uce heavy vibrato. A major chord is when x=4, y=7.
     A minor chord is when x=3, y=7.

[1]: Slide up
     Where [1][x][y] means "smoothly decrease the period of current
     sample by x*16+y after each tick in the division". The
     ticks/division are set with the 'set speed' effect (see below). If
     the period of the note being played is z, then the final period
     will be z - (x*16 + y)*(ticks - 1). As the slide rate depends on
     the speed, changing the speed will change the slide. You cannot
 