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[Mike Sokol]

I have found that plugging various home audio components such as CD-players, preamps, amplifiers and the like into different wall receptacles can create all sorts of ground-loop induced hum. And because many (or most) home audio is unbalanced, there's no simple way to do a pin-1 lift to stop these ground loop currents and the hum they create. I've also been able to demonstrate that this ground-loop induced hum can be varied by the amount of current draw from the amplifier(s). So you might not hear any hum when there's no music, but pull a few hundred watts during a big bass note in a song, and all of a sudden you have a 60-Hz modulation hum in your subwoofers during that note. I found this in a pretty exotic home theater system that had "fuzzy bass" and traced the problem back to a copper coax SPDIF cable between a $3,000 CD player and an $8,000 preamp. It wasn't  the fault of the inexpensive copper SPDIF cable since the actual ground loop would have happened due to the shield of any interconnecting piece of copper. But when we simply swapped in a piece of TosLink cable that cost less than $5, all the problems went away and the bass sounded perfect. Now I'm pretty sure this wasn't some sort of jitter effect in the SPDIF stream, but was actually caused by ground loop current inside the preamp once the signal was converted to analog.

What this means is that nearly ANY change in the AC power and audio signal path of a home listening system can make some sort of difference in the sound. There's just so many interconnecting paths between all the different pieces of gear, many with potential for shield currents in unbalanced audio.

[Jonathan Johnson]

What this means is that nearly ANY change in the AC power and audio signal path of a home listening system can make some sort of difference in the sound. There's just so many interconnecting paths between all the different pieces of gear, many with potential for shield currents in unbalanced audio.

When something can be explained by science, magic, or religion, science usually loses.

[frank kayser]

The law provides for something called "puffing" like "this is the best car for the money" when it is a POS.  At what point does puffing become a lie? 

[Keith Broughton]

The law provides for something called "puffing" like "this is the best car for the money" when it is a POS.  At what point does puffing become a lie?

While advertisers inflate claims I think, as consumers, we need to pay attention to the language.
An example would be, "best fuel economy in it's class" You have to ask the question... what is the class?
Another is "one of the best xyz you can buy" That does not mean it IS the best but in a group of best. Meaningless.
Others are "get's up to x mile per gallon" or "may include" or "clinically proven"one of my favs"4 out of 5 doctors recommend" may be statistics on only 5 doctors!
Advertisers are there to get you to buy something, not to do you any favours, and we must always view their claims with a jaundiced eye.
In the end, if people want to part with their hard earned cash on total bull shit items, so be it.

[Kevin Graf]

I have found that plugging various home audio components such as CD-players, preamps, amplifiers and the like into different wall receptacles can create all sorts of ground-loop induced hum. .................................. I've also been able to demonstrate that this ground-loop induced hum can be varied by the amount of current draw from the amplifier(s). So you might not hear any hum when there's no music, but pull a few hundred watts during a big bass note in a song, and all of a sudden you have a 60-Hz modulation hum in your subwoofers during that note................................................................................
What this means is that nearly ANY change in the AC power and audio signal path of a home listening system can make some sort of difference in the sound. There's just so many interconnecting paths between all the different pieces of gear, many with potential for shield currents in unbalanced audio.

That may be a Neutral/Safety Ground swap rather that Common Impedance Coupling noise. One of the chassis's potential must be changing with changing loads.

* * * * * * * * * * * * * * * * * * *
Unbalanced chassis connections should be tested with a John Windt "Hummer Tester" but they never are.

* * * * * * * * * * * * * * * * * * *
Long unbalanced interconnects should have a heavy braided shield (equal to 14AWG) to reduce Common Impedance Coupling noise.

[Mike Sokol]

That may be a Neutral/Safety Ground swap rather that Common Impedance Coupling noise. One of the chassis's potential must be changing with changing loads.

* * * * * * * * * * * * * * * * * * *
Unbalanced chassis connections should be tested with a John Windt "Hummer Tester" but they never are.

* * * * * * * * * * * * * * * * * * *
Long unbalanced interconnects should have a heavy braided shield (equal to 14AWG) to reduce Common Impedance Coupling noise.

All true. But selling them an expensive power cable is much more lucrative.

[Michael Lascuola]

Some of Caelin Gabrie's statements:

...

...

His closing tag is the most useful:

 "NOT EVERYTHING THAT CAN BE COUNTED COUNTS, AND NOT EVERYTHING THAT COUNTS CAN BE COUNTED."
- ALBERT EINSTEIN.

And, even that appears incorrect 

https://quoteinvestigator.com/2010/05/26/everything-counts-einstein/

[ProSoundWeb Community]