anchor.diff:                          -3 -10 -8  -7
                           -5  -3 -1  -5
                           -8 -11 -6 -14)
  -                      '(11 11 11 12  11 11 11 12  11 11 11 12  11 11 11 13))))
  +                      '(11 11 11 14  11 11 11 14  11 11 11 14  11 11 11 15))))
   
   (defpattern bassline-1D ()
     (apply 'seq (mapcar (lambda (pitch duration) (tri 16 (et pitch) :d duration))
  
positive.code: (nesmus:define-song "Steps" ())
  
  (defpattern bassline-1A ()
    (seq
     (tri 32 (et  -1) :d 31 :vibrato-delay 12)
     (tri 32 (et  -3) :d 31)
  
     (tri 32 (et  -5) :d 31 :vibrato-delay 8)
     (tri 24 (et  -7) :d 23)
     (tri 24 (et  -9) :d 23)
     (tri 16 (et -10) :d 13)
     (tri 16 (et -12) :d 13)
     (tri 16 (et -13) :d 13)
  
     (tri 16 (et  -3) :d 13)
     (tri 16 (et  -5) :d 13)
     (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)
  
     (tri 32 (et  -9) :d 30 :vibrato-delay 8)
     (tri 24 (et -11) :d 21)
     (tri 24 (et -13) :d 21)
     (tri 16 (et  -6) :d 12)
     (tri 16 (et  -2) :d 12)
     (tri 16 (et  -6) :d 14)
  
     (tri 16 (et  -7) :d 12)
     (tri 16 (et  -5) :d 12)
     (tri 16 (et  -4) :d 12)
     (tri 16 (et  -2) :d 14 :vibrato-delay 0)))
  
  (defpattern bassline-1C ()
    (apply 'seq (mapcar (lambda (pitch duration) (tri 16 (et pitch) :d duration))
  
negative.code:                         -7 -5 -3 -2
                          -9 -2 -5 -8
                          -11 -8 -6 -14)
                        '(11 11 11 14  11 11 11 12  11 11 11 14  11 11 11 11))))
  
  (defpattern bassline-seq-1 ()
    (bassline-1A)
    (bassline-1B)
    (bassline-1C)
    (bassline-1D))
  
  (defparameter *sax-config* '(:env nil :loop nil :duty 1 :vol 7))
  
  (defun bup (note length &key (d (1- length)) vibrato-delay)
    (para
     ;;(note 1 length (et note) :d d :cfg '(:env nil :loop nil :duty 0 :vol 6))
     (note 0 length (* (et (+ note -1.6 ))) :d d :cfg *sax-config* :vibrato-delay vibrato-delay)
     (seq (list (list (register 1 #x8F))
                nil
                nil
  