I am in Ontario, Canada. Ontario Hydro has installed smart meters. To maximize their profits, they feed us 125V. Big problem.
Unless I'm mistaken, manufacturers try to build for 230V/115V. There is a bit of leeway. 125V is too high, and bad for music.
I have a power regenerator, and it's awful. Not recommended.
I have a Torus toroidal cleaner. 125V comes in, 120V comes out. Ideally it could be adjustable to 115V. Unfortunately it does not.
The Torus feeds a 'Balanced' BPT conditioner. What a gem. Fabulous. I believe Chris is now with Equi-Tech. Highly recommended. Ideally you should look for a balanced conditioner which also allows 115V operation.