I use a Furman AR which keeps my line voltage within a consistent 118 to 122 VAC, barring severe issues (in which case it shuts off), as well as protecting me from white outs as well. The most compact/affordable combination is this unit.
In my case, I bought an Elite 15i first, and then realized I needed the voltage regulation, so I have probably spent 3x that much on my setup. Don’t do what I did. 🤣