@jerryg123 Good advice, thanks. I should have put a couple of dedicated lines in when I did the basement 10 years ago. Such regret that when my nephew told me he was creating a man-cave, I pretty much forced him into putting in dedicated lines..so much so I paid for one of the lines and sent him a couple of upgraded sockets to have his electrician install. Of course, his electrician was dumbfounded and my nephew (who is not an audiophile) was also incredulous on what I was telling him to do. I plan on using the Entech device to see how clean his dedicated lines are to what circuits I use in my basement.
Great to hear you have not had any surge issues! I told my nephew to plug his equipment straight into the wall and so far (maybe a year) he has not sent me an angry text that his TV was fried. So far, so good. A whole surge suppressor certainly would make me sleep better at night, although I have 5 power cables that need sockets, so I will have to use something to accommodate that reality when the time comes.
One last question, have you found that using a 20 AMP Power cord betters the sound coming from a 20 AMP wall socket/dedicated line, or using a 15 AMP Power cord in a 20 AMP socket is sufficient and sound-wise there is little to no difference?