Natural tone
100% coherence from highs to lows -> solid timing-> musicality
Weight AND speed -> lifelike timbre, presence, immediacy
Pinpoint imaging -> instrument separation
Planars lack in imaging, single driver speakers lack in body/weight and tone on both extremes, 2 way dynamic speakers either in the bass weight and / or midrange transients. Most speakers have problems with coherence in mass and speed, especially ín the bass region.
Only the 2 way transmissionline speakers (good coherent bass speed but without weight) or 3 way speakers with small woofersize around 5" (-> speed, accurate timing, midrange driver got to have the same size) worked for me so far.