What happens when a DVD that boasts a 6.1 DTS ES or Dolby Digital EX soundtrack is played back through a 5.1 system? Is anything "lost" per se without that sixth back surround channel? My receiver does decode DTS ES and DD EX signals, but I am only running a 5.1 array, yet I choose DTS ES and DD EX soundtracks from DVD menus when they are available----what happens when you play back films with 6.1 channel soundtracks through 5.1 systems? Is the "extended" sound somehow being "ghosted" or "matrixed" between the standard surrounds?