My wife just got a set of real good hearing aids. They were said to have cost $ 5,500. Luckily we didn't pay that for them as she inherited them when her Mom passed away. Her Mom never really used them because like a lot of folks she prefered NOT to hear. The TV was always at 80.
We paid $ 500 to have them re furbished. They tested her in a sound proof booth ( I want one) and her EQ curve showed falling off sharply in the high end. She worked in a dental clinic for 30 years and we think it was the ultrasonics.
Anyway I became "enlightened" to the technology and how it works.
We audio dudes at least understand what a EQ graph looks like!
The hearing test results in a frequency graph for each ear.
The technician simply overlays EQ until they get closer to a flat response on the graph.
They use a bluetooth system to access the guts of the aids.
It's special software etc. very impressive.
She immediately noticed the difference and now could hear sibilance in speech. At first she didn't like it but gets better as your brain re adjusts.
But as far a musicains go, you can accomplish the same by having the test, get a print out of your graph and simply EQ your listening system. Most of us can make up for having a bumpy EQ graph as we "learn" our monitors etc. But if that EQ graph is way off in a few places your brain will not be able to compensate.
In a live band situation we use in ear monitors now a day's. Hearing aids don't work well with amplified sound. If you havn't yet gone with in ears, do it. I use a hardwired system. Wireless costs way to much and is only really needed if you're running around the stage.
In the studio I imagine they would solve the problem to a point, but just like in ears, your going to have to pay top dollar to get hi fi sound. I would say, EQ your speakers to match your personal short comings. Hearing aids will probably diminish hearing the full spectrum and make it harder to mix properly. You might as well wear open back headphones.
Hearing aids that don't have EQ are only little amplifiers and do not solve the real issue with most types of hearing loss.
At the care home where I work we use "pocket talkers" with much better results than cheapo hearing aids.
A pocket talker is a small amplifier with an omni mike and a set of headphones. You can wear it around your neck or ,like the title says, put it in your shirt pocket. They are not very glamorous but do they ever work great.