i went from nothing to adding a new couch (helped absorb sound reflections), rug, denon receiver, dvd player & a focal 5.1 setup. i did ALOT of research & set it all up at one time so it would be perfect right off the bat, calibrated, etc... but 2 months later i upgraded the center channel to one of focals higher end center's & WOW! by far the biggest improvement, even over speaker placement.