Well, you can pay for a $189.00 or so for a Tripplight isolation transformer.It has 1800w capability and regulates down to 85v to 145v to 120v. It also has RFI suppression. Filters spikes and noise. I use a Furman power strip in front of that which also has RFI filtering and a 145V clamp circuit which shuts down power at that Threshold to protect the isolation transformer. Probably under $300 total. My primaluna is silent with this turned up loud. No hum no hiss. Or you can pay thousands if that makes you feel better. I dare to compare. $$$$$$$ does not always add up to better sound.