Why an AC Power Cord cannot make a difference

[watchnerd]

Well then … your intellectually curiosity needs work.

One could find someone to attach leads to the rails, and have a voltage divider circuit to get it down to the ADC level.

But I did word the way I did, in order to let people without basic electronics skills know it is not 100% safe.

I haven’t etched a circuit board since undergraduate years.

I’ve repaired my ReVox tape decks but amps scare me

 

[Holmz]

I haven’t etched a circuit board since undergraduate years.

I’ve repaired my ReVox tape decks but amps scare me

Ok but which amp?

• If it is a 100W job they are only ~28V.
• If it is a class-D or other super high feedback amp, then even if the power was ripping it would be unlikely to sneak through.
• And each amp design has a power supply section, so a cord that improves one brand may not do anything on a different brand with a better designed power supply.

 

[egellings]

Ok but which amp?

• If it is a 100W job they are only ~28V.
• If it is a class-D or other super high feedback amp, then even if the power was ripping it would be unlikely to sneak through.
• And each amp design has a power supply section, so a cord that improves one brand may not do anything on a different brand with a better designed power supply.

They all have the dangerous line voltage in them.

 

[watchnerd]

Ok but which amp?

• If it is a 100W job they are only ~28V.
• If it is a class-D or other super high feedback amp, then even if the power was ripping it would be unlikely to sneak through.
• And each amp design has a power supply section, so a cord that improves one brand may not do anything on a different brand with a better designed power supply.

Luxman L-590AXII

 

[Cbdb2]

EM radiation is easy to measure, you do not need to visit EMC lab. But it will be labeled as unimportant, here at ASR.

Testing radiation of 3 AC power cords (what are the ASR tests about??)

We could see several power cords tests here at ASR and frankly, I have to ask what are the tests like this one https://www.audiosciencereview.com/forum/index.php?threads/audioquest-nrg-x3-review-ac-power-cord.32257/ What is important? In my opinion, the aim of a good power cord is to minimize...

www.audiosciencereview.com

Thats half a test. Show us how little of that EM radiated by the power cord gets in to a systems coax interconnect thats a couple inches away.

 

[watchnerd]

Just think of the epic inscription on the gravestone: "He did it for the team and for science. In loving memory, your ASR buddies"

Gravestone?

More like an etching on the urn of smoldering ashes

 

[Cbdb2]

The arguments I have heard are that the power resistance cord lets the power in faster.
Which charges the amp faster/better.

The 6' cord at the end of 300' of cable that runs to the transformer?
Faster is not necessarily better. A/B amps charge with current pulses, with faster rise time you get more EM radiated inside the amp.

 

[Devnull]

They all have the dangerous line voltage in them.

It's not the voltage it's the current that's dangerous. You shouldn't have anything to worry about because your 500 dollar audiophile fuse after an appropriate amount of burn in time will protect you

 

[Holmz]

The 6' cord at the end of 300' of cable that runs to the transformer?
Faster is not necessarily better. A/B amps charge with current pulses,

Can you describe those pulses?
I am envision a photon torpedo on some SciFi show, rather than a factual thing on a HiFi show.

with faster rise time you get more EM radiated inside the amp.

How can the rise time faster?
And it is voltage rise rise time or current rise time you are thinking of?

 

[Holmz]

They all have the dangerous line voltage in them.

I can feel the hackles on the back of my neck, and the hairs on my arms standing on end just thinking about it.
I was going to-n-fro, but I am only down with Fro.

 

[mhardy6647]

Interestingly, one common specification for backup/emergency power generators is total harmonic distortion.
You can look it up!

 

[middlemarch]

You guys can drag this out for 450 messages? Must not be a lot going on in the real world...

 

[Gibsonian]

I do find it amazing seemingly sane individuals will spend tens of thousands of dollars for copper or silver wire with connectors on it. It mystifies me I must admit

 

[watchnerd]

You guys can drag this out for 450 messages? Must not be a lot going on in the real world...

It's a healthy mental break from tube rolling

 

[BeeKay]

It's a healthy mental break from tube rolling

And us discussing the optimal height of cable raisers. Which we should continue!

 

[watchnerd]

And us discussing the optimal height of cable raisers. Which we should continue!

We've been completely ignoring that AC cords should be raised, too, according to some experts in the subject of cable raising.

Based on my calculation of the wavelength of 60 Hz AC in North America (5.57 meters) then the AC cord should be raised half of that to avoid phase interference from floor reflections.

5.57 / 2 = 2.785 meters

Probably better to suspend the AC cords from the ceiling.

 

[Speedskater]

That's for the speed of sound.
For AC power it's 6 kilometers.

 

[Speedskater]

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.

 

[Cbdb2]

Can you describe those pulses?
I am envision a photon torpedo on some SciFi show, rather than a factual thing on a HiFi show.


How can the rise time faster?
And it is voltage rise rise time or current rise time you are thinking of?

Current pulses /rise time. This explains things. Diagram half way down.

Linear Power Supply Design

ESP - The Audio Pages. Linear power supply design information - Learn how to design your own high performance amplifier power supply.

sound-au.com

 

[Holmz]

Current pulses /rise time. This explains things. Diagram half way down.

Linear Power Supply Design

ESP - The Audio Pages. Linear power supply design information - Learn how to design your own high performance amplifier power supply.

sound-au.com

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.