Fancy outlets on the computer side...

[One and a half]

18 minutes ago, gmgraves said:

Essentially, all the mains supply upgrades in the world are negated by the bottlenecks that occur down-stream in the components themselves.

Do you consider the interaction of AC pulsed currents due to rectification on the DC side causing problems, by that,  distortion of the sine wave?

[fas42]

On 3/5/2020 at 10:22 AM, mfaoro said:

Gmgraves, fas42: Are you asserting that improving wiring before the component does not make much difference since the wiring in the component is usually very limited in its capacities. 

 

It's not a question of where the wiring is - at any point in a system, whether a cable internal to a component, in a lead connecting components, or for a power cable going to the wall, if the design or quality or implementation is not good enough, then it may cause audible loss of SQ.

[gmgraves]

1 hour ago, One and a half said:

Do you consider the interaction of AC pulsed currents due to rectification on the DC side causing problems, by that,  distortion of the sine wave?

That might be possible, but keep in mind that in some systems the power transformer is fed a square wave, and in car radios, the power transformer is fed interrupted DC from the “vibrator”. IOW, I don’t think a slightly distorted sine wave on the primary side of the power supply will affect the DC output one iota. Now, it occurs to me that by a distorted sine wave, you might be talking about the amplifier output. The answer there is no.

[gmgraves]

17 hours ago, gmgraves said:

That might be possible, but keep in mind that in some systems the power transformer is fed a square wave, and in car radios, the power transformer is fed interrupted DC from the “vibrator”. IOW, I don’t think a slightly distorted sine wave on the primary side of the power supply will affect the DC output one iota. Now, it occurs to me that by a distorted sine wave, you might be talking about the amplifier output. The answer there is no.

When I mentioned car radios, I failed to make the distinction that I was talking about the old tube car radios from the 1950’s and early 1960’s. They took the 6 or 12 volt car battery voltage and “chopped it” into pulsed DC and the power transformer in these radios are not being fed by a sine wave, but by a DC voltage that is going from zero volts to the battery voltage and back to zero again. This is about as far from a sine wave as you can get. But I have looked at the DC B+ from these radios’ power supplies and they are as clean as the power supplies in any AC powered system.

[One and a half]

The paper attached to this post came from Raife Smith, downloaded and compiled into a pdf, before Polk audio decided to remove the whole she-bang years ago now.

The data i still relevant, where Dr. Raife Smith measures FFT, sine waves from different outlets, cables. There are differences relating to different outlets, some cables have notable lower noise figures, FFTs say so. Some spikes are still there, but the underlying crud is reduced quite a bit. The paper starts to get interesting pp40 onwards.

There's also FFT of speaker outputs and how different cables affect same. 

That doesn't happen with every amp, when I tried with my amp on Fluke 93 (IIRC) all was displayed was a single line at the fundamental tone frequency.

So there's something there, no need to be dismissive, keep an open mind.

 

 

Studies On Residential Power Line Noise.pdf

[Speedskater]

That paper is by the DarqueKnight, Raife Smith, Ph.D.

No one should take anything he wrote about hi-fi or AC power seriously.

[audiobomber]

1 hour ago, Speedskater said:

That paper is by the DarqueKnight, Raife Smith, Ph.D.

No one should take anything he wrote about hi-fi or AC power seriously.

Are you suggesting he falsified the graphs or information presented? 

 

Mr. DarqueKnight seems like an intelligent, credible and highly knowledgeable fellow to me. He handed Arny Krueger a drubbing in this thread like few I've ever seen: 

https://forum.polkaudio.com/discussion/104973/a-historical-overview-of-stereophonic-blind-testing

 

I had the local power authority test the power at one of the facilities I managed, as we were having a great deal of trouble with a large Variable Frequency Drive. The voltage spikes and grunge on the line shown by their sophisticated instrument was shocking.

 

It's well known in facilities management that dirty power leads to premature failure of lighting, motors, etc. These days, the number of switching power supplies, electronic ballasts, computers, etc, connected to the grid have added an immense amount of harmonics, EMI and RFI. I use power conditioners in my system for this reason, and hear improved SQ. I have not invested in after-market power cords, but audiophile fuses in my power amps did improve the sound. 

[Speedskater]

6 hours ago, audiobomber said:

Are you suggesting he falsified the graphs or information presented? 

No he didn't account for uncontrolled variables, and really didn't understand what he was measuring.

 

6 hours ago, audiobomber said:

Mr. DarqueKnight seems like an intelligent, credible and highly knowledgeable fellow to me.

When it comes to AC power, highly knowledgeable he is not.

 

6 hours ago, audiobomber said:

He handed Arny Krueger a drubbing in this thread like few I've ever seen: 

Arny Krueger (RIP) was in fact a highly knowledgeable engineer.  The DarqueKnight didn't do so well in other forums that dealt with facts and accuracy. 

[Don Hills]

Using a LPS to replace the SMPS in a computer seems to be a popular mod. But it ignores the elephant in the room - the SMPSes on the motherboard that supply the CPU and peripheral chips. They're much more intimately coupled to the internal circuitry.

(I agree that a LPS for the main supply can reduce noise fed back into the mains, although a good line filter will do that too.)
 

[sandyk]

31 minutes ago, Don Hills said:

Using a LPS to replace the SMPS in a computer seems to be a popular mod. But it ignores the elephant in the room - the SMPSes on the motherboard that supply the CPU and peripheral chips. They're much more intimately coupled to the internal circuitry.

(I agree that a LPS for the main supply can reduce noise fed back into the mains, although a good line filter will do that too.)
 

 

 The main beneficiaries of an internal LPSU are the SATA devices such as an Optical device and both OS SSD and Music storage SSDs, and a USB card where installed . Internal sound cards usually have a further improved power supply .

[One and a half]

19 hours ago, Speedskater said:

That paper is by the DarqueKnight, Raife Smith, Ph.D.

No one should take anything he wrote about hi-fi or AC power seriously.

For once, there's measurements of different power cables, sources, with actual readouts from a scope, and you dismiss because the author measured improperly, why , do you suspect the probe to be not the right sort or held at the wrong angle, or the orange lines too thick on the FFT?  

 

 

[DarqueKnight]

On 3/10/2020 at 5:50 PM, Speedskater said:

No he didn't account for uncontrolled variables, and really didn't understand what he was measuring.

 

When it comes to AC power, highly knowledgeable he is not.

 

Arny Krueger (RIP) was in fact a highly knowledgeable engineer.  The DarqueKnight didn't do so well in other forums that dealt with facts and accuracy. 

It would be helpful  if you would point out specific errors in my methodology and what you perceive to be misunderstandings on my part.

[One and a half]

58 minutes ago, DarqueKnight said:

It would be helpful  if you would point out specific errors in my methodology and what you perceive to be misunderstandings on my part.

Welcome to AS @DarqueKnight

[plissken]

On 3/6/2020 at 6:27 PM, One and a half said:

There's also FFT of speaker outputs and how different cables affect same. 

That doesn't happen with every amp

 

Probably should get an amp that filters it's input A/C. Hi Z cable can put some amps into oscillation .

[audiobomber]

On 3/14/2020 at 2:23 AM, DarqueKnight said:

It would be helpful  if you would point out specific errors in my methodology and what you perceive to be misunderstandings on my part.

Crickets.

[One and a half]

2 hours ago, audiobomber said:

Crickets.

Speaks volumes, don't it?

[Audiophile Neuroscience]

On 4/13/2020 at 2:47 PM, One and a half said:

Speaks volumes, don't it?

maybe @Speedskater didn't see @DarqueKnight post ?