Why an AC Power Cord cannot make a difference

[somebodyelse]

Ok - I was hoping you could explain it without the Elliot paper.

The current only rushes in in some wine wave fashion.
I suppose if one flicks the switch to on, and they are at the top of the sine wave, then there might be some inrush.
But the transformer also has some inductance so whether the power cord is 1 ohm or 0.001 million-ohm, the rushing in of the current is not likely to be like a short that trips the breaker.

If you're looking at Figure 4, that's steady state after inrush has finished. Current only flows when the voltage from the transformer is higher than the voltage in the capacitors, so only a fraction of the sine wave period. Figure 3 shows the different currents and voltages in different bits of the PSU.

The other 'pulses' people bring up are possible ringing as the diodes switch from conducting to non-conducting or vice versa. That's the subject of a whole other Elliot article, more complicated than the first: https://sound-au.com/articles/psu-snubber.htm. Conclusion: it's usually a non-issue.

 

[watchnerd]

Wait, maybe it's about acoustic vibrations.
A cable between raisers looks just like a guitar string. So you need to be concerned about distance between raisers and cable tension.
Cable raisers are a great way to encourage vibrations.

Yes, I was figuring it was acoustic vibration, not electromagnetic wavelengths.

So, really, they should be suspended, not risen.

 

[Holmz]

If you're looking at Figure 4, that's steady state after inrush has finished. Current only flows when the voltage from the transformer is higher than the voltage in the capacitors, so only a fraction of the sine wave period.

Ok - so some harmonic of 120 Hz.

Figure 3 shows the different currents and voltages in different bits of the PSU.

There are minor (< a factor of 2) differences in inrush current for various sizes of capacitors in the Elliott link.

The other 'pulses' people bring up are possible ringing as the diodes switch from conducting to non-conducting or vice versa. That's the subject of a whole other Elliot article, more complicated than the first: https://sound-au.com/articles/psu-snubber.htm. Conclusion: it's usually a non-issue.

While I agree with the conclusion, to actually prove it… then one would need to show something.
- It could be the voltage at the rails…
- or it could be current through the cord-A versus cord-B.

One would need some material that demands current and using that same track for cord A vs B, and show a difference.

 

[watchnerd]

It has arrived.

I'm prepared to reach audio nirvana.

 

[PristineSound]

This is what I use in the US. Tripp Lite locking power cord. ". . .comes with a lifetime warranty. It’s manufactured in compliance with strict RoHS specifications" and UL compliant.

The locking ensures the power cable doesn't accidentally fall off. However, please note that the locking mechanism locks on the ground, so if you are using any older electronics without ground or floating ground design, this will not work.

And, yes, it does unveil the airy, sonic highs and chesty lows. . .even more so that anything Ted Denney can come up with.

https://www.connection.com/product/tripp-lite-computer-power-cord-nema-5-15p-to-locking-c13-heavy-duty-15a-125v-14-awg-2-ft.-black/p007-l02/36206351

 

[mhardy6647]

It has arrived.

I'm prepared to reach audio nirvana.

View attachment 451865View attachment 451866

I mean... there are good hospitals and not-so-good hospitals, you know?
(Sort of) Like that old joke:

Q: What do you call the person who graduates last in their class in medical school?
A: "Doctor".