Electromagnetic Interference in Speaker Cables? (video)

[Helicopter]

Hi @amirm

In one of your videos you mentioned an AC power transformer near analogue cables can measurably interfere with audio band.

And you showed it here (includes timestamp):

And you mentioned our threshold for hearing is very high at low frequency noise and the noise levels are low anyway.

But does the same AC transformer wand measurement also show changes over unshielded ethernet cable? For something like a Matrix Audio Element DAC with ethernet input?

Again, I'm not concerned about audibility but do you get a ~15dB increase in noise like you did with the generic (shielded) RCA interconnect?

Speaker cables have much more current than line level so it is not an issue with them.

 

[amirm]

But does the same AC transformer wand measurement also show changes over unshielded ethernet cable?

Probably so. I have one test where I put an AC mains next to Ethernet cable and managed to show tiny difference. Plan to do a video on that.

 

[Music1969]

Probably so. I have one test where I put an AC mains next to Ethernet cable and managed to show tiny difference. Plan to do a video on that.

Nice, thanks!

If you had a shielded ethernet cable to compare with unshielded that would be cool too.

Although shielded ethernet cables can actually cause more issues (ground loop) I heard, so one would have to be careful.

 

[Music1969]

Speaker cables have much more current than line level so it is not an issue with them.

Noted, I wasn't asking about speaker cables though.

 

[redstang]

As i said more then the <10µA test you made a video about.

I mean there is not only the power lines going to the HiFi setup in my house has more tings that consume current and emit magnetic fields
and people seem to use this:

View attachment 114433


View attachment 114436




The current of a view micro amp will produce a weak magnetic field (mostly at the beginning of the cable and almost non at the end)
most of this will cancel out.
So the effect of an magnetic field from a view micro amps is for me negligible! (since "normal devices" can uses 10s of amps)
A view microamps into the speaker cable is not the same thing! (as a view microamps into a power cabel next to a speaker cable)

You can chose to acknowledge that the initial test had significant flaws since your current was like one millionth of a typical current
Or you can chose to nitpick because technically there was current even if its only one millionth (of an transformer inrush current or something)

But then its funny to say my assumption of a view kW load is untypical while insisting your µW test from the video was valid and conclusive.

Choseing to insist the test was valid with µAs sound like a Danny thing to me.


Your right, only proofing my point...
I'm waiting for this simple calculations showing the inductive coupling

Yeah, Amir's test wasn't great, and his second test with the power cord being used was still insufficient. To be relevant he would need to run the power and speaker wires in parallel for several feet, as well has have it be the power cord for a component that was active. Now, I would still expect the effect to be minimal to non-existent, but if you're going to bother doing a test, it should be a real world example. And then you go myth-busters style and amp the circumstances WAY WAY up to see at what point, if ever, you can get any audible effect.

I would also like to see measurements of simply running left, right, and center channel cables next to each other for say 15 feet, as LOTS of people (including me) are running several wires from say an equipment closet to their speakers via channels like you show in the pics.

 

[Music1969]

**Aside, What are the arguments some audiophiles make as to why blind testing is invalid? I am sure there are threads here that address it and I want to read up.

One that comes up is that the stress of having to make a decision in blind testing causes people to get confused and guess.

And that normal listening doesn't involve this particular type of stress on brain.

Don't shoot - you asked what are some arguments that come up and this is one

 

[Emlin]

One that comes up is that the stress of having to make a decision in blind testing causes people to get confused and guess.

And that normal listening doesn't involve this particular type of stress on brain.

Don't shoot - you asked what are some arguments that come up and this is one

Although their wives would have passed the test from the kitchen. Three streets away at her mother's house.

 

[redstang]

One that comes up is that the stress of having to make a decision in blind testing causes people to get confused and guess.

And that normal listening doesn't involve this particular type of stress on brain.

Don't shoot - you asked what are some arguments that come up and this is one

I've seen so many crazy anti-blind test arguments. Yep, you have the stress angle. Then you have the simple statement that a blind test simply isn't a normal listening situation - that when you listen over the course of longer times you can tell that things sound different/better after changing cables. Another huge one is that if you can't hear a difference, then your system isn't "resolving" enough (i.e. expensive enough). Then there's also the one where "the entire system needs to acclimate" to the cables and settle in. Sort of a burn-in type of argument that somehow it takes some time (hours to days) for the amplifier and cables to come into a harmonious relationship, so fast switching cables doesn't work. It always amazes me the theories people come up with. I think that's part of the reason why this debate can be so entertaining.

 

[Music1969]

Although their wives would have passed the test from the kitchen. Three streets away at her mother's house.

They're not under the stress of the test though !!

 

[amirm]

To be relevant he would need to run the power and speaker wires in parallel for several feet,

Several feet? Where would I read the high-end speaker wire manufacturers saying that the scenario for their cables?

Now, I would still expect the effect to be minimal to non-existent, but if you're going to bother doing a test, it should be a real world example.

There is nothing real-world about that. AC wire coming out of an amp has no tendency to run parallel to speaker wire with zero distance for several feet. And if that is the scenario, then don't run it several feet that way.

Let's remember that I am trying to debunk Danny's test where the exposure was the diameter of the coils which was just an inch or two, not several feet.

 

[Emlin]

They're not under the stress of the test though !!

You think that having to live with a wanker like that is not stress enough?

 

[Music1969]

You think that having to live with a wanker like that is not stress enough?

hilalrious (in case people misunderstood, he's talking about the husband here not the wife).

For the double blind tests that @amirm has said he passed due to his training, I wonder how he would go if he had all his friends like Audioquest marketing team, John Darko, Stereophile writers, Rob Watts , Ted Smith, all in the same room watching him do the test.

That's not a dig at Amir but it is presenting a new pressure/stress that perhaps Amir didn't have when he did pass previous test...

It doens't change Amir's previous double blind testing results !! Those are 100% valid OF COURSE !! But it would be interesting to see if this new stress/pressure changes his performance.

 

[Emlin]

hilalrious (in case people misunderstood, he's talking about the husband here not the wife).

For the double blind tests that @amirm has said he passed due to his training, I wonder how he would go if he had all his friends like Audioquest marketing team, John Darko, Stereophile writers, Rob Watts , Ted Smith, all in the same room watching him do the test.

That's not a dig at Amir but it is presenting a new pressure/stress that perhaps Amir didn't have when he did pass previous test...

It doens't change Amir's previous double blind testing results !! Those are 100% valid OF COURSE !! But it would be interesting to see if this new stress/pressure changes his performance.

In the same way that I have 20:20 vision except when I undergo the stress of visiting the optician.

 

[Music1969]

The only stress is from themselves, when they become aware that their self-ascribed golden ear status is about to be debunked.

Noted but if we're going to objective, we should be objective all the way, not halfway. And there's no way to know how Amir would do in this kind of environment unless the test was conducted.

Which will never probably happen obviously.

 

[respice finem]

...the stress of having to make a decision in blind testing causes people to get confused and guess. ...normal listening doesn't involve this particular type of stress on brain.

While this is true, this "stress" is also there in a non-blind test, however eased by visual cues, which in turn can (and often will) be misleading. Whether blind or not, it can happen, I hear a difference, but can't really decide which version is better. And then, normal listening is not about comparing gear at all...
My personal conclusion: I'm aware of simply not hearing many drawbacks of my setup, but then hey, I'm neither a musician nor a mastering engineer, so maybe it is not that bad for me after all. And as an amateur, I don't really need to take the complicated way of a blind test (a bit hard to blind yourself in most cases), when for my humble case a "deaf test" (like reading a review on ASR) may suffice. A bit nihilistic, I know - but practical...

 

[respice finem]

In the same way that I have 20:20 vision except when I undergo the stress of visiting the optician.

A little afterthought: If a bit of stress makes me unable to tell the difference, then maybe that difference is not that big, after all?

 

[Music1969]

While this is true, this "stress" is also there in a non-blind test

Noted but we can't have a bunch of engineers trying to be pyschologists/psychiatrists/neuroscientists on this.

We either do the test or just leave it for experts in those fields to talk about how stresses vary and may affect results.

In my opinion.

 

[Hiten]

amateur posting :
two years back I made a CNC phono preamplifier and powersupply. I tested it as shown in below video

I put RCA input pins on 9-0-9V Transformer deliberately and made jumble of all wires gathered in a bunch above the power supply circuit. The interconnect wires were also long. I was hoping to hear some noise/hum. But it was silent. Given to understand that on scope the noise would have been picked up but even after close proximity of open circuits (No chassis/ground etc.) and wires and transformer it was silent with my ear close to my testing speakers (Creative 2.1).

pic of Phono preamp.

 

[Dzhaughn]

Look at Amir with that eyebrow and smile on the video image.

EDIT: You sure we can't lick live wire? I don't believe in measurements, I like to feel how many watts of power some of my stuff outputs..

Sure you can lick it. But the question is: Will it be audible?

 

[magicscreen]

I have the best speakers. The speaker cables go in the box and I cannot change them. So problem is solved, I cannot buy a replacement audiophile speaker cable. There is no temptation.