Kogan challenges Currys & John Lewis regarding HDMI cables

[bigboss]

Any HDMI cable that is on sale here today has to conform to industry standards, from the £2 ones up to the £300 ones, they all have to be able to do what they were designed to do, so if the £2 cables measure up to industry standards, and the £300 ones do too, what differences could there possibly be between them?

That'll be the features then.

I'm not suggesting that the wildly different prices can always be justified, but you asked what could be different about 2 cables that match the same specification...

There's also the point that only a cable constructed to the highest quality will work beyond a certain length, cheaper cables are fine up to about 5m but beyond that will start to fail due to signal attenuation. A higher quality cable will be good for up to 15m and yet both would pass the testing criteria (otherwise they wouldn't be on sale). And of course the tests themselves will categorise the cable into one of two types, standard or high-speed. So they're most definitely not all the same.

Passing or failing the testing criteria over any length doesn't necessarily correlate with cost of the cable. Some expensive cables have failed the test, & some cheap cables have passed it.

There are some very well constructed cheap cables, like ThatCable.

 

[Lee H]

I also have a variety of colours of cables. See, there are differences everywhere

 

[Lee H]

In fairness, the section you quoted does appear only to relate to components and not cable, as tremon suggested. The only distinction referred to with cables is whether it's high speed.

It's possible I may have mis-read :wall:

 

[Anonymous]

Thanks. You're quoting from the answer to the question "Q. What are the HDMI-related questions consumers should ask when shopping for a new CE or PC device?"

Since I am not interested in the entire HDMI spec, I'll leave it at this: I don't think that a cable qualifies as Consumer Equipment. But I see your CE assertion, and I'll raise you a cable FAQ:

"High Speed (or “category 2”) HDMI cables [..] can successfully handle 1080p signals including those at increased color depths and/or increased refresh rates"

I also note that the High Speed qualification says nothing about 4k, so I was wrong about that. In the interest of this discussion, I'll also post this snippet (same link, 10 lines above):

"All HDMI products are required to be certified by the manufacturer as part of the HDMI Compliance Test Specification. However, there may be instances where cables bearing the HDMI logo are available but have not been properly tested. HDMI Licensing, LLC actively investigates these instances to ensure that the HDMI trademark is properly used in the market. We recommend that consumers buy their cables from a reputable source and a company that is trusted."

So it seems that, if you encounter differences between cables, the correct course of action would be to report both the manufacturer and your supplier to the HDMI for trademark violation.

 

[Anonymous]

It's possible I may have mis-read :wall:

no worries. You still provided an interesting link

 

[The_Lhc]

I also note that the High Speed qualification says nothing about 4k, so I was wrong about that.

Not necessarily:
Version 1.4
HDMI 1.4 was released on May 28, 2009, and the first HDMI 1.4 products were available in the second half of 2009.[55][111] HDMI 1.4 increases the maximum resolution to 4K × 2K, i.e. 3840 × 2160p at 24 Hz/25 Hz/30 Hz or 4096 × 2160p at 24 Hz (which is a resolution used with digital theaters)

Yes, it's wikipedia but there's no reason to doubt it, the references are excellent for this article.

 

[Anonymous]

Isn't this discussion drifting into irrelevant technicalities? It's clear that there are different specifications of cables, what is not clear is how so many cables that were endorsed by the powers that be have been found to be substandard against similarly specced cables by What Hifi.

Those cables were either wrongly endorsed or their reviews are flawed. It's one or the other.

 

[Anonymous]

diversityfg

Your logic seems quite perverse to me. Isn't that like saying all cars that pass an MOT should all have to have the same fuel consumption and accelerate the same speed ?

That has to be the barmiest analogy this side of the Goon brothers.

The specifications for all cars are different. MOT testing is simply supposed to make sure older cars are still road worthy and safe, nothing more.

The specs for HDMI cables are relatively simple. At the basic level they supply a picture and an audio signal.

If there are problems with the picture, it shows up as banding, or worse. If there are problems with the digital audio signal, it shows up as drop outs.

There are certainly no "deeper blacks" or "defined bass"...that much is certain. If a cable works, and has all the features you need, then the cheapest is the one to get...unless you like the colour of the various "so called" high end cables. Same goes for toslink, only even simpler.

 

[Petherick]

Gold plating is used mainly because it is the only metal that doesn't rust or oxidise (turn green) when exposed to air/humidity over long periods of time.

You missed the irony of my post, obviously.

And you're wrong, most metals don't turn green when they oxidise. And gold only has the lowest tendency (i.e. not NO tendency) to oxidise in air.

 

[Anonymous]

I read the odd what hifi review to see if anything has changed in the way your review products now and again but generaly i dont. Test equipment such as distortion analysers are typically used to measure the perfomance of the aplifiers and playback equipment such as CD players, not the music itself.

 

[The_Lhc]

Test equipment such as distortion analysers are typically used to measure the perfomance of the aplifiers and playback equipment such as CD players, not the music itself.

I can't work out if you think that's a good thing or not? Personally speaking it's the music that's important and a distortion analyser can't tell me what a piece of equipment actually sounds like, which is why I don't bother reading those magazines that include all that (if there are any left).

 

[Clare Newsome]

Just wondered if anyone had read the link I posted to:

Some interesting lab results mentioned in this article

It details some analysis into two (certified) cables to reveal why they may be performing differently. Very interesting.

Here's how it kicks off, to whet your appetite:

"When it comes to HDMI performance, let me restate that reliability has been the major issue, and it usually surfaces with people breaking the rules.

This is not new, we’ve been following specification rules since the invention of the wheel, so why has it now taken such a toll?

In our experience, some manufacturers have shown a lack of competency in making HDMI products right the first time and continuing that over the products’ life span. It is absolutely false that all cables are the same, even at short lengths."

Rest of article, including lab analysis here.

 

[bigboss]

Just wondered if anyone had read the link I posted to:

Some interesting lab results mentioned in this article

It details some analysis into two (certified) cables to reveal why they may be performing differently. Very interesting.

Here's how it kicks off, to whet your appetite:

"When it comes to HDMI performance, let me restate that reliability has been the major issue, and it usually surfaces with people breaking the rules.

This is not new, we’ve been following specification rules since the invention of the wheel, so why has it now taken such a toll?

In our experience, some manufacturers have shown a lack of competency in making HDMI products right the first time and continuing that over the products’ life span. It is absolutely false that all cables are the same, even at short lengths."

Rest of article, including lab analysis here.

I read the article. What I can infer from that is, that a cable may pass or fail according to how it's constructed. I haven't found anything pertaining to audio & visual differences when 2 cables work, unless I've missed something.

EDIT: Both your links direct towards the same page.

 

[Clare Newsome]

I think you're missing the point - this was cables apparently submitted by a professional installer for testing to these labs. Products that were commercially available on the market (ie HDMI specified) that behaved very differently and were built very differently.

I thought it would be of interest to the people suggesting that all cables - if carrying the HDMI logo - were essentially the same. This article would suggest not.

It also contests the assumption, made by some, that 'HDMI cables either work or they don't' - that can vary on the system they're being used in.

 

[Anonymous]

I think you're missing the point - this was cables apparently submitted by a professional installer for testing to these labs. Products that were commercially available on the market (ie HDMI specified) that behaved very differently and were built very differently.

I thought it would be of interest to the people suggesting that all cables - if carrying the HDMI logo - were essentially the same. This article would suggest not.

It also contests the assumption, made by some, that 'HDMI cables either work or they don't' - that can vary on the system they're being used in.

This would appear to suggest that one of them did not work.

However, the one that failed used a very thin solid gauge wire size for the HDCP/EDID channel compared with the cable that worked. The HDCP/EDID wires within the cable that failed are at least two times smaller in diameter than the one that worked

 

[noogle]

Clare -

As a respected, unbiased expert, can you take the Kogan Challenge for us? Would be interesting to see if you could spot cable differences say more than five out of ten times.

 

[Clare Newsome]

I think you're missing the point - this was cables apparently submitted by a professional installer for testing to these labs. Products that were commercially available on the market (ie HDMI specified) that behaved very differently and were built very differently.

I thought it would be of interest to the people suggesting that all cables - if carrying the HDMI logo - were essentially the same. This article would suggest not.

It also contests the assumption, made by some, that 'HDMI cables either work or they don't' - that can vary on the system they're being used in.

This would appear to suggest that one of them did not work.

However, the one that failed used a very thin solid gauge wire size for the HDCP/EDID channel compared with the cable that worked. The HDCP/EDID wires within the cable that failed are at least two times smaller in diameter than the one that worked

Read it again - the one that 'failed' only did so in a certain system; it worked fine in another:

"When tested with one TV, however, only one of the cables worked, but with another TV they both worked."

 

[Alec]

Horizon will tonight examine the idea that colour perception is dependant on age, mood etc. And we often have different perceptions and/or tolerances for colours, light, sound if ill.

Subjective reviews then - totally useless unless we can remove all those variables.

 

[Clare Newsome]

Clare -

As a respected, unbiased expert, can you take the Kogan Challenge for us? Would be interesting to see if you could spot cable differences say more than five out of ten times.

Our test team are certainly looking forward to getting the Kogan in for review. Nothing would delight us more than if a £4 cable is excellent - we've already given a full five stars to this £5 cable, and it 'd be great to find another bargain.

 

[bigboss]

Clare -

As a respected, unbiased expert, can you take the Kogan Challenge for us? Would be interesting to see if you could spot cable differences say more than five out of ten times.

The only way it'll work is by inviting an audience of, say, 20 & find out the percentage of people able to correctly identify the cables.

 

[Andrew Everard]

The only way it'll work is by inviting an audience of, say, 20 & find out the percentage of people able to correctly identify the cables.

Nah, statistically insignificant – you need at least 200, or even better 2000.

 

[Clare Newsome]

Horizon will tonight examine the idea that colour perception is dependant on age, mood etc. And we often have different perceptions and/or tolerances for colours, light, sound if ill.

Which is why we (a) team test - so it's never just one person's percpetions being reported and (b) urge everyone to try before they buy, regardless of product price or type.

 

[Andrew Everard]

Horizon will tonight examine the idea that colour perception is dependant on age, mood etc. And we often have different perceptions and/or tolerances for colours, light, sound if ill.

Subjective reviews then - totally useless unless we can remove all those variables.

Why Planes Crash is on NatGeo tonight – doesn't mean Heathrow will be deserted in the morning.

 

[Anonymous]

Read it again - the one that 'failed' only did so in a certain system; it worked fine in another:

"When tested with one TV, however, only one of the cables worked, but with another TV they both worked."

I still parse the above as "some cables work, and some don't". That it also depends on the connecting equipment isn't really at all surprising. Maybe this is just a case of babylonia, but the quote above does not read to me as "one of the cables produced an image quality visibly inferior to the other".

 

[Anonymous]

I think you're missing the point - this was cables apparently submitted by a professional installer for testing to these labs. Products that were commercially available on the market (ie HDMI specified) that behaved very differently and were built very differently.

I thought it would be of interest to the people suggesting that all cables - if carrying the HDMI logo - were essentially the same. This article would suggest not.

It also contests the assumption, made by some, that 'HDMI cables either work or they don't' - that can vary on the system they're being used in.

This would appear to suggest that one of them did not work.

However, the one that failed used a very thin solid gauge wire size for the HDCP/EDID channel compared with the cable that worked. The HDCP/EDID wires within the cable that failed are at least two times smaller in diameter than the one that worked

Read it again - the one that 'failed' only did so in a certain system; it worked fine in another:

"When tested with one TV, however, only one of the cables worked, but with another TV they both worked."

Fair enough. Still, a rare example i should imagine. I am still concerned that any cables reviewed that got less than top marks must have been wrongly endorsed, presuming What Hifis assessment of them was correct.

This casts doubt over those that endorse these cables as 100% capable.