WHF S&V hits rock bottom: now claiming USB cables have an effect on sound quality

[admin_exported]

So the world has moved on and now accepts that HDMI cables can't degrade a digital signal (I say the world, WHF didn't get the memo, but nevermind)

But this is a classic: page 13 sees a review of a USB cable, that offers "all round improvements over bundled cables"

Could it be magic?

I'm tempted to buy this cable to see if it will make the pictures from my digital camera look better. And if it doesn't, then why not?!!

 

[Andrew Everard]

mrlizard13:So the world has moved on and now accepts
that HDMI cables can't degrade a digital signal

Does it?

mrlizard13:I'm
tempted to buy this cable to see if it will make the pictures from my
digital camera look better.

... words more eloquent in emails, spreadsheets more profitable - we've heard it all before. The test-team are just reporting what they heard, and they're not the only ones with no interest in selling cables who think so...

 

[Anonymous]

Andrew Everard:
mrlizard13:I'mtempted to buy this cable to see if it will make the pictures from mydigital camera look better.

... words more eloquent in emails, spreadsheets more profitable - we've heard it all before. The test-team are just reporting what they heard, and they're not the only ones with no interest in selling cables who think so...

It would be pretty amazing if the same cable didn't improve pictures from a digital camera though wouldn't it, given its science-busting impact on sound.

You can appreciate why so many find it hard to wrap their heads around these biblical miracles - incredibly, no-one at WHF seems to be asking "Why" or "How" something so far fetched can be possible. We are after all talking about packets of data - not analogue.

If you saw moses part the red sea, you'd wonder how he did it.

 

[Ravey Gravey Davy]

mrlizard13:Andrew Everard:

mrlizard13:I'mtempted to buy this cable to see if it will make the pictures from mydigital camera look better.

... words more eloquent in emails, spreadsheets more profitable - we've heard it all before. The test-team are just reporting what they heard, and they're not the only ones with no interest in selling cables who think so...

If you saw moses part the red sea, you'd wonder how he did it.
Apparently it was wind- no shortage of that here.

 

[idc]

Being curious I have wondered and the potential answer is jitter, the timing of the 1s and 0s. What is open to further investigation is how audible and visual jitter is. Some studies say to quite a high degree, others disagree.

 

[AlmaataKZ]

how does a cable affect jitter? can cables affect jitter?

In terms of 'hitting rock bottom' I actually think WHF has improved with the recent makeover. but I also noticed the comment about the USB cable and thought this was a comment that does not add credibility to the mag.

 

[John_S]

Cables don't actively improve sound or picture; we've never said they do. A better quality cable will just degrade the signal less.

You might not notice any difference at all comparing a bundled HDMI cable with a £200 one using a £300 telly. But you would definitely notice a difference on a £2500 TV.

It's like fuel: it's fine to use Tesco petrol in your Nissan Micra. You could use Premium Unleaded, but it won't make much difference. Fill your Ferrari up with the cheapo stuff, though, and it'll fart and bang all the way down the road.

 

[AlmaataKZ]

that is not true for digital signals.

even if you get a degraded signal at the other end, as long as it is still above the error resilience of the system (and withing the spec of the cable), it will be 100% good.

 

[Andrew Everard]

Ah, the old 'digits is digits' argument...

 

[AlmaataKZ]

yes. that is one of the fundamental things with digital - as you know. it does not matter if you see the digit well or vaguely. as long as you can tell the digit, you know what it is. all of it. 100%. and in binary, there are only two.

but that is not the (only) point. I thihk if a hifi mag says a USB cable (or another piece of kit) affects sound (image), it should be prepared to explain (or at least question) the mechanism. if not right in the article (for reasons of space or whatever), then on another suitable occasion, e.g. on the forum or in a special article/blog, especially since challenged.

 

[Andrew Everard]

AlmaataKZ:I thik if a hifi mag says a USB cable (or another piece of kit) affects sound (image), it shoudl be prepared to explain teh mechanism. if not right in the article (for reasons of space or whatever), then on another suitable occasion, e.g. on the forum or in a special article/blog.

As I said before, the test-team is merely reporting what it heard. If any of them wish to add any views on the matter, they know where to find these forums...

 

[chebby]

AlmaataKZ:I thik if a hifi mag says a USB cable (or another piece of kit) affects sound (image), it shoudl be prepared to explain teh mechanism. if not right in the article (for reasons of space or whatever), then on another suitable occasion, e.g. on the forum or in a special article/blog.

I agree.

Surely someone from the specialist audio cable industry (QED?) would welcome the invitation to explain the design principles behind the improved performance from their digital cable products in terms that can be understood by the interested reader.

 

[Clare Newsome]

QED already provide that info for HDMI here on their website (I have linked to this numerous times).

But yes, a USB article could prove stimulating.

 

[John_S]

chebby:
AlmaataKZ:I thik if a hifi mag says a USB cable (or another piece of kit) affects sound (image), it shoudl be prepared to explain teh mechanism. if not right in the article (for reasons of space or whatever), then on another suitable occasion, e.g. on the forum or in a special article/blog.

I agree.

Surely someone from the specialist audio cable industry (QED?) would welcome the invitation to explain the design principles behind the improved performance from their digital cable products in terms that can be understood by the interested reader.

Watch this space. Once we've got the Awards and December issues out (it's all hands to the pumps here at the moment), your questions will be answered.

 

[AlmaataKZ]

hearing is subjective, so reporting what is heard by one or another person inevitably can cross another persons finding, followed by a debate.

that is why I think it is important for a hifi mag to supplement subjective findings with solid factual info - and I found more of it in the made-over mag. It is very welcome, so, as far as I am concerned, the trend is up, not down, as the OP states.

 

[plastic penguin]

mrlizard13:

So the world has moved on and now accepts that HDMI cables can't degrade a digital signal (I say the world, WHF didn't get the memo, but nevermind)

But this is a classic: page 13 sees a review of a USB cable, that offers "all round improvements over bundled cables"

Could it be magic?

I'm tempted to buy this cable to see if it will make the pictures from my digital camera look better. And if it doesn't, then why not?!!

Go on, be a devil - test your own apathy. Most cables have a money-back guarantee from the seller. As Andrew rightly pointed out, the review team test each product and come to firm conclusion, whether good, bad or indifferent. If you question their findings then experience it for yourself and report back.

Has logic really been kicked into the gutter?

 

[AlmaataKZ]

chebby:

AlmaataKZ:I thik if a hifi mag says a USB cable (or another piece of kit) affects sound (image), it shoudl be prepared to explain teh mechanism. if not right in the article (for reasons of space or whatever), then on another suitable occasion, e.g. on the forum or in a special article/blog.

I agree.

Surely someone from the specialist audio cable industry (QED?) would welcome the invitation to explain the design principles behind the improved performance from their digital cable products in terms that can be understood by the interested reader.

yes, would be good to read somethign like that. hopefully, it does not go into marketing mode. e.g. statement like 'xyz coating dramatically reduces distortion' may be technically true, but which distortion? by how much? in what frequency range? does it matter? maybe it already was well below any reasonable level and further reduction makes no difference (except the price, margins adn marketing)?

 

[chebby]

Clare Newsome:QED already provide that info for HDMI here on their website (I have linked to this numerous times).
But yes, a USB article could prove stimulating.

Thanks for the link.

I have read something similar (especially regarding the 'eye pattern' measurements) in an old interview (from 1991) with Julian Vereker regarding the radio-frequency digital signal from a CD laser, and the ways in which it is important to treat the 11mhz signal in terms of it's analogue properties as well as the digital bits contained within.

However, that QED link stops short after describing how a 100 percent competent HDMI cable works. It does not offer any detail about what QED add beyond what a competent, certified HDMI is supposed to do anyway.

 

[Andrew Everard]

Regarding the USB audio cables - and note that description -, the answer, at least from the material published by some manufacturers of these cables, is that they have a) eliminated the power lines from the cables and b) improved the quality/shielding of the data lines.

Now I don't know about you (of course I don't), but I can see how not having power buzzing away next to the data lines could reduce the chance of any interference, and thus give the error correction in the receiving device less work to do.

And in my (purely subjective) experience, the less work the DAC needs to do reconstructing the digital signal, the better it tends to sound.

Of course the removal of the power lines does arguably mean that these cables are no longer strictly to the USB standard; rather they're digital audio cables that just happen to have USB plugs at either end, in order to suit the equipment with which they're designed to be used.

 

[AlmaataKZ]

Clare Newsome:

QED already provide that info for HDMI here on their website (I have linked to this numerous times).

But yes, a USB article could prove stimulating.

I have read the QED article. while it contains no incorrect statemetns, it does not actually say that hdmi (or any digital cable) affect sound/video quality. for example:

---------- As we speed up the skipping movement, the opening will begin to close, eventually coming to a point where it is no longer big enough to jump through. HDMI cables need this 'eye' to be open, so that it is easy to determine the difference between when the rope is 'up' and when it is 'down'. Increasing the speed of the digits and/or increasing the length of the cable, also reduces the size of the 'eye'. Measuring poorer quality cables already reveals they produce a smaller 'eye'. So, as the digit rate increases, the 'eye' of poorer cables gets smaller to the point where 'up' and 'down' are indistinguishable and the receiving equipment cannot understand the information (the digits) that are being sent. --------

does nto matter if the eye is small or big. the eye jsut need to be big enough - within the spec.

-----------------Real world variation and tolerances may mean that a cable produced to simply 'meet' the specification on paper, may not actually comply every time in production. Similarly, both electronic display and source equipment will experience some variation in production and may also suffer some degradation of their performances over time. This means it's not enough for a cable to merely meet the required specifications, it always needs to exceed them.

that is not a design issue. that is a quality assurance/quality control issue. there is no need to exceed the spec. a spec compliant cable of good workmaship will work all the time in the conditions it is designed to work in ovetr its design life.

Unfortunately, these are not the only factors that contribute to poor performance. Poor choice of materials, imprecise control of cable geometries during manufacture, as well as physical imperfections and construction tolerances are all sources of error which can degrade performance, even after the original design has been passed as adequate. ----------

that is not a design issue. that is a quality assurance/quality control issue. there is no need to exceed the spec. a spec compliant cable of good workmaship will work all the time in the conditions it is designed to work in over its design life.

------To use an analogy, if someone fires a gun at you, there are some who would argue that being missed by just one inch is exactly the same as being missed by a mile. However, when the gun is being fired as often as it is in an HDMI cable, and in addition, being fired from a hand that is shaking (however minutely) I personally would feel a lot happier if I was confident the bullet would miss by a mile!------

the analogy is good for explaining, but it is taken out of factual context. proper spec and desing would mean that the cable operates in the 'mile' zone, and not in the 'one inch' zone

-----What about the HDMI system's own ability to correct errors? QED's response to that question is simply: "Why introduce errors in the first place? Isn't it better to accurately receive every last detail of the uncompressed image, exactly as it was transmitted, instead of what the error correction thinks it should have been?"-------

again, having cable errors may or may not matter. if the system operates well above error-correction threashholds, it may not mattter at all. so this arguemtn needs to be quantitative to demonstrate anyhting.

so, the article does not say hdmi affects sound/image. it says that a cable has to be made well and implies that some headroom is desirable, without saying how much. marketing.

 

[Andrew Everard]

AlmaataKZ:so, I can conclude that any well designed and made hdmi cable providing the eye within spec is as good as it gets.

Good - be happy with all that money your certainty has saved you. No one is holding a gun, whether in a shaky or steady hand, to your head, and forcing you to buy something which you are confident will make no difference whatsoever.

And, moving on...

 

[AlmaataKZ]

ok, moving on.

p.s. i edited my post before I read yours

 

[Zarn_Smith]

Actually when I first heard about "super duper" USB cables I also first thought "What utter tosh!", but after some research I am now of the belief that there are senarios where a higher quality cable may make a difference.

It is all to do with design choice. With HDMI there is no protocol performing error checking that the data sent down the cable is what is recieved. (The design choice here is that cost would be prohibative to implement because of the bandwidth being thrown down the cable).

So you ask how does this affect USB. Well it seems there are a number of different ways data can be sent down a USB cable. We are all used to how computers use USB. Essentially packets are guaranteed delivery. Well it is also possible to send data down USB where the packets are not guaranteed. This method would be used for data that is time sensitive (such as VoIP). I guess if that protocol was implemented for HiFi purposes then a better cable might mean a better signal.

Link for those that want to perform further self study: http://www.beyondlogic.org/usbnutshell/usb4.shtml

 

[bigboss]

John_S:

You might not notice any difference at all comparing a bundled HDMI cable with a £200 one using a £300 telly. But you would definitely notice a difference on a £2500 TV.

Sorry, but I couldn't notice any difference between different HDMI cables on my 50-inch Kuro. TVs can't get better than that, can they?

 

[Anonymous]

Andrew Everard:Ah, the old 'digits is digits' argument...

Yup, you know, the one that is based on sound fact.

I'd have no issue with the mag saying that a USB cable can make a difference to sound, if only they were able to provide some sort of insight as to how on earth that's possible.

One of your guys on this thread (John_S) has suggested that a better quality cable degrades signal less. He's right! With analogue. Not so with digital. It's a bit worrying that the assistant production editor made a boob like that.

We are talking packets of data. 1's and 0's. They are either there, or they are not. A '1' doesn't become a '0.5' because it got degraded along the way.

Just saying it's what the test team heard isn't good enough for a mag of your standing. You should aim for better than that, your readers deserve it.

So until WHF comes up with some sort of explanation for this miracle, there's plenty of us that will continue to have a fairly suspect view of your test team. If I was in that test team and I heard a difference with a USB cable, I'd be blown away as to how and why that's even possible.

To boldly claim something that, scientifically, is revolutionary without having an inch of curiosity as to how...? Just doesn't cut it.

I look forward with anticipation to the future issue as promised by John_S where this miracle is explained.