I’m 69 and have been using headphone noise suppression for over 30 years, when I mow, use power saws, vacuum or do anything that involves loud sounds. I have three different SPL apps I use. All three are within a couple of db of each other. I’ve found that iPhones are a good piece to measure with. Generally, I don’t go above 85 and tend to stay between 70-75 db. I attended aDoobie Bros Concert a few months back in Nashville. I forgot my foam buds, so put tissue in my ears. I measured a SPL of 106 db! They played great, but way too loud.
two years ago, I could hear 12K Htz. Now it drops of around 10.5Khrtz. My listening sessions are getting farther apart, but still love to have a night of good listening.