Ars prepares to put “audiophile” Ethernet cables to the test in Las Vegas

[Jud]

I'll have to refer back the paper but nothing is mentioned about a clock divider.

 

The point not to be missed are a few. Ethernet only works because it is well isolated. It does a great job at noise rejection. No one can hear 25Mhz (or higher) and no one, outside of mere conjecture, has proven in any way, shape, or form, that it negatively impacts what happens on the USB buss.

 

 

The ESS SABRE chips do sample rate conversion to somewhere in the 40-44.1MHz region before conversion to analog, IIRC. If you were relying on the 25MHz rate as an assurance that no interaction could possibly occur.... (Not saying it would, of course - I have no idea, as I freely admit.)

[plissken]

It may be we are oversimplifying this. If your Ethernet connection happens to be over a HDMI

 

If you're using HDMI for a audiophile setup we need to have a talk

 

Now, down at the fine edge of possible, but unknown exactly how (im)probable, you have things like UTP emitting RFI, acting as an antenna, conducting electrical noise from the switch, etc.

 

The T.I. paper speaks to the difference in the PHY getting a clean signal and where that becomes problematic with 10G and up. So the onus looks like it's is placed now on the Ethernet cable itself to prevent alien crosstalk at those speeds. And its only a issue on transmit. As I showed in the video it's intermittent. And the higher you go in speed the shorter the transmit period.

 

If you aren't transmitting then there is nominal voltage on the line. Also SNR is variable. It's based on the length of the run.

 

BTW I'm in agreement that if you can go Optical. I think you can do just as well with properly configured wireless.

 

And all of that is an attempt to find a reason why Ethernet cables have sounded different to some folks.

 

Until these 'Some Folks' sit down in a blind manner for evaluation I personally have to treat it as conjecture. There is so much I would want to know and see about their setup. I wish one was local to me. I have all the equipment needed to run and properly terminate CAT5/6 cabling.

 

And unfortunately, it may turn out that the differences are not measurable at all - which makes it very possible they are not 'objectively real'.

 

Agreed.

[plissken]

The ESS SABRE chips do sample rate conversion to somewhere in the 40-44.1MHz region before conversion to analog, IIRC. If you were relying on the 25MHz rate as an assurance that no interaction could possibly occur.... (Not saying it would, of course - I have no idea, as I freely admit.)

 

40MHz and 25MHz aren't going to interfere with each other. This is the basis that FM radio works on. Now if you do hear bleed over on your radio it's because a station has modulated into the frequency of another that that's a huge no no.

 

What happens most of the time is you are picking up two distant stations on same band which makes perfect sense in that scenario.

[Teresa]

+1.

 

It's back to the most basic subjectivist / objectivist argument, one I've been tired of since the tube-transistor transition in the 50s. The pattern runs pretty similar: a change in technology; measurements of known distortions are taken and shown to be much less, and lauded—yet, to some, there is more distortion. Finally, new distortions are "discovered", along with a means of measuring them, and most (but amazingly, not all) of the early deniers will accept the problems associated with the new technology. Audio is pretty subtle; at some point, all of the possible temporal, dynamic, frequency, etc. based elements will all be understood enough so that they can indeed be measured and objectified, and this argument will fade into history. (I doubt it though...)

 

Great post! Yes, since the beginning audiophiles have reported the problems they hear and objectivists deny, deny, deny.

 

In the case of early transistor components they were hitting us over the heads with measurements proving how superior transistors were compared to tubes. Yet, early transistor amps sounded like crap. The objectivists didn’t admit they were crap until a few lone engineers thinking outside the box discovered TIM (Transient Intermodulation Distortion).

 

Once the distortion was discovered, low and behold those very same objectivists who screamed to the world that transistors were perfect now could hear the distortion.

 

In the 1980’s they claimed CDs were perfect, declaring those who preferred LPs or analog tape were accustomed to analog distortions that were now gone with CD. And that the ambiance and warmth of analog formats was a distortion and the cold, dry, strident sound of early CD playback equipment was what music really sounded like. That is until the invention of high resolution PCM and DSD which restored the analog-like ambiance and warmth of analog formats and live acoustic music.

 

Which is why I believe that objectivists either refuse to hear what they cannot measure or don't believe their own ears. Instead they ignore real audio advances by using the tool that makes everything under the sun sound the same: DBTs. AB and ABX tests either sighted or blind don't work as our brain defeats their purpose due to cognitive bias and listener fatigue.

 

• Cognitive bias - your brain will fill in missing information thus making both sound the same on repeated listening.
  
• Listener Fatigue - switch back and forth too much and both will sound like crap.
  

 

The only way I know to determine differences (if they exist) and which one sounds the best is long term listening over several weeks with a wide variety of music. My results apply only to me. Everyone hears differently and enjoys music differently, thus each person will have to listen for themselves and make sure they get a money-back satisfaction guarantee.

 

On the other hand DBTs work in the medical field as the human subjects don't have to make any decisions whatsoever. The subjects either are given the real medicine or a sugar pill. Those who get well taking the sugar pill do so as unconsciously their believe the medicine is real thus their antibodies manage to kill the disease, this is known as the placebo effect. If considerably more people get well with the new drug than with the sugar pill, the drug is considered effective. None of our five senses come into play in this type of test.

 

---

 

I stumbled into this thread because I didn't know what ethernet was and if I need a cable for it. Turns out I don't need ethernet. This thread was interesting at first but has turned into a train wreck.

 

I firmly believe it is rude to comment on something one has not heard in their system, thus I have no comment pro or con concerning AudioQuest's Vodka Ethernet cable.

 

However, I wonder how many people posting here are going to try the $250 AudioQuest Vodka Ethernet cable if they pass the ARS test? Personally, they are way out of my price range.

[Paul R]

Until these 'Some Folks' sit down in a blind manner for evaluation I personally have to treat it as conjecture. There is so much I would want to know and see about their setup. I wish one was local to me. I have all the equipment needed to run and properly terminate CAT5/6 cabling.

 

But see, there is the rub. They have perfectly reasonable and in many cases - reliable - observations. To dismiss those observations out of hand is - well - less than scientific, reasonable, or even good manners.

 

There is conjecture of course, but it is - or should be - about the reasons for the observed behavior. Not about the observations themselves.

 

That is, at least in part, because turning that conjecture into experimental evidence is neither easy or in-expensive. Even if you happened to be a redneck engineer able to use makeshift experimental materials. (grin)

 

-Paul

[MarkS]

In my experience, everything matters, and I mean everything (down to the wall socket). If things like cables didn't matter, then a file streamed from Tidal would sound the same as that file "streamed" from my local nas drive. But it doesn't and is not even close.

 

That said, I recently replaced standard Ethernet cable with a length of Audioquest Cinammon and couldn't hear a difference

[Paul R]

If you're using HDMI for a audiophile setup we need to have a talk

 

Actually, the video system can playback even the quad rate DSD music, and sound pretty good. Plenty good enough for casual listening.

 

But the HDMI connections do put a bugger load of noise on the line, and addressing that brings a distinct improvement, even while watching videos.

 

-Paul

[Teresa]

Anyone else find that much of this and other recent threads are like playing one of these over and over again? Just asking...

[ATTACH=CONFIG]19960[/ATTACH]

 

Yes!

[mmerrill99]

The degree of arrogance, technical ignorance & inability to read technical documents displayed here is mind boggling

Just one example from the TI document being continually referenced here about the 25MHz clock

"For 1000 Mbps operation, the Master PHY uses the internal 125 MHz clock generated from the CLOCK_IN clock to transmit data on the wire. The Slave PHY uses the clock recovered from the link partner’s transmission as the transmit clock for all four pairs."

 

@plissken Even if it was 25MHz, do you even know how many harmonics of this fundamental are required to generate a reasonable square wave (you know a digital signal is a square wave pulse on an electrical wire, don't you?) So have a guess about the number of harmonics required & then tell us what bandwidth this represents.

[mmerrill99]

40MHz and 25MHz aren't going to interfere with each other. This is the basis that FM radio works on. Now if you do hear bleed over on your radio it's because a station has modulated into the frequency of another that that's a huge no no.

 

What happens most of the time is you are picking up two distant stations on same band which makes perfect sense in that scenario.

Oh dear!! We now have pronouncements about multiple clocks not interfering with one another - fire all those engineers that deal with these issues on a daily basis, we don't need them!!

 

At this stage I'm pretty sure that he just plucks such uninformed statements out of his back pocket to defend some technical faux pas he has just made.

[mmerrill99]

Actually, the video system can playback even the quad rate DSD music, and sound pretty good. Plenty good enough for casual listening.

 

But the HDMI connections do put a bugger load of noise on the line, and addressing that brings a distinct improvement, even while watching videos.

 

-Paul

Oh, dear - that wouldn't be RFI noise that is above audibility (in the Mhz range perhaps?), now would it? How could this possibly be audible? Maybe you should tell plissken of your "anecdotal experiences"?

[mmerrill99]

Just re-iterating something Jriver posted earlier in this thread "It's now became, in my opinion, a place where grossly inaccurate information is commonly passed from person to person without regard to the basics of computing."

 

What we have here is an example of grossly inaccurate information being posted by plissken (although he's oblivious to his lack of knowledge) & being argued by him as being some form of "knowledge".

 

I don't mind him doubting whether Ethernet cables can be audibly different (I wonder the same thing) but his technical arguments are pathetically uninformed & incorrect at the electrical & at the system-wide level. His narrow perspective is typical of someone lacking in all but a cursory knowledge of what he is talking about.

[plissken]

The degree of arrogance, technical ignorance & inability to read technical documents displayed here is mind boggling

Just one example from the TI document being continually referenced here about the 25MHz clock

"For 1000 Mbps operation, the Master PHY uses the internal 125 MHz clock generated from the CLOCK_IN clock to transmit data on the wire. The Slave PHY uses the clock recovered from the link partner’s transmission as the transmit clock for all four pairs."

 

@plissken Even if it was 25MHz, do you even know how many harmonics of this fundamental are required to generate a reasonable square wave (you know a digital signal is a square wave pulse on an electrical wire, don't you?) So have a guess about the number of harmonics required & then tell us what bandwidth this represents.

 

I understand PWM as a lay person. Their is no evidence that the harmonics generated are reaching down into the 20Hz to 20Khz range how ever.

 

Plus these are heavily filtered devices just like switched mode supplies. It's a non issue.

 

I see zero evidence to support that this is audible.

 

You are searching for bogey men.

[plissken]

Oh dear!! We now have pronouncements about multiple clocks not interfering with one another - fire all those engineers that deal with these issues on a daily basis, we don't need them!!

 

At this stage I'm pretty sure that he just plucks such uninformed statements out of his back pocket to defend some technical faux pas he has just made.

 

These are filtered devices! They aren't going to interfere. The Engineering has already accounted for this. You need to explain how the 40Mhz on a USB connected DAC even interacts with the clock on the PHY.

[plissken]

Just re-iterating something Jriver posted earlier in this thread "It's now became, in my opinion, a place where grossly inaccurate information is commonly passed from person to person without regard to the basics of computing."

 

What we have here is an example of grossly inaccurate information being posted by plissken (although he's oblivious to his lack of knowledge) & being argued by him as being some form of "knowledge".

 

I don't mind him doubting whether Ethernet cables can be audibly different (I wonder the same thing) but his technical arguments are pathetically uninformed & incorrect at the electrical & at the system-wide level. His narrow perspective is typical of someone lacking in all but a cursory knowledge of what he is talking about.

 

Then POINT OUT WHERE I'M MISTAKEN.

 

Because intimating that a 125MHz master clock and it's harmonic's are of a signal strength down in the the even the 44Khz range is just astoundingly showing a lack of understanding that the engineers filter this stuff.

 

Amazing amount of stupidity.

[mmerrill99]

I understand PWM as a lay person. Their is no evidence that the harmonics generated are reaching down into the 20Hz to 20Khz range how ever.

You understand what as a lay person? Why would a square wave need harmonics in <20Khz to be adequately formed as a signal? You prove yet again that you are so far removed in understanding from what you are trying to talk about that it's impossible to bridge that gap - it's a chasm, I'm afraid.

 

Did you read & understand the TI paper you so often referenced for your 25MHz bandwidth?

 

Plus these are heavily filtered devices just like switched mode supplies. It's a non issue.

 

I see zero evidence to support that this is audible.

 

You are searching for bogey men.

Sure, why the use of terms like "zero evidence", "bogey men", etc. when all we are discussing are the technical possibilities which you continually trip yourself up on in your rush to deny any such possibilities? You either understand the technical logic & can argue about it on a technical level or you don't. You patently don't & this is why you make such blunders & resort to the above "zero evidence" "bogey men".

 

It's a technical discussion, not an assault on science - stop trying to pretend you know more than you do!

[mmerrill99]

These are filtered devices! They aren't going to interfere. The Engineering has already accounted for this. You need to explain how the 40Mhz on a USB connected DAC even interacts with the clock on the PHY.

Nope, you need to find this out for yourself as I see no benefit in me wasting my time with someone who has no desire to learn - who just wants to argue.

[mmerrill99]

Then POINT OUT WHERE I'M MISTAKEN.

 

Because intimating that a 125MHz master clock and it's harmonic's are of a signal strength down in the the even the 44Khz range is just astoundingly showing a lack of understanding that the engineers filter this stuff.

 

Amazing amount of stupidity.

This is just another demonstration of the huge chasm between what you think you know & what you actually do - it's there for all to read who have any technical knowledge. Please stop polluting the thread & "spreading such misinformation" as Jriver unknowingly said about your posts.

[firedog]

A great thread, I will give a synopsis:

 

"You're stupid!"

"No, you're stupid!"

[mmerrill99]

A great thread, I will give a synopsis:

 

"You're stupid!"

"No, you're stupid!"

I know - it's like a Christmas pantomime (0h, no you didn't - oh yes I did) but there is such a gross level of misinformation & wild technical statements being made that someone has to point these out to prevent what Jriver posted "spreading such misinformation".

Of course these types of discussions become boring for most but as Mayhem13 said "But if you really wanna be a lamb, just say yeah"

[Tony Lauck]

Oh dear!! We now have pronouncements about multiple clocks not interfering with one another - fire all those engineers that deal with these issues on a daily basis, we don't need them!!

 

At this stage I'm pretty sure that he just plucks such uninformed statements out of his back pocket to defend some technical faux pas he has just made.

 

In the case of those SABRE chips there are artifacts created as a result of the ASRC algorithms, That the ASRC is imperfect can be illustrated in the patent disclosure. See figure 17A and 17B and the related text from US7436333.

[Tony Lauck]

Oh, dear - that wouldn't be RFI noise that is above audibility (in the Mhz range perhaps?), now would it? How could this possibly be audible? Maybe you should tell plissken of your "anecdotal experiences"?

 

Alas, my powered Focal monitors are susceptible to RFI noise in the GHz range. This happens every time I receive a text message if I have forgotten to take my cell phone out of my pocket before entering my listening room.

 

is this really happening? This is definitely a blind test, what with the cell phone being in my pocket.

[mmerrill99]

In the case of those SABRE chips there are artifacts created as a result of the ASRC algorithms, That the ASRC is imperfect can be illustrated in the patent disclosure. See figure 17A and 17B and the related text from US7436333.

The interesting thing is that the audibly negative impact of the ASRC was being reported as "anecdotal evidence" by audiophiles after the Sabre DAC got into DIY hands & they did asynch Vs synch comparisons (turning off the ASRC)

 

But how could this be possible when buffering is involved?

[mmerrill99]

Alas, my powered Focal monitors are susceptible to RFI noise in the GHz range. This happens every time I receive a text message if I have forgotten to take my cell phone out of my pocket before entering my listening room.

 

is this really happening? This is definitely a blind test, what with the cell phone being in my pocket.

 

It's simple - broken engineering - it's everywhere (except in some people's mind - it's just so simple to fix that they must be too lazy to do it, I guess?)

[jriver]

A great thread, I will give a synopsis:

 

"You're stupid!"

"No, you're stupid!"

Hard to argue with that.