Very good AES presentation on inter connects and ground loops.

@audioman58 you have certainly wasted a lot of money on things that cannot have an impact, to OPs point. 

Fredrik222 you speak out of ignorance.

myself and many others in our audio club have tested many combinations 

Ethernet cables ,and usb cables ,linear power supplies all have audible improvements all well tested not knowing which were being tested.

myself owned a Audio store for a decade . I have  no idea what your audio system consists of but ,unless your system is of a higher quality you may not hear the improvements ,there are too many variables. I rebuilt Loudspeaker Xovers for a guy over $ 1600 and made a Very large improvement ,he was using $100 Belen interconnects and thought it was good from what he was told , you have to spend 

bare Minimum of $2k just for speaker cables and a pr of interconnects to hear  the nuances in the recordings and at much more $ monies there are cables much better still it all depends on your budget, this applies to everything from Electronics, to Loudspeakers . Synergy is very important ,your dac at minimum $2k to get anything respectable by Audiophile standards ,reference $6k and up. I have heard several hundred Audio systems a $25k system is a good starting audiophile system 

most have $50 k + system if realism and refinement is your goal. These are my opinions and viewpoints and having owned a Audio store can speak through experience and what others expect , the more experienced you are as a Audiophile 

the more you expect if your budget will allow for it.

Hello tvrgeek.  I wanted to get a look at your system to see where you are coming from.  No luck there.  There are some holes in your arguments.  But first, I read the paper and my interpretation is the author is for balanced connections.  He made the comment that SE, RCA connections should have gone away decades ago.  

I agree that older audio gear electrical and grounding methods needs to be looked at closely for both safety and S/N issues.  I can recall as a kid in the 1960s getting zapped when touching the metal frame of my grandfather's b&w TV.  Yes, I was  barefoot on a concrete floor.  It was a pretty strong shock.  Newer Tube gear made on the US and EU seem to be good and I think most top brand SS gear going back decades is good.  I stick to the well known brands after having bad experiences decades ago with newcomers or flash in the pan brands that were not so well made on the inside.  Caveat Emptor is always the case.

The author expounds a lot on house wiring.  I can agree with him.  I found in the late 1980's my ARC SP-6b could tolerate no dimmers in the house at all.  They all had to go.  My newer ARC gear years later I found, did a much better job at rejecting noise.  I wired in my own dedicated power lines for my stereo.  (I'm a licensed professional engineer but also am experienced at wiring houses.)  One thing that annoyed me is whoever wired my house mixed the White wires and ground wires on the ground busses.  I know it doesn't matter but I like things looking nice and neat.  I cleaned them up as best I could.  

The author also made a very good point that everyone should take note:  Don't operate your audio gear on a separate ground rod.  You can have multiple ground rods but they must all be tied together as one, back to the main breaker panel.  

Redbook CDs have limitations as compared to the master tape.  That doesn't mean that converting to hi res is pointless.  It's more about the filters and the skill of the engineer than the technical matters.  CDs have less limitations than LP's.  And yet Vinyl sounded better for many years.  I was convinced CDs were inferior until I got my new DAC and CD Transport a couple of years ago.  That opened my eyes to digital music.  Today I can enjoy both sources equally.  They each have their own characteristics but it is more of a flavor rather than a deficit or advantage.  Vinyl was considered an inferior source well into the 1980s.  Ironically, CDs seemed to elevate the status of vinyl back in the 80s and 90s.  What was better than vinyl, you ask?  R2R master tapes.  The hardcore audiophiles back in the day would listen to nothing else.  I think vinyl sounds great.  Shows what I know.

Comparing how things sound at a hifi shop is a no go.  Even the most high end boutique stores have one goal:  Move product.  They don't have the time or interest to dial a system in to within a 1/4" when everything is likely to me moved the next day or next week.  Even at my favorite audio store in Michigan decades ago, Harry would pull the Magenpans away from the wall and roughly position them if you wanted to hear that system.  It always sounded great but imagine if the room didn't have all the other gear stacked up in there and the panels were dialed in precise.  Secondly, audio stores have dirty power and lots of EMI from lights, other businesses and all the other gear operating in the room/rooms.  I begged the owner of a store to just buy a couple of FMCs to isolate his ethernet optically.  He is demonstrating DCS and Chord DACs.  They sound so lackluster when he is streaming with them and I know it is due to noisy ethernet.  Sure, high end gear should not be affected by noise coming in.  And apples shouldn't start rotting when they fall off the tree.  In the real world we have to isolate and protect our precious, tiny little signals from our tonearms, our streamers and our preamps from the harsh and cruel disruptors of RFI, EMI and even mechanical vibration.  

Tony,

I stared this thread as there is a lot of incorrect perceptions on the subject.

I agree SE was never the best answer, but he is talking about the physics, not if you need it.  My point is, SE is probably just fine for a home system. Listen to see if it is, don't assume what is needed for 100 foot studio runs is also needed for 3 feet.  Fix real problems you find in your system with the help of information from the actual field experts rather than the fad of what You-Tubers and audio parlors can sell you.  

Yes, we have electrical building codes for a reason. Follow them. Yes, a lot of old equipment did not have safety grounds and the leakage could give you a tingle. Easy to fix. I like the JDS answer to use AC wall wart transformers.  No ground loop and zero risk of fault to mains. Any competent mains powered unit will deal with ground isolation internally. It is not hard or expensive. Even I can. No excuse. 

I only had one piece of equipment that had line induced issues. A Parasound amp so I dumped it as being incompetently designed. It also sounded like garbage. Not like the old 1200's. I do run a DC blocker as it filters DC added within my house by cheap devices not supplied by the power company.   Real problem. Real fix. 

One  store I visit does play all kinds of games moving speakers within 1/4 inch.  So what! I move my head more than that. If you have to hold your head that still, it is a useless system. ( Kef Meta's?)   On the other hand the big store here has the wall of speakers driven through switching and a mid-range class D amp which are almost useless other than to eliminate the worst of the bad. They will take a pair down to a better room to their credit but that leaves you with no comparison and within seconds your brain remaps so still not a very valid audition. End result is, you can pick something to take home over the weekend and give areal listen. 

R2R, I think you mean Reel to Reel low generation dups onto quarter track a few studios issued? All analog. ( In todays jargon, it is assumed to be a ladder DAC)  Yea they were good but I only had a couple. Way out of my price range and were only available mail order. I had a 10 inch Teac. Like vinyl, they degraded with every play.  I went for the direct-to-disk live performance route where I could afford them.  And don't tell me MoodyBlues analog mastering quality is HALF of Redbook.  Things got better with the second generation SONY digital mastering ,16 bit, then 18 and on. Yea, my CATs CD was mastered in 14 bits. Most early Deuchas Gramaphone was. No wonder the best vinyl sounded better.  40 years later,  newest studio work can be very very good. Unfortunately most of my music collection predates digital recording and was re-mastered and processed digitally for CD release. 

If your "audiophile Ethernet" sounds better to you, have fun.  It is your perception in your system that matters to you.  I  am not a fan of made up problems that may exist in theory, but not in the real world. If network noise is causing you a problem, you need to find the faulty devices.  We don't need audiophile grade switches for 10G, live fire, nuclear, life threat, and can bounce 100% reliable data around the world on the Sonnet ring and satellites.  If you can't within your house, you got a problem. If you can identify the demo of a DAC being lackluster due to Ethernet noise, you should get some University to study your clairvoyance.  I am not saying you did not hear a lack-luster DAC. You heard it, I did not. I suggest your reasoning is less than a guess.  It could well be you are not used to a clean reproduction from a really good DAC?   Or maybe it was Cambridge/Rotel/Arcam amp with half the power supply reserves needed not the DAC?  Was the stream actually high quality? Most is not. 

Setup, room, treatments, yea, duh!  Differences almost as large as the speakers. 

You missed my point on if high end gear is effected by noise; digital, ground loops, power, then yes, I blame the OEM.  NO excuse.  Apples will start rotting as that is the environment they live in, just as dirty power is the environment.  We understand the environment of apples and learned to pick them before they fall off. Just as decent engineers know how to handle system noise. 

If you play vinyl, then isolating your player in a sealed box does wonders. Put your RIAA preamp in the base of the table close to the arm and you won't have any RFI exposure. That way you can maintain the balanced signal from the cartridge until you have provided enough gain that a couple feet of coax is fine.