The Absurdity of it All

Spoken like a young fella!  Full of wrong science.  On average we lose the edge with time, but there are those who hear perfectly well into very old age.  Just as some are deaf from birth, some are spared. 

The second important feature mentioned earlier is the brain.  Studies in dementia as related to age and Altzheimers find that as the brain losses it's functions the centers that process hearing and MUSIC are the very last to go.  I saw Chris Christopherson in concert on stage by himself for 2 hours with a short break.  He said hello and went on from song to song.  It was a perfect one man show.  I noticed at the brief break a stage person came out and escorted him off stage and then back on again.  The music continued without a stitch out of place.  One month later they announced that he was retired and suffering with advancing Altzheimers. 

He may not know his name or who his closest family members were but could pick up a guitar and sing for hours.  It was also noted that his final concerts began with the first song he wrote as a child and that every song that night was in the exact order he wrote them over a lifetime.  So, ya, there is the brain and a perfect set of youthful ears matched to a fine stereo system blasting away with some Kiss or Lead Zepplin may help kill some brain cells.  Then to shut up long enough to listen to George Shearing and Mel Torme... well, I know that is not apt to happen.  

You can drop a needle on vinyl and I can tell the 1950s & 60s 'Decca' recordings from RCA's.  I can tell when 'mono' became 'High Fidelity" from a vinyl 'Stereo' that followed.  The highest qualtiy recordings are still fantastic and the market was filled with some real cheap products.  I can hear that.  I can really appreciate putting a 180gm record on a $2,000 Rega turntable with a $500 cartidge and fine valved pre-amp.  

It reminds me of being a kid in the 1950s.  My dad taught school and with 5 kids there was little extravagance.  Eating shrimp was one of them.  At an early age I looked at cocktail shrimp and asked, "What is that?"  I had a naked shrimp shaken in my face and asked if I want one.  Hell no!  It was on food on my plate that I was not expected to finish.  My mom and dad got all the shrimp and they gave me my wish, Spaghette-Os.  

After 70 some years I love to eat shrimp while listening to the wide range of music that I also love.  I hear some much more than a bowl full of Spaghetti-Os.  If you need some help with that get back to me.

This is THE answer (seriously):

Physical hearing parameters of a person that a machine can measure - tell you next to nothing of importance. 

It's discernment which is all. The ability to ascertain nuance that younger minds & personalities have not the intuition to perceive. It's a matter of maturity & wisdom.  If you've bothered to cultivate them you reap the fruits. Even if you haven't you usually to some degree have some extra measure of them, unavoidably.
It's not completely different (although more so in audio) from tastebuds being able to technically discern less as you age - yet if you've matured well & with some effort kept yourself perceptive & open-minded - the amount of nuance you can spot in food is far higher - even if the splashy extremes of spicy/sweet/tart, etc aren't so vivid. With your ears you don't need to concentrate to that degree, the cues are manifold & the lifetime of learning & practice amplify all the good things that more aggressively presented themselves when you were younger. Subtleties are hardly passive, inert things when you know their significance & how to let them register & trigger a depth of emotion - that was far more two-dimensional once.  You hear more of significance - not less then.

Thank you @bstbomber & @rcronk for those well reasoned thoughts.
One can't forget that in addition to our unique set of ears that they've been working in concert with our unique brain and continue to do so.

Our ears don't operate in a vacuum. Cherry picking them out of that equation and then breaking out that hoary meme of what we can't hear past a certain age ignores the rest that we can hear, or it's hoped that we overlook it and fall for it.

All the best,
Nonoise

If it sounds good to the listener, or better after experimentation, who cares how it measure or what anyone else hears? Extended listening vs. short blasts of A:B, a good discussion for a new thread perhaps. 

So I’m 51, and had my hearing tested a couple of years ago. I asked if my score was a pass for a 49 year old, and he said that my score would have been acceptable if I was eight. That said, I know I have lost some ability, and gained a little more background noise. Not horrible, but it’s there.

I was making a decision on a new piece of gear last week that I was auditioning - an EMM Labs NS1 streamer, and comparing it with my tried and true Bluesound Node 2i. I was always under the impression that the streamer really didn’t matter as long as all the bits were there. The magic really happens in the DAC, which in my case is also an EMM Labs. Much to my chagrin, I heard some very large differences between streamers both going into the same DAC. Was it a bias? Is my hearing even good enough to hear the differences?

i enlisted the help of my 14 year old freshman daughter. She loves music, but has no interest in high fi. I promised her a simple A/B off four tracks, one of which she knows very well from her iPhone and Beats. Surprisingly, she listened to A (Bluesound) and then sat up straighter when I switched to the NS1. She had no idea of what I was switching, by the way...I was able to leave everything connected and A/B with the remote. I switched the order up on track 2, left the same order for 3, and then back to the original order on track 4. I didn’t even tell her what to listen for. She picked out almost everything that I picked out in every track. The sound of actual air coming from a saxophone. The clarity in background farming parts. One guitar turning out to be three, sequenced over each other. The familiar track was Taylor Swift’s August, and she was like, I have never heard this song sound like this. So, my findings verified, I bought the NS1. My stayed in the room and listened for another two hours to so music of her choosing. (Priceless to me.)