High quality equalizers

I've been using a pair of Eargo hearing aids to compensate for my general hearing loss due to age and years in a loud workplace environment. Their top model (around $3000) is made specifically for hi-fi enthusiasts. There are 4 preprogramed volume levels and you can adjust the bass and treble response on one or both ears for each of the 4 programs. They also have preprogramed algorithms for such things as conversation, crowd, theatre venues, etc. Control everything with their ap on your phone. Totally invisible, FDA approved, and rechargeable. Made a big difference for me. Have very limited high frequency hearing. Worth looking into.

J.Chip

you could experiment also with devices such as a BBE or an aphex aural exciter, the latter has a midrange control that is good at boosting clarity of inner voices, plus a brilliance control on top and a big bottom" bass expander, as folks with presbycusis tend to lose bandwidth at both ends.  

Just picked one up from a Agoner in Michigan!  Couldn't recommend anything more.  Great for apartment living with limited speaker placement or hearing loss, et cetera

Connect-in before or after preamp ... couldn't discern notable difference; though I like it after so all sources can be adjusted.  Well made!!  You won't be sorry!

Hello,
The Shiit LoKI mini + is the Las test by the company. You can adjust the highest and lowest settings by 6db and the two mids by 12db. At $149 it’s very reasonable. I use this for my phone setup since it is single ended and lets me micro adjust the Schiit Phono stage to get dialed into my system. My preamp has a loop function so I can turn it on and off as I please but it is really for records due to my TT setup is on the light side. Another option is a used older equalizer which has a lot more adjustments and some cool lights. My local shop I frequently shop at in the Chicagoland area has used equipment you can try before you buy. https://holmaudio.com/
It’s like the ultimate candy store. 

If you stream roon has an eq setting you can use.