He went in for his annual physical, and the doctors revealed that his hearing was deteriorating and that he needed hearing aids in both ears. Now with his new hearing devices, he once again a "Happy Camper".Thats exactly the point Ive been trying to make. You dont have to have severe hearing loss before it affects your ability to hear.
Everybody has a different hearing response. This can be proven by having a hearing test. Your hearing test results will be different to the speaker designers test results. So even if you were sitting in his chair, youd still be hearing differently. Now factor in your room, your preference, your music, your chosen speaker positioning and its obvious that what you hear is not going to be anywhere near what the speaker designer hears.