Let's all agree on one thing: you do not want to plug your stereo into your neighborhood grid. Your music can only sound as good as the power that drives it. Noisy and dirty power is found in every outlet and if you care about your music, you need to find a way to block that gunk from your music. There are a lot of thoughts on the subject, and methods to scrub that power but it still boils down to you dealing with the issue. Power management unfortunately is also a complicated issue and prone to oversimplifications and bad advice. There is no one single perfect way to tackle this issue for your stereo, but there are a number of reliable paths and with the guidance of an experienced partner you can implement a solution that meets your needs and leaves you to do what you want to do: listen to music.