As i remember my old 808 drivers with annular slit phase plug sounded way smoother than my new Great Plains 802 with the Tangerine phase plug. My old drivers had the new great plains diaphragm so really the difference between drivers is the phase plug. In my opinion the Tangerine phase plug sounds harsh the highs are not that pleasing think i am going to buy some old annular slit altecs put new diaphragms in the them and compare the two but i think the older drivers are going to sound better so i may lose a little highs but i am 44 i don’t think my ears will mind.