Altura or PITCH will change the pitch acordingly to the selected value
Default that value is 0, meaning that there are no change of pitch.
Press a note and turn the Altura dial.
Now you will hear how the pitch variate, like a 'slide'
The whole span of pitch-change is 1 octave
But the 'extensión' roller, will add more and more octaves to the span. At the time any movement of the Altura-dial will course more dramatic changes in pitch