what about around 20khz, they say we hear it but i guess not at least after 60 years of doing everything to destroy my hearing, one when young never thinks that will live far but so many that are not amongst us and had very healthy lifes , well to their way of thinking because living healthy as described sounds more like not living at all , not only our hearing ,food also . What makes food better is bad for our health or heavy tastefull ,i stoped having care or we go and not here at the fullest , a good wine and a good fish or meat is imperative or what are we doing here?if not to enjoy life as best as it can be done , Music makes a big part of my life since i was a kid , i found a film saying my name with 3 years old, well i was trying to tune a guitar and singing but i only remenber having taste for music when 11 or earlier i still remenber what music i heard while my mother driving a mini or my father to not get out of the car to open the gate of our house he once broke the all front of a old mercedes, i think it´s the one i have still with some fins ,S class past type maybe in 1966 but a 61 car after he bought a Citroen DS19GT that i still have also, memories we all have them, about frequency´s the cabinets where my records are stored have big framed glasses to be closed and see the titles but the glass when the bass is too strong i can´t hear it but the glasses of the cabinets starts vibrating ,a lot so i guess the 20hz are gone too