You can also see on this picture that each track can be associated
with a playback volume. In this example, the Background music
would be played at a lower volume than the Voice
track.
Furthermore, each track has a playback envelope, that is represented
as a thick blue line which connects knobs. New knobs can be added to
the playback envelope by simply clicking on it. A knob can be removed
by dragging it out of the window. The first and the last knob are
fixed and cannot be removed. The playback envelope allows you to
change the volumes of different sections of a sound independently.
The Apply Envelope to Track function from the Sound menu allows you to apply the playback envelope to the current track. Here is an example illustrating this:
In the first picture, you see a track with a volume envelope that causes the volume of the track to gradually increase from 0 to the maximal volume. After selecting Apply Envelope to Track, this changing volume has been applied to the waveform, which you can now see taking increasingly larger values as time goes on. The playback envelope on the other hand has been reset to the default value of being constant at the maximal value throughout the whole track. Playing back the track produces the exact same output in both cases.
