The team discover the truth behind HDMI cable quality claims. Also, Kate Bush - her concert is a sell-out, but if you got a second-hand ticket will you be able to get in? Plus the latest criminal scam that's outwitting even the country's brightest minds.

if you can stand it, it might be interesting. might not be too i guess.

Is that the 'truth' that a digital signal gets through or not?

that's the one.

i'm a scientist. i subscribe to this model. i understand that saying an expensive HDMI lead gives a better picture is like saying an expensive USB lead will give me better print quality.

that was until i saw what happened when my mate hooked up his three grand 50 inch panasonic to his onkyo receiver with a few hdmi leads and blind test you could tell the difference. presumably it was some rf interference picked up in the lead making it to the screen.

It's Watchdog - so no doubt we will get a dumbed down report that misses the point entirely.

Not all HDMI cables are created equally. There are different standards and older cables may not carry some of the modern functions (as I found out to my frustration recently with an HDMI cable stripping out Dolby Digital information.

Isn't it true that older HDMI leads can't cope with 3D?

There are different versions of HDMI

http://en.wikipedia.org/wiki/HDMI#Version_1.0_to_1.2

I think you need 1.4 for 3D.

People think that HDMI is digital, but the signals going down an HDMI cable are always analogue at their heart.

They are just interpreted as "digital" at the receiving end. They are merely voltages in reality.


"Digital" is really an encoding method, using analogue signals as the carrier.

Analogue signals will degrade, but the piggy-backed "digital signal" is very resilient to this.

No it isn't.

You don't. I use a 99p shop one for 3D.

I'd love to know how it managed that feat. That would take some fairly sophisticated processing of the data stream that I doubt a mere cable is capable of. Given that the audio data is embedded in the video data.

The cable spec is separate from the HDMI 1.x spec. See here

http://www.hdmi.org/consumer/finding_right_cable.aspx

You basically need a High Speed cable for 3D.

The HDMI 1.x spec is for the hardware at each end of the cable more than the cable itself.

The pound shop ones are 1.4 anyway, so your 99p one may also be.
http://www.poundland.co.uk/signalex-hdmi-cable-1m

Well they did the 'A cheap one is as good as an expensive one' thing.

Perhaps it only really makes a difference with more high end equipment?

I'm sure a humax HDR and 40in LED TV don't really need an expensive HDMI.

I've yet to see an HDMI cable that doesn't work perfectly with 3D (even the VERY, VERY early ones), mind you with how 3D has flopped (yet again ) it's doesn't really matter.

They done this on the gadget show which is made with Currys and I think they gave the correct info?

My dads just bought a 3D TV from currys. I think he was a bit embarrassed as I had to stand arguing with the sales person of why we didn't need a £40 HDMI cable (started of at £70) to be able to view 3D. He was adamant that the cables I had wouldn't work and wouldn't believe me when I said that if they didn't then I could spend £5 or less on new ones. And yes the cables we already had, worked. Some of them must be 6 years old.

It doesn't make any difference to picture and sound quality.

As long as the cable is of decent construction and properly shielded there will be zero difference. Anyone in a shop, or in the retail industry who tells you any different is lying plain and simple.

A £5 cable from Amazon will perform as well as some of the cables with more MONSTERous prices.

Where paying a bit more may be of benefit is with longer cable runs, and "maybe" in set ups where there may be more interference than in normal domestic setups IF the more expensive cable has better shielding than the cable that is having problems.

Poundland cables work fine for 3D.

I suspect it had something to do with the age of the cable. An HDMI 1.0 that i had spare would not allow the Audio Return Chanel to work correctly (it passed PCM stereo, but as soon as the source was switched to Dolby Digital everything went silent.)

It was suggested I should change the cable, so I went for an Amazon basics (still only £3.99) but 1.4 spec plus "ARC compatibility" and ethernet connection and it all worked fine. ( I should mention I was using the ARC channel)

My point being not the cost, but the construction of the changing format of HDMI specification that can lead to functions not working. (lip sync, for example, between 1.2 and 1.3 (if memory serves.

Still - could be worse - we could be stuck with the SCART

ARC uses an extra pin not used by the older spec. From the HDMI wiki

ARC and HEC[edit]

HDMI 1.4 introduces two features called ARC (Audio Return Channel) and HEC (HDMI Ethernet Channel).[59][60][95] These features use two pins from the connector: a previously unused pin and the hot plug detect pin.[95]

What isn't clear if this pin was actually wired on old cables.

This is nothing to do with the cost of a hdmi cable. If the cable is specified as being 1.4 capable (high speed) it should work the same whether it cost 99p or £99.00

If ARC was working on PCM stereo then it should have worked for Dolby Digital. Unless of course the cable was not constructed to ARC spec. ARC uses two connections that were unspecified in the original cable spec. So possible they were not wired properly in a cable not specifically designed to the ARC spec.

Even so it's a bit odd it would pass one format of audio but not another, it is after all just a stream of ones and zeros, the cable has no idea what those ones and zeros mean. I can only think it was some bandwidth issue that allowed PCM stereo to get through well enough to be decoded but Dolby Digital was corrupted enough for the amp to discard it and mute. Though DD in it's compressed format is lower bandwidth than PCM Stereo (at CD equivalent spec) so perhaps it was being decoded at source and sent as six full bandwidth streams?

And I am certain SCART was some French joke invented to annoy the hell out of everyone

Or you could have had a huge handful of phono plugs like the USA, instead of one single plug

And the phono's didn't even do RGB!

At least phono plugs tend to stay in the socket. Unlike SCART which falls out as soon as you turn your back on the damn thing.

And I agree with you Chris. I was merely pointing out that (regardless of cost) not all HDMI cables are the same and pondered whether Watchdog would go that in depth.

They didn't

I suspect we are singing from the same hymn sheet

Latterly they did do component - but at an increase in the phono count.