .


Effects and other tools only work in sound that is selected.