With regard to damaged hearing...
Etymotic Research, the global leader in these things, has fought and finally won a long battle with the Feds to be able to offer a prescriptionless Quiet Sound Amplifier (the "BEAN") that for $214 per ear offers state of the art amplification of the soft, high frequency sounds that typify hearing damage.
Read the "I've got BEANS in my ears!" review on their website
https://www.etymotic.com/consumer/personal-sound-amplifiers/bean-qsa.html (Page eight) for feedback from a user who had for 20 years invested in the "state-of-the-art" (non-Etymotic technology) hearing aids, most recently the Starkey SoundLens @ $4K each, and reports the BEAN Quiet Sound Amplifiers to be far superior.
I've recently begun using them myself, and wrote the (currently Page 1 but with webmaster fixes needed) "Stunningly Effective Product" review which, btw, should end at the "*see Etymotic's History with FDA, under Background of BEAN Development" footnote, maybe 8 lines down. Use of 3M 1100-based seals provides for all-day comfort in my hypersensitive ear canals.
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