We use Rare-Earth metal in our Epic speaker magnets. Rare-Earth metal holds a very high magnetic "charge." As such they provide a much higher magnetic flux density in the air gap and so can generate a much greater action force in the voicecoil. What's this mean to you? They sound really, really good!
Holy s**t do these things sounds good!
Got my Volic headphones installed on my Icon Airflite and holy s**t do these things sounds good... they sound just as good if not better then my Beats Studio headphones.