Maestro HDMI Cables - Anyone used them?

HDMI signals tend to prefer to travel in a straight line

Joe , the rest of the post about mechanical strength and fire regulations , absolutely fine , but as an Electronics engineer I have to say that the above statement is just ..... what can I say ! Im dumbfounded , it has no merit .... there Ive been nice once today at least !

Avoiding 90 degree bends in cable is common sense , but for mechanical reasons due to stress on the cable only , the electrical signal couldn't care less ! It doesnt carry enough current to be of any electrical significance.
 
Hello andy1249

The problem for a lot of wall mounted Displays and folk running cables around a room perimeter is that many folk do have to go through a tight Radius as they enter/exit the Display or hit a corner and as you say this can cause physical disconnects and other mechanical problems.

When folk associated with the design of the HDMI Standard also talk about data problems due to tight bends (even where there is no physical problem) I'll listen to their advice on how best to install cables - 'If the display or
the source has limited room behind for the connector to form a decent radius, a cable will have a very
hard time staying connected. Conversely, you don’t want to have tight 90º kinks in the cable, otherwise
you may start to degrade data from the severity of the bend'.

(Jeff Boccaccio writing for CEPro).

Joe
 
The long cables that work in all setups tend to include a degree of over engineering and ensure the individual signal lines are well screened and stay put when a cable does have to negotiate a bend.
Thanks... this is exactly what I was getting at although I can see that perhaps my original post was not clear in this respect, hence the additional (interesting) debate! I don't actually have a very long cable run (2m) but it will have a tight bend in one spot, which is what I need the cable to physically cope with.
 
HDMI.org have two cable rating cat 1 (standard speed) and cat 2 (high speed)

So that means I'm watching everything in slow motion as my cable is worth a few quid :rolleyes:





:D

I'm with the engineers on this one, we always know our subject back to front, and don't believe pap typed and quoted off the internet super-holy-grail-highway.
 
If the display or
the source has limited room behind for the connector to form a decent radius, a cable will have a very
hard time staying connected. Conversely, you don't want to have tight 90º kinks in the cable, otherwise
you may start to degrade data from the severity of the bend'
It would be very easy to just ridicule the part in bold , I wont though , and try to get you to just think about it for a moment ,

The data travels through more than just a cable , it has to come through the device port on the source and into the device port on the sink , correct ?

All mounted to the boards with at least a 90 degree connection , the circuit board itself is probably multilayered with at least some connections between layers doing a 180 degree twist. Ask yourself how the Data copes with that ?

Really , Data having trouble navigating bends is ludicrous, and you have to seriously question the credibility of anyone who comes out with stuff like that !

By the way , Ive read a lot of his posts on Cebit pro , most skewed towards cable sellers , and as someone who has no interest in selling cables , I can tell you that most of his posts concerning HDMI cables are wildly inaccurate at best !
 
For the record , and to everyone in general , if you looking for information on HDMI the worst thing you can do is get it from a cable manufacturer/seller site.
They are shall we say , Liberal with the facts !

QED spends a page or so trying to convince you there is no such thing as a digital cable ( what tripe ... ). And qualify this with a " We believe " on the page.

Blue jeans go down the route of " HDMI is a shambles of an interface , but we have to make the most of it ....and with our cables.... " and so on ....

They simply cannot be trusted , and the information on these sites concerning HDMI is only good for parting the gullible and their money !
 
QED spends a page or so trying to convince you there is no such thing as a digital cable ( what tripe ... ). And qualify this with a " We believe " on the page.

I was just scanning the QED website looking for this article (I could do with a laugh) and found some classic material in their glossary. I quote: "Air is probably the most stable and effective insulator known."

Errr - no, it isn't. Not even close. PVC is a better insulator than air, as is teflon, silicone, glass, nylon, paper...air breaks down and conducts at a much lower voltage than any of those.

If they get something as elementary as that wrong, it really does call into question everything else they claim!
 
It would be very easy to just ridicule the part in bold , I wont though , and try to get you to just think about it for a moment ,

The data travels through more than just a cable , it has to come through the device port on the source and into the device port on the sink , correct ?

All mounted to the boards with at least a 90 degree connection , the circuit board itself is probably multilayered with at least some connections between layers doing a 180 degree twist. Ask yourself how the Data copes with that ?

Really , Data having trouble navigating bends is ludicrous, and you have to seriously question the credibility of anyone who comes out with stuff like that !

By the way , Ive read a lot of his posts on Cebit pro , most skewed towards cable sellers , and as someone who has no interest in selling cables , I can tell you that most of his posts concerning HDMI cables are wildly inaccurate at best !

Andy,

you're not correct on this point, placing an extreme kink in an HDMI cable can cause problems with its characteristic impedance at that point due to physical displacement of conductors, dialectric and/or screens. This results is greater signal degredation, which may result in problems recovering the data, particularly if you are altready runnign at the limits of the cable.

John.
 
Andy,

placing an extreme kink in an HDMI cable can cause problems with its characteristic impedance at that point due to physical displacement of conductors, dialectric and/or screens. This results is greater signal degredation, which may result in problems recovering the data, particularly if you are altready runnign at the limits of the cable.

John.


And indeed the same is true for co-axial cables and optical-fiber cables.
(In an optical-fiber which is being bent, the bending strain affects the refractive index of the fiber in the region of the bend)


Alan
 
Andy,

you're not correct on this point, placing an extreme kink in an HDMI cable can cause problems with its characteristic impedance at that point due to physical displacement of conductors, dialectric and/or screens. This results is greater signal degredation, which may result in problems recovering the data, particularly if you are altready runnign at the limits of the cable.

John.

Ive never seen anything of the sort , and dont buy it for a second , as I said , its common sense to avoid bends in cable , but for mechanical reasons only ,as most of the above quote covers , however suggesting an electrical signal in an otherwise undamaged cable has trouble with bends is laughable, you cannot deny that.

Optical has its own issues , refractive index being unique to a interface that uses light as a medium , but were not talking about optical here, were talking about HDMI.
 
Ive never seen anything of the sort , and dont buy it for a second , as I said , its common sense to avoid bends in cable , but for mechanical reasons only ,as most of the above quote covers , however suggesting an electrical signal in an otherwise undamaged cable has trouble with bends is laughable, you cannot deny that.

Optical has its own issues , refractive index being unique to a interface that uses light as a medium , but were not talking about optical here, were talking about HDMI.

Andy,

an HDMI cable is designed to carry a signal in the range of several GHz, to do this the conductor, dialectric and screening all work together to give the cable a required set of transmission line characteristics. These characteristics are sensitive to changes in the geometry of the cable e.g. a sharp bend of kink will result in signal degredation. This is not laughable it is simply the result of transmission line theory ;)

I've seen examples of this in the office at work where peopel have stood furniture on or bent DVI cables, the cables have stopped working for higher resolutions (often permenently!).

John.

PS - not sure what you've got against blue jeans, everything they say about HDMI cables is technically accurate and they specifically make no claims about improving image quality like other vendors.
 
Here you go

http://www.lenbrookamerica.com/images/downloads/HDMI_Cables.pdf

The half truths and spin printed in that document is beyond belief , however I have no doubt that unsuspecting non technical buyers have been conned by it.

Hmmmm - I actually agree with the notion that "there is no such thing as a digital cable" in the sense in which they use it - HDMI cables do carry an analogue representation of a digital signal.

That said, comments like "Error is expected. By some more cleverness, a certain amount of error can be recovered. But why tolerate error in the first place? It is better to use HDMI cables with sufficient headroom to lower the error threshold." do beg the question as to exactly why it is better to avoid errors than to recover from them, given that the net effect is the same. I notice they don't attempt to explain why it should be better to avoid errors - it just seems to be presented as a basic truth, which it clearly isn't. Reminds me of the reasons given for all manner of CD tweaks in the early days, whereby they "made the error correction work less hard"...
 
Andy,

an HDMI cable is designed to carry a signal in the range of several GHz, to do this the conductor, dialectric and screening all work together to give the cable a required set of transmission line characteristics. These characteristics are sensitive to changes in the geometry of the cable e.g. a sharp bend of kink will result in signal degredation. This is not laughable it is simply the result of transmission line theory

I've seen examples of this in the office at work where peopel have stood furniture on or bent DVI cables, the cables have stopped working for higher resolutions (often permenently!).

All of which falls under the scope of mechanical damage , I am specifically responding to the above comments about " HDMI perfers to travel in straight lines " etc etc , Which is nonsense ... also , as I asked above , what about the on board sockets that you plug the cables into , wheres the transmission lines there ? They are bare pins terminated in the board for the most part ?
 
HDMI is a digital signal format, developed primarily as a platform for the implementation of HDCP (High Definition Content Protection) to prevent consumers from having complete access to the contents of high-definition digital recordings. As one might expect from a standard that was developed to serve the content provider industries, rather than the best interests of the consumer, HDMI is something of a mess. The signal is not robust over distance because it was designed to run balanced when it should have been run unbalanced (SDI, the commercial digital video standard, can be run hundreds of feet over a single coax without any performance issues); the HDMI cable is an unnecessarily-complicated rat's-nest arrangement involving nineteen conductors; switches, repeaters and distribution amplifiers, by virtue of this complicated scheme, are made unnecessarily expensive; and the HDMI plug is prone to falling out of the jack with little more than a light tug. As more and more manufacturers move to implement HDMI on more home theater devices, however, it falls to the consumer to try to make the best of this dubious and poorly-thought-out standard.

Concerning Blue Jeans , this is the part from the HDMI page that Im referring too .....

Amazingly , considering the comments above , the majority of people are able to get perfect results with cables costing less than a tenner , something my recent lab tests proved beyond a doubt , hardly a " dubious and poorly thought out standard " now is it.

And concerning the comments about balanced versus unbalanced , well we could start a whole other thread about that , needless to say the comments in here are incorrect for many many reasons.
That whole paragraph is designed to sow doubt in the buyers mind about cables .... and is again an example of the kind of spin one finds only on cable sites.
 
Hmmmm - I actually agree with the notion that "there is no such thing as a digital cable" in the sense in which they use it - HDMI cables do carry an analogue representation of a digital signal.

QED's specific phrasing in this case is to fool a buyer into thinking that the digital signal is prone to the same losses as analog , whereas the truth is anything but , the signal is not an analog representation of the content , something they neglect to mention , and as such all that matters is that the levels between logic 1 and logic 0 are distinct , no matter how much noise or interference it takes , as long as the levels are distinct the data remains intact and consequently the content remains intact.

Its called high interference immunity , and is what distinguishes a digital cable from a non digital one. Its only the difference between levels that matters , something not mentioned here , indeed something that is notable by its absence.
The content is clearly meant to deceive.
 
Optical has its own issues , refractive index being unique to a interface that uses light as a medium .



That is not strictly correct. The refractive index of a transmission medium is just the ratio:

(the phase velocity of a wave in a reference transmission medium) / (the phase velocity of the wave in the transmission medium under discussion)

This definition applies to any wave transmission, including sound waves and electromagnetic waves of all types.


Alan
 
Concerning Blue Jeans , this is the part from the HDMI page that Im referring too .....

Amazingly , considering the comments above , the majority of people are able to get perfect results with cables costing less than a tenner , something my recent lab tests proved beyond a doubt , hardly a " dubious and poorly thought out standard " now is it.

And concerning the comments about balanced versus unbalanced , well we could start a whole other thread about that , needless to say the comments in here are incorrect for many many reasons.
That whole paragraph is designed to sow doubt in the buyers mind about cables .... and is again an example of the kind of spin one finds only on cable sites.

Not sure why you feel the need to jump to the defense of HDMI, particularly given that many people around here have had a disproportionate number of problems with things like HDCP. It is a fact that HDMI could have been better, afterall you only have to look at Display Port to see what a good implementation of a similar style interface looks like (particularly re the unnecessary rats nest).

The fact of the matter is that HDMI is not a well thought out interface, if it was threads like this would be much less common, and the crux of bluejeanscable's comment is that we already had a digital interface standard that worked over distances an order of magnitude greater tha we're ever likely to see passive HDMI work over with nothing but a bog standard peice of 75Ohm coax. Note that I beleive their comment on twisted pair relates to the difficulty associated with accurately controlling impedance in such an arrangemt, this is an accurate statement that is particularly pertinent to transmitting very high frequency data over long distances.

At the end of the day I find it hard to see why you view accurate information as spin, particularly when its on the sight of a company that offers the same value for money as BJC.

John.
 
Not sure why you feel the need to jump to the defense of HDMI,

Im not defending HDMI per se , Im defending non technical consumers from conmen if Im doing anything.

The fact of the matter is that HDMI is not a well thought out interface, if it was threads like this would be much less common,

I disagree , and with literally reams of bit error rate data to back it up I have the best of reasons to disagree , it works well enough for its intended purpose , as millions can testify , and the only reason threads like this are common is purely down to dishonest cable sellers full stop.

The only reason these threads get started is because of some shyster saying their ludicrously expensive cable is better than everyone elses because ... etc etc etc .... something which does not hold true in the digital domain.
Once the cable is carrying binary data , its a digital cable , and all that has to happen is that the data at source matches the data at sink , once that happens the cable has done its job as well as it possibly can , and that can be proven to be undeniably true in the case of the vast majority of HDMI cables , regardless of how much they cost.

Regardless of the interface being SDI , Display port , or whatever , I Believe the cable sellers would pull the same con regardless of the digital cable involved. I am sure that if the interface in question was SDI the cable sellers would still pull some technical half truth out of the bag and claim deeper blacks , better colours , more bandwidth etc for their product.

Its a cash cow these people are not willing to let go of on the switch over to digital.
 
I disagree , and with literally reams of bit error rate data to back it up I have the best of reasons to disagree , it works well enough for its intended purpose , as millions can testify , and the only reason threads like this are common is purely down to dishonest cable sellers full stop.

Although there is no accounting for the dishonesty of certain cable companies it remains undeniable that a better designed standard would have removed much of the ambiguity that these people pray on, this is particularly relevent to longer cable runs where HDMI simply becomes flakey.

The only reason these threads get started is because of some shyster saying their ludicrously expensive cable is better than everyone elses because ... etc etc etc .... something which does not hold true in the digital domain.

Naturally there is no account for fools and those who just plane lie.

Once the cable is carrying binary data , its a digital cable , and all that has to happen is that the data at source matches the data at sink , once that happens the cable has done its job as well as it possibly can , and that can be proven to be undeniably true in the case of the vast majority of HDMI cables , regardless of how much they cost.

BJC explicitly state on their site that if a cabel works then you won't get a better picture (see section on myths) and to be honest what is annoying me here is that you have decided to pigeon hole what is basically an honest company with the likes of QED, Chord, Wirelworld etc (seriously, look at the what Chord say on their website!).

Regardless of the interface being SDI , Display port , or whatever , I Believe the cable sellers would pull the same con regardless of the digital cable involved. I am sure that if the interface in question was SDI the cable sellers would still pull some technical half truth out of the bag and claim deeper blacks , better colours , more bandwidth etc for their product.

Its a cash cow these people are not willing to let go of on the switch over to digital.

HDMI's ambiguity at longer distances play into the hands of these people, remove that ambiguity, as the likes of SDI etc do by virtue of actually working at most distances encountered in HC without problems and you go a long way to disarming the marketing departments of these companies.

John.
 
Any fool can criticize, condemn, and complain -- and most fools do. (Barker Bob) /// learn to ignore :thumbsup:
 
Any fool can try and rip people off with spin/nonsense and only fools will listen to it :thumbsup:
 
This thread is a strange combination of good facts mixed with misguided attacks on two retailers who actually sell at reasonable prices and, in the case of BlueJeans website, one of the best and most honest explanations of the HDMI minefield.

Nothing I've seen here changes my view that directing people to BlueJeans to read up on HDMI is a good thing and that the prices there and at UKHDMI remain realistic and fair.
 
Andy, so, for average joe here, I'd be better buying a non gold plated non this and non that for £4 rather than fork out £40 for a gold plated, high performance etc, etc, cable?

Comet had one yesterday at £200. I told the guy that it was 4 times as much as the dvd player its going to be connected to. He then said that he could have a word with the manager to see if he'd knock a few quid off! I then saw that it was 6m long and told him I didn't need that as everything was together. He said I would be better with a longer one (!) as it would give me the flexability to move things around in the future. I left having a giggle to myself and admiring the guys straight face while he tried to convince me. Didn't buy anything. Cheapest he had was £30 but he said it wasn't worth the packaging it came in.

Then I came back and read this thread. Looks like its the first good decision I've made in a long while. Asda have a Philips one at £9 which looks fine. Think I'll go get it today.

Thanks fella's.
 
Andy, so, for average joe here, I'd be better buying a non gold plated non this and non that for £4 rather than fork out £40 for a gold plated, high performance etc, etc, cable?

Yeah thats pretty much correct , Gold on a HDMI is just bling , if you like the look of it then fine , but it does nothing to help the signal ,

Recommending a longer cable over a shorter one , thats the first time Ive heard of that , these guys are getting more outrageous by the day , although 6 meters would probably be fine , if theres one area where HDMI does actually fall down its with long runs.

When we ran the test we split the cables into 3 categorys ,
Up to 5 meters ,
Between 5 and 10 meters ,
15 meters or more , ( we didnt get any between 10 and 15 at the time )

Only the 15 meters or more showed problems with attenuation , and it was just attenuation, the majority worked fine when boosted.
 

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