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Tomm
11-05-2009, 07:12 AM
Hey,

Anyone know where I can get around 15m of cheap HDMI cable (Not of this £200 gold plated, shielded from nuclear radiation and EMP crap)?

Thanks,

Tom

J0SH
11-05-2009, 09:12 AM
http://www.amazon.com/GOLD-PREMIUM-HDMI-CABLE-HDTV/dp/B000QKKAPE/ref=sr_1_1?ie=UTF8&s=electronics&qid=1242033051&sr=8-1

Is that what you're looking for? 50FT apparently.

N!ck
11-05-2009, 12:38 PM
I can't garuntee how it will look. HDMI has serious signal degradtion on long lengths (and as it's a digital signal, once it's gone you can't amplify it back). From 3 of the reviews on Amazon though that doesn't seem the case. In theory it should be just like that one bad review says. They may have improved HDMI technology since it was created (as it was a rushed interface) so I don't know. Theoretically you would be much better off runnng a component cable at this length.

The really expensive cables use higher quality components than usual or repeaters to try and get around this.

An article on the subject of long HDMIs. http://www.bluejeanscable.co.uk/articles/how-long-can-hdmi-run.htm

Mentor
13-05-2009, 12:17 AM
15m is quite a way for an HDMI cable so your unlikey to find any dirt cheap ones that can make the range "/
Ebuyer has one for £27 http://www.ebuyer.com/product/147179 though which probabaly isnt to bad concidering the distance.

Tomm
13-05-2009, 07:20 AM
Well, I did not mean dirt cheap as such. Just not something silly like £150 for a cable :P However, in hindsight I most likely do not need a cable that long. Ill get some string out and measure the exact distance that ill need later on today.


15m is quite a way for an HDMI cable so your unlikey to find any dirt cheap ones that can make the range "/
Ebuyer has one for £27 http://www.ebuyer.com/product/147179 though which probabaly isnt to bad concidering the distance.

tm
13-05-2009, 09:17 AM
The gadget show did a test of HDMI cables on the programme and found no difference what-so-ever between a cheapo tesco effort and a £150 gold plated supermega thing.

That 15m ebuyer one posted above is pretty good for the price I must say. I'd probably settle for that one if I were you and definitely need the length.

Many good priced products: http://www.ebuyer.com/search?store=4&cat=24&subcat=1491

N!ck
13-05-2009, 03:24 PM
The gadget show did a test of HDMI cables on the programme and found no difference what-so-ever between a cheapo tesco effort and a £150 gold plated supermega thing.

That 15m ebuyer one posted above is pretty good for the price I must say. I'd probably settle for that one if I were you and definitely need the length.

Many good priced products: http://www.ebuyer.com/search?store=4&cat=24&subcat=1491

No, it wasn't a cheap Tesco one vs a £150 one. It was a £20 Logitech one vs at £70ish one, both short/standard length. For short lengths the cheaper options are fine. If I was connecting two expensive devices such as a Blu-ray player and decent TV then i'd spend the cash on the Logitech one rather than a cheap £3 one as it's worth it. When you start talking about long distances it makes a big difference.

Kyle!
13-05-2009, 03:59 PM
HDMI sends DIGITAL signal, so for instance, monster cable selling their £200 cables will have no difference than the £20 ones, you can't send a 1 or a 0 where it receives a better 1 or a 0, it either gets there or it doesn't. Engadget have been posting loads of articles on how Monster cable have been ripping off customers.

You can get cheap ones from comet, disguised as PS3 only HDMI cable's that are only £15.

N!ck
13-05-2009, 04:02 PM
HDMI sends DIGITAL signal, so for instance, monster cable selling their £200 cables will have no difference than the £20 ones, you can't send a 1 or a 0 where it receives a better 1 or a 0, it either gets there or it doesn't. Engadget have been posting loads of articles on how Monster cable have been ripping off customers.

You can get cheap ones from comet, disguised as PS3 only HDMI cable's that are only £15.

Yes exactly, over a short distance there's not difference in the quality produced by a £15-20 branded one compared to an over £100 one.

Mentor
13-05-2009, 08:52 PM
Yes exactly, over a short distance there's not difference in the quality produced by a £15-20 branded one compared to an over £100 one.
There's actually no difference between a £3.59 and a £100 one ether, over any length. To think there would be, or even could be, requires a fundamental misunderstanding of how the technology works.

N!ck
13-05-2009, 09:03 PM
There's actually no difference between a £3.59 and a £100 one ether, over any length. To think there would be, or even could be, requires a fundamental misunderstanding of how the technology works.

A digital signal cannot go forever without being boosted. HDMI was a rushed technology and is only efficient over short lengths. Once a bit of a digital signal has been lost no amount of amplifying is going to bring it back. All cables have resistance and attenuation and the longer the cable the more resistance there is to lose some of the bits of data. HDMI 1.3 is a lot better, but still susceptible. Have a read here? http://www.bluejeanscable.co.uk/articles/how-long-can-hdmi-run.htm

Mentor
13-05-2009, 10:42 PM
A digital signal cannot go forever without being boosted. HDMI was a rushed technology and is only efficient over short lengths. Once a bit of a digital signal has been lost no amount of amplifying is going to bring it back. All cables have resistance and attenuation and the longer the cable the more resistance there is to lose some of the bits of data. HDMI 1.3 is a lot better, but still susceptible. Have a read here? http://www.bluejeanscable.co.uk/articles/how-long-can-hdmi-run.htm
All true, but entirely missing the point, unless your under the impression company's make and sell ranges of items that simply do not work?

If a company sells a 15m hdmi cable, that cable will work when connected. If it doesn't it'll be sent back to be replaced with one that does. If none of a company's cable's work, having to replace a cable an infinite amount of times is a pretty sure way to go out of business.
So we have a dirty cheap 15m cable, that works. Now you could go an spend more money and get an expensive hdmi cable that also works, but the question you have to ask is why? Its not like a working cable can work more, or work better, any more than I can turn my computer oner once its on...

N!ck
13-05-2009, 10:54 PM
All true, but entirely missing the point, unless your under the impression company's make and sell ranges of items that simply do not work?

If a company sells a 15m hdmi cable, that cable will work when connected. If it doesn't it'll be sent back to be replaced with one that does. If none of a company's cable's work, having to replace a cable an infinite amount of times is a pretty sure way to go out of business.
So we have a dirty cheap 15m cable, that works. Now you could go an spend more money and get an expensive hdmi cable that also works, but the question you have to ask is why? Its not like a working cable can work more, or work better, any more than I can turn my computer oner once its on...

Well, I don't know whether you ever experienced it with analogue signals, for instance scart cables. For me there was a large noticeable difference in the image from my video recorder from going from the cheap, nasty scart cable that came with it to an in-expensive £5 gold-plated one. The difference really was noticeable. The same with my PS1/PS2. Rather than using the AV to scart adapter that came with it I bought an in-expensive Playstation scart cable and the difference was definately worth it.

the difference is not so much with HDMI as it's all digital, but basically the set standard is something like 90% (I've not researched this figure, it's off the top of my head), which means that as long as 90% or more of the original digital signal reaches the device at the other end then it's good to go. With a longer cable of still low quality you're going to be pushing this limit to the edge (and maybe some of the really cheap companys are just ignoring the set standards?), so you'd want a decent cable to keep the image still good.

An interesting qoute from Wikipedia about HDMI cable length here.


The HDMI specification does not define a maximum cable length, but because of signal attenuation there is an upper limit to how long HDMI cables can be made.[56] The length of an HDMI cable depends on the construction quality and the materials used in the cable.[56] Adaptive equalization can be used to compensate for the signal attenuation and intersymbol interference caused by long cables.

To reduce the confusion about which cables support which video formats, HDMI 1.3 defines two categories of cables: Category 1 certified cables, which have been tested at 74.5 MHz (1080i/720p), and Category 2 certified cables, which have been tested at 340 MHz (1600p).[57] Category 1 HDMI cables are to be marketed as "Standard" HDMI cables, and Category 2 HDMI cables are to be marketed as "High-Speed" HDMI cables.[1] This labeling guideline for HDMI cables went into effect on October 17, 2008.[58][59] Category 1 and 2 cables can either meet the required parameter specifications for inter-pair skew, far-end crosstalk, attenuation, and differential impedance or they can meet the required non-equalized/equalized eye diagram requirements.[57] A cable of about 5 meters (16 ft) can be manufactured to Category 1 specifications easily and inexpensively by using 28 AWG (0.081 mm²) conductors.[56] With better quality construction and materials, including 24 AWG (0.205 mm²) conductors, an HDMI cable can reach lengths of up to 15 meters (49 ft).[56] The HDMI website has stated that many HDMI cables under 5 meters of length that were made before the HDMI 1.3 specification can work as a Category 2 cable but cautions that only Category 2 tested cables are guaranteed to work.[60] Long cable lengths can cause instability of HDCP and blinking on the screen due to the weakened DDC signal which HDCP requires. HDCP DDC signals must be multiplexed with TMDS video signals to be compliant with HDCP requirements for HDMI extenders based on a single Category 5/Category 6 cable.[61][62] Several companies offer amplifiers, equalizers, and repeaters that can string several standard HDMI cables together. Active HDMI cables use electronics within the cable to boost the signal and allow for HDMI cables of up to 30 meters (98 ft).[63] HDMI extenders that are based on dual Category 5/Category 6 cable can extend HDMI to 250meters while HDMI extenders based on optical fiber can extend HDMI to 100+ meters (328 ft).[56][63] This is due to be extended again in 2009, as companies such as Lindy Electronics release units capable of distances over 300 metres (980 ft) on a single optical fiber cable.

Mentor
13-05-2009, 11:10 PM
Well, I don't know whether you ever experienced it with analogue signals, for instance scart cables. For me there was a large noticeable difference in the image from my video recorder from going from the cheap, nasty scart cable that came with it to an in-expensive £5 gold-plated one. The difference really was noticeable. The same with my PS1/PS2. Rather than using the AV to scart adapter that came with it I bought an in-expensive Playstation scart cable and the difference was definately worth it.

the difference is not so much with HDMI as it's all digital, but basically the set standard is something like 90% (I've not researched this figure, it's off the top of my head), which means that as long as 90% or more of the original digital signal reaches the device at the other end then it's good to go. With a longer cable of still low quality you're going to be pushing this limit to the edge (and maybe some of the really cheap companys are just ignoring the set standards?), so you'd want a decent cable to keep the image still good.
Indeed like most people i have witnessed how crappy an analogue signal can get when passed through cheap wiring. The thing to note here is that is that HDMI is NOT an analogue signal. Its a digital one, so signal degradation physically cannot happen in the same way it does with an analogue signal. Theres no variation, you ether get a picture or you dont, theres no imbetween, theres ether enough data or not enough. Digital unlike analogue is all or nothing.
Hence why alot of people are angry at manufactures for tricking people in to buying hugely expensive hdmi cables with impressive sounding parts simply because they are used so to how analogue cabling works.

And here, the point i made above comes in to play, Since there selling a cable, that means the cable is able to transfer enough data in order to work, meaning you'll get exactly the same picture with a cheap as chips hdmi cable as you would if you wanted to use a jewel encrusted, solid gold super hdmi cable that cost you four grand.

Aside from that, the gold plating part is purely there to sound good, the connector your plugging your cable in to isnt gold plated anyway, so any advantage this could have theoretically provided is out of the window before you even get started.

N!ck
13-05-2009, 11:19 PM
Indeed like most people i have witnessed how crappy an analogue signal can get when passed through cheap wiring. The thing to note here is that is that HDMI is NOT an analogue signal. Its a digital one, so signal degradation physically cannot happen in the same way it does with an analogue signal. Theres no variation, you ether get a picture or you dont, theres no imbetween, theres ether enough data or not enough. Digital unlike analogue is all or nothing.
Hence why alot of people are angry at manufactures for tricking people in to buying hugely expensive hdmi cables with impressive sounding parts simply because they are used so to how analogue cabling works.

And here, the point i made above comes in to play, Since there selling a cable, that means the cable is able to transfer enough data in order to work, meaning you'll get exactly the same picture with a cheap as chips hdmi cable as you would if you wanted to use a jewel encrusted, solid gold super hdmi cable that cost you four grand.

Aside from that, the gold plating part is purely there to sound good, the connector your plugging your cable in to isnt gold plated anyway, so any advantage this could have theoretically provided is out of the window before you even get started.

There is a percentage of the signal lost, and like you said, that lost signal is digital, so is completely gone. While that difference is small enough for it to be compliant it is still there.

Get me a £3 HDMI cable and a £20 one of the same length. There will be a noticeable difference I guarantee you. Compare that same £20 one to a £100 one. There will be no noticeable difference. It's getting late. I'm off to bed. Night.

Kyle!
13-05-2009, 11:21 PM
There is a percentage of the signal lost, and like you said, that lost signal is digital, so is completely gone. While that difference is small enough for it to be compliant it is still there.

Get me a £3 HDMI cable and a £20 one of the same length. There will be a noticeable difference I guarantee you. Compare that same £20 one to a £100 one. There will be no noticeable difference. It's getting late. I'm off to bed. Night.

There won't be a difference, if there is a difference the £3 one is broken and needs to sent back.

Metric1
14-05-2009, 02:28 AM
I have Monster HDMI cables, they're mint! But not worth the price..

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