anchor.diff:  (nesmus:define-song "Steps" ())
   
  -(defpattern bassline-1 ()
  +(defpattern bassline-1A ()
     (seq
      (tri 32 (et  -1) :d 31 :vibrato-delay 12)
      (tri 32 (et  -3) :d 31)
  
positive.code:    (chord 24 7 -0.3 t    10  6  4  1  -6)
     (rst 16)))
  
  (defpattern song ()
    (seq (para (bassline-1)
               (sax-1)
               (chords-1))
         (para (sax-234)
               (seq (bassline-2)
                    (bassline-3)
                    (bassline-4))
               (chords-234))))
  
negative.code:    (tri 16 (et  -6) :d 13)
     (tri 16 (et  -3) :d 13)))
  
  (defpattern bassline-1B ()
    (seq
     (tri 32 (et  -5) :d 30 :vibrato-delay 12)
     (tri 32 (et  -7) :d 30)
  