I suspect a few of you might find this post of interest regarding “noise” in cables and audio gear. I am on the Board of Directors of Verdigris Technologies, if any interested it is an AI company for managing electricity (www.verdigris.co). We got our start by recognizing that anything plugged into an electrical circuit, not only draws power, but also emits a rather unique signature back into the electrical circuit. The challenge is that as multiple electrical appliances are plugged into a single circuit, the signatures are all jumbled together. We developed unique technology that enables us to disaggregate all those jumbled signals to identify exactly which products are plugged into a circuit, and even identify early warning signs of failure, and we have patents regarding this technology. My point in all this is that it is clear that anything plugged into a circuit carries these multiple signatures from whatever is plugged into the circuit into any audio equipment plugged into the same circuit, and it is logical that at some level the garbage noise is is audible. So I think that it matters a lot how electrical power is managed, and that includes the cables used at each step of the audio food chain. Many of us don’t have the ability to have a unique circuit for just our audiophile gear, which is probably the best alternative, and so need to rely on products like regenerators and cables that reject noise to attempt to clean up and eliminate these unwanted garbage signals.
Thanks for the insight. Very well explained.
Those who live near industrial areas know this all too well. The AC we all receive from the power companies is not pristine.
Very interesting topic that confirms my experience. I’ve discovered the hard way that certain categories of products when plugged into the same AC circuit as my audio system are particularly pernicious. Wall wart powered computer gear is anathema in general and I won’t allow any switch, or router, or ethernet adapter ect. to be plugged into the same circuit as my rig. The hash emitted by those devices back on the line can be so intense a power conditioner is inadequate to suppress it. That is what happened to me a couple of years ago when I plugged AC line ethernet adapters into the circuit I power my audio gear with. It was … obnoxious.
What do you mean?? It can be as pristine as water from a cesspool!!
I remember back when I owned some tube gear and it had the standard IEC power cable and the only way to get rid of the hum was to use a ground lift gray adaptor on the plug. I am using affordable Furman power conditioners on all my gear and I have had no issues. My computer noise floor in my recording software is -80db. Most of my mics have low self noise, except my Sennheiser e865 vocal condenser that is -23db. AT $265 it is pricing for a vocal mic, but I gave it to my son for his twitch streaming as the noise from it was just too noticeable. I won’t buy anything now that is over -17 db of self noise. My Rode NT-1A have only 5 db of self noise.
I wish $265 was expensive for a vocal mic. 
But it is more than the $100 one spends on an SM57 or SM58 for garage band/bar stage use.
The Rode M1 (3) vocal mics are great, quiet and only $99. The SE Electronics V7 is also quiet and a nice vocal mic at $99. Their V7x is their (SM57) dynamic instrument mic and is also $99 and quiet. I also have 2 of those. I have 3 of the e835 vocal Sennheisers which are quiet at $99 each, but the $200 Senn e945 is great , very quiet and sounds superb. I have 3 of the Rode NT1As (5db) and two of the SE S7 pencil uni condensers and are quiet at 17 db of self noise. The 2 Senn e614 uni pencil mics are a little noisier. I need to add 2 of the S8 omnis very shortly. They are very quiet as well. The noisy ones you may need to use a noise gate on and I try to not have to do that. I also have an 50th anniversary SM58 vocal mic in a nice silver finish, but it is my least fav vocal mic. I also have 2 of the AKG C-3000 large diaphragm mics I can also use in place of the Rode’s or as a vocal mic. I have thought about the vocal Neumann 104 or 105 ($700), but I did not think it was a meaningful improvement over the Senn e945 for the money.
I would add that I have seen the late Mr. Sinatra use an SM 58, and even some affordable Omni’s in videos and also some AKG handhelds, but I know that in the Capitol Studio he had his own U-47/48 which is a spectacular mic ($4200) . Or even an U87 at $3300. These are all for folks who make money doing this. The late Andy Williams used a SM-58 in his concert at Royal Albert Hall decades ago. I have the video of it. Diana Krall uses the U-47 at Capitol now.
All nice, very affordable mics.