I have a transparent power isolator and many of their Power cords. Glad to hear it reduces the noise. I’m skeptical about noise analyzers because they tend to make the problem sounds really bad by amplifying the noise so you can hear it. But if you move them around to different outlets in your home you’ll see differences. How meaningful this will be to your system is anyone’s guess.
Even dedicated circuits Will share noise from everywhere else in your house. I installed a dedicated circuit with 10 gauge wire so the electricity supply would be more responsive to audio system demands, ie. Not impeding those electrons.
Also skeptical of really nice power cords being recommended to attach to a company’s power conditioner. They contend it makes it even better. It may make things better like they say.
Nevertheless, if your system is very revealing and on the upper end, having well shielded power cords and an unrestrictive power conditioner has merit.