I really appreciate this thread and hearing about other people's experiences. The topic feels timely for me.
I'm 48 years old and I have enjoyed accurate and quite full-range hearing through most of my life. But age and cumulative exposure seem to have taken a toll. A couple years ago when I was running frequency sweep tests on my system I noticed I had a strange hearing dropout at about 14 kHz. But I could hear 16 and 17 kHz above that.
Then a couple months ago, after a (superb) Tedeschi Trucks Band concert, I noticed a continuous, soft, very high-frequency ringing in my head. Tinnitus, it must be. It's in the top octave, somewhere around 12 or 14 kHz I'd guess. Especially when I first noticed it, this really bothered and scared me. I know there's no cure for tinnitus. Having my senses in good shape means a lot to me, of course, and I began to regret attending that last concert, not putting in earplugs more often at live shows, etc.
As I've done more informal testing since then, I seem to no longer perceive much above 12 kHz. Although I've enjoyed live music of many genres, including some loud concerts over the years, I've generally been careful about volume levels at home, on headphones, in the car, etc. So I couldn't understand why all of a sudden I was experiencing this. But for about five years, ending not long ago, I played bass in a garage band with some friends. We'd practice rock and blues every week or so in a basement room with cement floors, wood and glass walls: a very live room. The drummer played an electronic kit, and I stood pretty close to his drum amp. I also remember asking the guitarist more than once to turn down his amp because it was too loud for me. In retrospect, almost certainly those rehearsals did some damage to my ears. But I had so much fun with those guys. I would spend two or three hours not thinking about work or anything else except the music we were playing. It was lifegiving, but apparently with a long-term cost to me.
I'm less concerned about losing top-octave hearing. That happens to most people with age, and it's primarily overtones up there anyway. But the tinnitus is more obvious, something I'll have to work to make peace with. Already it's becoming a new normal for me. I notice that if I'm focused on a conversation or a task I might not notice the ringing for quite a while. I'm most conscious of it in a very quiet room or when I lie down to sleep. I continue to listen to lots of music but I'm even more careful about volume levels, and when I'm running a lawnmower, power saw, etc. I always put in earplugs.
Good things I've noticed: 1) The tinnitus doesn't seem to be getting worse. 2) The great pleasure of music is still with me! All the rest of my hearing seems to be intact and detailed — below those extremely high frequencies I still can hear everything easily. I detect subtle timbre differences, I can tell when a tweeter cuts out, I hear quiet details in nature and in music, I hear conversation over background noise, and so on. Well-recorded and well-reproduced music remains immersive and compelling for me. 3) This new experience of tinnitus has made me FAR more attentive to safeguarding my hearing. I'm hopeful that by being gentle on my ears I can keep this status quo for a good while.
So, friends, please be careful with your ears!