Who uses power conditioning?

Inakustik AC-3500P power filter. Best power filter/conditioner I’ve owned. 

May I recommend a look at the ADD-Powr Sorcer EMF conditioners.
There is nothing out there like it, I swear.
Energy can neither be created nor destroyed only changed in form,  but it can be given a kick or a boost!
We have disrupted the old standard. Ha!
So now in 2019 there is a new approach AND a New Reference!

High Fidelity Pro Power conditioner here

Hello,

I have used a Tice power-block { larger old unit but works perfect } to feed my tube mono blocks, preamp, etc.   for many years.  Being an electrical engineer I can tell you that there is measurable noise on just about any AC line. 

If you want to save the money, you can go with a surge-suppressor AC outlet { amazon } or at least a decent power strip with one in it.