I know what you mean, I asked them once myself as you I was astounded, If you want me to answer it I will? On a footnote supposedly they have a new line of heads coming very soon thats suppose to be the stuff. Full open tone with no extra muffling required.
Up to you my friend. I guess it isn't an industry secret as such. Just a nice bit of trivia. :p
Looking forward to trying their new line. They do need to keep things moving as a company, although they must hold onto those classics to.