PROCEDURE quartet_4q(song$)
  '
  ' song$ = the name of the QUARTET 4Q file to play.
  '    NOTE: The file must exist!
  '          This routine does NOT work uncompiled!
  '
  IF xquartet%=0
    RESERVE 20000
    xquartet%=EXEC(3,"singsong.dat","","")
    ~MFREE(HIMEM)
    ~MFREE(xquartet%)
    RESERVE
    ~MSHRINK(xquartet%,16384)
    ADD xquartet%,256
    song%=xquartet%+17000
  ENDIF
  BLOAD song$,song%
  @ice2_240(song%)
  {xquartet%+12}=song%+20
  {xquartet%+16}=song%+{song%+8}+20
  @jsr(xquartet%)
  SOUND 1,0,0,0,0
  SOUND 2,0,0,0,0
  SOUND 3,0,0,0,0
RETURN
> PROCEDURE ice2_240(location%)
  INLINE ice2_240%,404
  {ice2_240%+2}=location%
  CALL ice2_240%
RETURN
> PROCEDURE jsr(location%)
  INLINE jsr%,16
  {jsr%+6}=location%
  CALL jsr%
RETURN