IMHO, every designer takes his chosen technological elements and then finetunes them/voices them to make them as good as he can given the technology he uses and the budget he has set for production. There are great horns, great 3-cone, 3-way, 2-way, panel. Also depends on your budget. $500, $1500, $3500, $5-10K, 20K, 50K, etc...that also makes an enormous difference.
Because there are too many way to design speakers well...i would say the one feature i do find in common with nearly all great speakers...is quality of the enclosure. Very solid, no vibration, sometimes inert materials (resin-impregnated woods), aluminum frames...these materials usually speak to someone who spent time designing, is trying to create an inert box to be able then more consistently deliver sound through the cones, and create a more transparent sound. good luck. hope that was [a little] helpful...ask away with further questions.
Because there are too many way to design speakers well...i would say the one feature i do find in common with nearly all great speakers...is quality of the enclosure. Very solid, no vibration, sometimes inert materials (resin-impregnated woods), aluminum frames...these materials usually speak to someone who spent time designing, is trying to create an inert box to be able then more consistently deliver sound through the cones, and create a more transparent sound. good luck. hope that was [a little] helpful...ask away with further questions.