FWIW I have also lost a little of the high end. I bit the bullet and just accept the fact that it ain't what it used to be. I tried equalizers (in a tape loop) and while I felt they were helpful in changing the overall tone of the system they didn't really help to restore the high end. Ditto, hearing aids. When I get to that stage then I get an equalizer and headphones! :-)
High Frequency Hearing Loss
Unfortunately over the last few years, I have developed a significant high frequency hearing loss beginning around 6k Hz and upwards. I notice it in the way recordings with cymbals and other high frequency percussion instruments are much much duller than they used to be. Violin music has lost some subtle overtones that I used to hear. What is the best way to deal with this? I was thinking of getting a DAC like a Weiss 501 that has built in DSP features where you can try to offset the hearing loss by boosting the frequencies that have been attenuated. It seems like it's one of the few DACs that have this but it's not cheap to say the least. Is this the best solution or is an equalizer in the analogue domain a good/better solution?