This is a good thread and timely to me too. I just added components to address my hearing (hi-freq) loss. Some ask, why not get hearing aids? First, as noted above, the brain adjusts and I thought I had fine hearing. Still do! Second, if I know what is missing, why not adjust all of that marvelous gear instead of asking something that's miniature enough to fit in your ear to do it. Bass? OK, your system might not be "correct" to others but for many, that's a moot concern.
I just posted a few days ago here on AG about using EQ to adjust per audiogram results. As my losses are inequal by ear, I need to have L and R ch. I opted for quality Schiit EQs and installed one in each channel of my pre-amp's processor loop. A customized EQ profile for each side has returned subtleties I suspected were fading but now back. Waaaay cheaper than chasing speakers when what I have is better than fine. However we choose to get along on our issues, enjoy.