What about a high quality UPS? That cleans up pretty much everything in terms of AC line noise from other electrical equipment, voltage transients, line distortion (if you have it). It puts out perfect sine wave power. Plus, it would be a lot cheaper than some of the approaches mentioned such as the Shunyata Triton, or expensive rewiring of the last inch of electrical service.
I would note that a UPS does not typically provide galvanic isolation, and only secondary surge suppression.