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Why you should never pay more than $10 for an HDMI cable (Infographic)

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Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#61

Post by lkjhgvbnm »

ghshephard wrote: post #58
matwood wrote: post #29

Earlier quoted context omitted.

I think the point of the "either works or it doesn't" is a comparison versus analog. With an analog signal you could get slightly better results by getting better cables (or worse with worse cables). If you have a poor digital cable it flat out doesn't work. If the cable you're using works, buying a more expensive cable isn't going to make it work any better. Either the 1s and 0s made it from the source to the destin…

Clearly you've never had an Ethernet Cable that got caught in a door. Or was terminated poorly. Or doesn't have the insulator sheath under the crimp. Or run parallel to a set of Florescent light ballasts. All of these events can reduce performance on Ethernet without causing it to fail outright. There is a reason why every single TIA/EIA 568 cable plant is carefully tested for things like Near End Cross Talk (NEXT),…

But did you use audiophile, linear crystal aligned cables? And did you install them the correct way round? https://usa.denon.com/ProductDetails/3429.asp

Presumably on ethernet you have to decide if you want the Tx or Rx signal to have the extra digital nuance?

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#62

Post by ErrantX »

wwalker3 wrote: post #54
matwood wrote: post #29

Earlier quoted context omitted.

I think the point of the "either works or it doesn't" is a comparison versus analog. With an analog signal you could get slightly better results by getting better cables (or worse with worse cables). If you have a poor digital cable it flat out doesn't work. If the cable you're using works, buying a more expensive cable isn't going to make it work any better. Either the 1s and 0s made it from the source to the destin…

That's still not correct. For HDMI in particular, there's no error correction at all on the video data (though there is on the audio and control data). So if one bit gets flipped in the video data as it goes through the cable, you're going to see that wrong bit on screen. You'd have to have an insanely high bit error rate for your eyes to notice it, but it's there, and it gradually gets worse as the error rate increa…

Indeed. However it uses TMDS [1] which is a "blind mans" error reduction technique.

1. http://en.wikipedia.org/wiki/Transition_Minimized_Differenti...

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#63

Post by pcarmichael »

smackfu wrote: post #3

It's rare to see even a $10 one at retail. Often the lowest priced one is $20-25, and there are a bunch of $40 options. And not even talking about Monster which this article is singling out.

At the local Fry's (in Austin), there is a section of HDMI cables by the TVs and DVD/Blu-ray players. Cheapest in that section is about $20-$25 as you mention. However, over on the other side of the store, near the computer components, there is a section full of cables (coax, etc.). They have HDMI cables over there too - for ~$10 or so. I guess in some stores you just have to know where to look.

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#64

Post by matclayton »

The Reason to buy a really expensive HDMI Cable.

There is only one "good" (dubious) reason to by a really expensive cable, and that is for range. There is a performance differences between the cheap and gold cables, due to the different conductivities. However over short distance this isn't observable, as the receiver will correctly interpret the digital signal even though there is no noise on the line, this is the beauty of digital signals. It is there or it isn't, and with decent ECC on the line, which I'm assuming HDMI has, even with a fair bit of degradation it wont be an issue.

However as you extend the cable the signal with degrade at a different rate depending on the quality of the cable, and eventually you will reach a distance where the digital signal even with ECC is lost, and it will no longer work. With a higher quality cable this range is greater, (we are talking of ranges in the 10's -> 100's of meters), certainly no issue for a normal TV setup, and you would have to question why you even needed such a long cable to start with, move your source/receiver closer to each other.

The only other factor which might show up is the sensitivity and power of the transceivers, and you might find a cable of 100m works on some gear and not on others, but if you do you really are using the wrong tool for the job, go buy a optical repeater :)

I'm guessing on distances here, but you get the idea, I use to work in high frequency data transmission systems, and have no idea of the detailed specs of HDMI but should give you an idea.

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#65

Post by tedunangst »

Tichy wrote: post #53
micks56 wrote: post #39

Earlier quoted context omitted.

I think your understanding of cables is off. All signals are analog. Every single one. (Actually, I take that back. With the exception of quantum computers, to date, all signals are analog). A "digital" cable doesn't just work or not work. It is possible to receive spurious bit errors for many reasons. For example, you turn up the volume to your awesome surround sound speakers, which causes more current to flow throu…

There is this weird thing called error detection/correction.

which HDMI doesn't do.

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#66

Post by tedunangst »

axod wrote: post #45
micks56 wrote: post #39

Earlier quoted context omitted.

I think your understanding of cables is off. All signals are analog. Every single one. (Actually, I take that back. With the exception of quantum computers, to date, all signals are analog). A "digital" cable doesn't just work or not work. It is possible to receive spurious bit errors for many reasons. For example, you turn up the volume to your awesome surround sound speakers, which causes more current to flow throu…

>> "It is possible to receive spurious bit errors for many reasons." Surely that's why there's error correction layered on top? Instead of arguing about what might happen, why not find an HDMI device that'll show you how many unrecoverable bit errors it has detected in the stream... Can't be that hard to do. If my hard disk can send data over a tiny crappy unshielded cheap USB cable without a single bit error, I'd be…

HDMI doesn't do error correction for video.

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#67

Post by wwalker3 »

ErrantX wrote: post #62
wwalker3 wrote: post #54

Earlier quoted context omitted.

That's still not correct. For HDMI in particular, there's no error correction at all on the video data (though there is on the audio and control data). So if one bit gets flipped in the video data as it goes through the cable, you're going to see that wrong bit on screen. You'd have to have an insanely high bit error rate for your eyes to notice it, but it's there, and it gradually gets worse as the error rate increa…

Indeed. However it uses TMDS [1] which is a "blind mans" error reduction technique. 1. http://en.wikipedia.org/wiki/Transition_Minimized_Differenti...

Totally true. HDMI takes many steps to try to reduce errors to a reasonable rate. In practice, this rate is usually low enough to ignore, even with cheap cables.

I was just making the point that there is indeed a progressive degradation in image quality with increasing error rate, even in HDMI.

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#68

Post by Tuna-Fish »

Sam_Odio wrote: post #24

Even better: An electromagnetically shielded, gold plated optical audio cable. Sold at Sears [1]. I stopped buying cables retail a long time ago. My favorite supplier: RiteAV. They're (IMHO) the Amazon of cables. Huge selection, modest prices [2], and great customer service [3]. 1. http://www.sears.com/shc/s/p_10153_12605_05750807000P?vName=... 2. HDMI cables start at $3.50 - http://www.riteav.com/hdmi-cables-c-141_1…

[1] made me hysterical for a few minutes. I know this old audiophile who insisted on buying the gold-plated kind when I helped him set up his home theater. I literally spent hours trying to convince him that it didn't matter, but apparently learned behavior just beats logical arguments and evidence.

I think the reason there is a market for these kind of ripoffs is that back in the analog era the quality of cables really mattered, and that's when the people who buy these learned what they know of tech. I don't think it gets harder to learn new ideas as you get older, but instead unlearning the ones that have worked for you gets progressively harder the longer you have had them. I only hope I can be more rational when I get older.

Re: Why you should never pay more than $10 for an HDMI cable (Infographic)

#70

Post by jcromartie »

wwalker3 wrote: post #54
matwood wrote: post #29

Earlier quoted context omitted.

I think the point of the "either works or it doesn't" is a comparison versus analog. With an analog signal you could get slightly better results by getting better cables (or worse with worse cables). If you have a poor digital cable it flat out doesn't work. If the cable you're using works, buying a more expensive cable isn't going to make it work any better. Either the 1s and 0s made it from the source to the destin…

That's still not correct. For HDMI in particular, there's no error correction at all on the video data (though there is on the audio and control data). So if one bit gets flipped in the video data as it goes through the cable, you're going to see that wrong bit on screen. You'd have to have an insanely high bit error rate for your eyes to notice it, but it's there, and it gradually gets worse as the error rate increa…

I've had this happen. You see what are called "sparkles" when you get a lot of failures (and it truly looks like sparkling glitter on your TV). It turned out to be the TV's connector more than the cable itself. The same $4 cable worked fine on a replacement set.
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