Earlier in my longer post I said the average highest hearable frequency for an adult (starting from 18 years old) was 12 kHz. This is an average value that was measured by audiologists on a randomized population and compiled for a study paper I have once read in my class. Audiology isn't interested in the highest hearable frequencies usually but this was a special case... and I do remember having read this fact, three years ago in my class.
All that I am saying is that the 20 kHz on mosquitos ringtones, on YouTube, and in an audiological cabin are all different frequencies. Which one is the right 20 kHz? I believe it would the one you hear using the red and blue Sennheiser headphone at an audiology clinic when you do a hearing evaluation, you just ask the audiologist to go beyond 8 kHz, he shouldn't matter doing it but he'll warn you that you might not hear anything above 12 kHz. I asked my friend to do it when he evaluated me for his homework; the cabins are brand new and impressive, just like the classrooms. I'll see if I can find back my audiogram that he produced of my audition; it was above average for the 125 to 8000 band.
The numbers on YouTube and especially on MosquitosRingtones are inflated and distorted. 21 and 22 kHz must be arround 13 to 14 kHz, not more.
You're are right about the fact most of my class was hearing the 20 kHz; but that was the MosquitosRingtones 20 kHz, so maybe it's not 20 kHz.
Only newborn infant can hear the 20 kHz ultrasound... at 15 years old you're at about 15 kHz, and at 12 kHz, when 18 years old. It is the point when you're considered fully grown for the most part and your skull has fully ossificated and hardened. Also keep in mind that those are mean numbers. Someone healthy who doesn't listen to loud music, work in noisy environnements or often go to concerts, might be able to hear a bit to a lot more than those freqs.
I am also of the ones who believe that depending on the time of the day (after a good night of sleep), on your focus (destressing the middle ear's muscles to lower the compliance of your tympanic membrane and reduce the self-induced tinnitus (which is the tiny and very real noise that is emitted from your eardrums after you've been exposed to a noisy environment, a very physical and tangible form of tinnitus that one of my teacher claim to be able to hear coming from her patient's ear in a fully dampened acoustical chamber), your alimentation (there are pseudo-scientifical evidence that juice full of anti-oxidants such as grape, blueberry and pomegranate can help preserve your audition when aging) (but overall eating varied vegetables and fruits is always a plus), you can hear higher freqs.
Quote:
Originally Posted by Mischa23v
Your contradicting yourself ,” the big majority of the class at 20 kHz, there were four girl's hands remaining at 21 kHz, and only the very youngest of our class could hear the 22 kHz one, she was also 18 about to turn 19.”
