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post #1576 of 1790

Note the word 'analogy'. What do you mean by an audio cable is 99.9999%, this statement in itself makes no sense. Percentage of what? Purity? For all intents and purposes a functioning audio cable is 100% and that is that, even if you were a bat. And regarding your statement about HDMI, that in fact is not true:

 

It is commonly stated that all HDMI cables are created equal because it is a digital signal. While this is close to the truth when the spec is followed, it's not always true. The one major thing that can really destroy your signal quality is the length of the HDMI cable. It's true that HDMI signals are digital, and digital signals are 1's and 0's. The problem is that there is no such thing as a 1 or a 0 in digital electronics. It is represented in various ways. Lack/Presence of a signal, a positively magnetically charged or negatively magnetically charged medium, voltage at a certain value, etc... For instance a hard drive stores data using magnetism. The signal stored is read against an expected value range. For instance a 1 can be stored at a signal strength of 10 (while a zero is -10). A signal strength of 9.6 will also be read as 1. This is how overwritten data can be recovered. While a hard drive will read something as a definite 1 or 0. The signal strength can be used (with the help of sensitive equipment) to approximate what the previously written value was.

Here is a chart from wikipedia detailing the phenomenon:

Analog signal:        +11.1  -8.9  +9.1 -11.1 +10.9  -9.1
Ideal Digital signal: +10.0 -10.0 +10.0 -10.0 +10.0 -10.0 
Difference:            +1.1  +1.1  -0.9  -1.1  +0.9  +0.9
Previous signal:      +11    +11   -9   -11    +9    +9

How does this relate to your HDMI cable? As the length of the cable increases, not only does the signal strength decrease but so does the differentiation between each subsequent bit. If the signal quality is so bad that the machine at the other end cannot tell where one bit starts and another ends, it can guess (based on the signal strength) an incorrect value. The resulting signal is still digital, is it not? And yet it is incorrect. A poorly constructed cable’s signal degradation is affected by this problem, while high-quality cables often have active boosters. Thanks to this the signal strength stays at values that can be properly read (as a 1 and a 0) and will not blend with their neighboring bits.

post #1577 of 1790

That's totally different from analog cables. It's a good analogy for digital audio cables, but not for things like headphone cables.

 

While any competently constructed analog cable is just fine, unlike HDMI cables there can be something in between a perfect signal and no signal. It's possible to cut off some of the high frequencies for example, some cables do this intentionally. It's not an all or nothing signal.

post #1578 of 1790
Quote:
Originally Posted by chewy4 View Post

That's totally different from analog cables. It's a good analogy for digital audio cables, but not for things like headphone cables.

 

While any competently constructed analog cable is just fine, unlike HDMI cables there can be something in between a perfect signal and no signal. It's possible to cut off some of the high frequencies for example, some cables do this intentionally. It's not an all or nothing signal.

My point is that, as an analogy whether the cable is analog or digital, default stock ones do what they should do with inaudible differences unless as you say there are cables intentionally designed to cut off high frequencies. Digital cables also 'degrade' in certain ways as stated above, but we are talking about minute differences same for audio cables. All I am trying to draw a parallel is that, you go out buy a HDMI cable it does the job. You go out and buy a stock cable that is not defect it does the job for audio.


Edited by uchihaitachi - 5/15/13 at 11:55am
post #1579 of 1790
Quote:
Originally Posted by uchihaitachi View Post

All I am trying to draw a parallel is that, you go out buy a HDMI cable it does the job. You go out and buy a stock cable that is not defect it does the job for audio.

That's not an analogy, it's a truism. Like "You buy coffee mug that isn't porous and it does the job for holding coffee". It doesn't inform, or explain anything that isn't self evident.
post #1580 of 1790
Quote:
Originally Posted by uchihaitachi View Post

My point is that, as an analogy whether the cable is analog or digital, default stock ones do what they should do with inaudible differences unless as you say there are cables intentionally designed to cut off high frequencies. Digital cables also 'degrade' in certain ways as stated above, but we are talking about minute differences same for audio cables. All I am trying to draw a parallel is that, you go out buy a HDMI cable it does the job. You go out and buy a stock cable that is not defect it does the job for audio.

Well any degradation bad enough in a digital cable that it causes flipped bits results in blatantly obvious artifacts or dropouts since it's pretty much corrupting the image/audio data. Anyone who has used a digital antenna knows what that's like.This is unlike analog, where for example you can get a static filled image but still be able to see what it is.

 

I do agree with your point that most stock cables do the trick regardless of whether they're digital or analog so sorry if I appear to be attacking that point, I just think the two kinds of cables are way too different to be compared.

post #1581 of 1790
If you read the previous posts carefully, I never compared the cables. Merely said that arguing about high end audio cables is equally ludicrous to say arguing about HDMI cables. The whole point is that they either do the job or they do not. Then a member said that signal in HDMI does not degrade so I provided him with an example where this actually happens.

The parallel I wished to illustrate was that people fighting to the bitter end about high end audio cables are like people in AV forums arguing about silver HDMI cables and how this magically improves resolution. Pointing out the fact that there is ZERO scientific basis in both camps. I hope that clears it up.
Edited by uchihaitachi - 5/15/13 at 12:46pm
post #1582 of 1790
Quote:
Originally Posted by uchihaitachi View Post

If you read the previous posts carefully, I never compared the cables. Merely said that arguing about high end audio cables is equally ludicrous to say arguing about HDMI cables. The whole point is that they either do the job or they do not. Then a member said that signal in HDMI does not degrade so I provided him with an example where this actually happens.

The parallel I wished to illustrate was that people fighting to the bitter end about high end audio cables are like people in AV forums arguing about silver HDMI cables and how this magically improves resolution. Pointing out the fact that there is ZERO scientific basis in both camps.

I said that HDMI is all or nothing, which it is, which is very different from audio cables. Of course the end result is the same since we can't perceive the effects that the audio cable causes anyways. 

 

The point isn't whether they do the job or not, but how easy it is to believe that they do not do the job. A working HDMI cable gives you a literally perfect signal. The zeros and ones will be correct, and if they aren't, you will most definitely know. 

 

It's not about scientific basis, it is about casual believability. While neither HDMI cables or audio cables really matter, it is a lot more believable for the average person that someone has golden ears that can hear the differences in cables, than it is that the zeros and ones of one HDMI cable are better than the exact same zeros and ones of another. 

post #1583 of 1790
Quote:
Originally Posted by ThinkAwesome View Post

I'm not a believer in audio cables, but unlike audio cables, an HDMI cable that works should have the exact same signal come in one side that goes out the other. It is a digital connection with an impressive amount of error correction. Either you get the signal for a picture that is 100% perfect, or you don't get a picture at all. HDMI cables making a difference is much harder to argue for than audio cables. 

 

If only this were true. In reality an HDMI cable has a very measurable impact on the signal, and how much damage it does depends on the cable design, and length.  The result may seem to be that it either works perfectly or it doesn't work at all, but the reality is there are a lot of in-between conditions where the connection works most of the time, but the picture blanks occasionally, or it works well with one pair of devices but not another.  

 

The reason is that the signals carried on HDMI are very high frequency data signals that depend on signal integrity so the sink device (usually a display) can decode everything.  Turns out, the actual picture signals are pretty robust.  You won't see big differences in picture quality with different HDMI cables. But the hand-shaking signals, HDCP and EDID, are actually a bit fragile, and can take a hit with a marginal cable.  The results can be unpredictable, and the problems actually quite difficult to isolate.  And cable quality can and does make a difference.

 

What's not true is that a good HDMI cable results in better color, image or sound, once we get past the absurd.  It's mostly a reliability and stability issue.

 

What is true is that the cost of an HDMI cable doesn't correlate to its ability to carry signals without damage.  Cheap HDMI cables can be just fine. So can expensive ones, and vice-versa. 

 

To compare HDMI to analog audio, we can say that the real difference is in the signals they carry.  Analog audio is very low frequency, very robust, and can be carried on cables without regard to impedance match until we try for some very long (miles) lengths.  HDMI carries signals in the RF region, where source Z, sink Z and cable Z all make a big difference and need to be matched.  Cable losses do impact the signal being carried, and need to be considered at the design phase.  The HDMI and analog audio signals are in two different worlds.  The cables they work with are completely different in design, of necessity.  The failure modes of each are very different as well, and the impact a cable can have on each is worlds apart.  

 

Please don't equate the two, they are not comparable.   

post #1584 of 1790

The thing with an HDMI cable is that when it isn't working properly, it's blatant.  With an audio cable it's easier for people to convince themselves of slight differences because it's not an all-or-nothing proposition like HDMI.

 

WITH THAT SAID... there are people who think a better HDMI cable will give them a better, more three-dimensional picture with deeper blacks and higher contrast.  So yeah, that nonsense exists in video as well.

 

The whole "I want my speakers to reproduce frequencies I couldn't possibly hear" thing doesn't really have a video comparison, though.  Nobody's clamoring for a TV that displays accurate ultraviolet and infrared.

post #1585 of 1790
Quote:
Originally Posted by sethsez View Post

The thing with an HDMI cable is that when it isn't working properly, it's blatant.  With an audio cable it's easier for people to convince themselves of slight differences because it's not an all-or-nothing proposition like HDMI.

The point I was trying to make before is that HDMI isn't all or nothing. It can be marginal, and the insidious part is, the fact that it's marginal may remain hidden, masquerading as working perfectly under some conditions, then randomly cause a glitch, dropout, or snow-burst.  This is a very sore point for me, as I work with HDMI on a daily basis, and have situations where I can set everything up, test it all, walk away, and get called back because something randomly glitched, often due to a marginal HDMI cable that didn't manifest itself for hours, even days.  I dearly wish it was all or nothing, but it's not.  It just acts that way to goof with our heads.  No, it's not a slight degradation in the blacks or image smear, or color shift, and yes it is a rather blatant problem when it finally does happen, it's just that it might not happen when you're looking.

 

Quote:

Originally Posted by sethsez View Post

WITH THAT SAID... there are people who think a better HDMI cable will give them a better, more three-dimensional picture with deeper blacks and higher contrast.  So yeah, that nonsense exists in video as well.

 

The whole "I want my speakers to reproduce frequencies I couldn't possibly hear" thing doesn't really have a video comparison, though.  Nobody's clamoring for a TV that displays accurate ultraviolet and infrared.

Agreed, those that think they see a difference, usually in a more expensive cable, will swear to it, but sadly, there's no good way to actually ABX an HDMI cable because it takes so long for re-sync.  Yes, it's nonsense.  And don't nobody get me a-rantin' on power conditioners...

 

But now we've gone and done it!  I can hear it already, "I read on a forum that with a better HDMI cable I can get more ultraviolet and infrared out of my TV.  I want one of them cables!  I know I can't actually see ultraviolet, but having it there maintains the purity and impact of the other colors."  Sheesh.  Did ya hafta??  oops, or did I?

post #1586 of 1790

Oh, I know that the problems with HDMI can be numerous, but the ways in which they manifest themselves aren't subtle.  You can't pretend you're seeing a slightly flatter image as the result of a defective HDMI cable.

 

And yeah, whenever I start getting too into audiophile stuff and start thinking "maybe there's something to this whole golden ears thing..." I just replace "hear 30,000khz" with "see ultraviolet" and go on my merry way.

post #1587 of 1790
Quote:
Originally Posted by sethsez View Post

Oh, I know that the problems with HDMI can be numerous, but the ways in which they manifest themselves aren't subtle.  You can't pretend you're seeing a slightly flatter image as the result of a defective HDMI cable.

 

And yeah, whenever I start getting too into audiophile stuff and start thinking "maybe there's something to this whole golden ears thing..." I just replace "hear 30,000khz" with "see ultraviolet" and go on my merry way.

 

Now, hearing 30 Mhz  would really be something ......

post #1588 of 1790
Quote:
Originally Posted by sethsez View Post

Oh, I know that the problems with HDMI can be numerous, but the ways in which they manifest themselves aren't subtle.  You can't pretend you're seeing a slightly flatter image as the result of a defective HDMI cable.

 

And yeah, whenever I start getting too into audiophile stuff and start thinking "maybe there's something to this whole golden ears thing..." I just replace "hear 30,000khz" with "see ultraviolet" and go on my merry way.

I was just reading an article on seeing ultraviolet:

http://www.extremetech.com/computing/118557-the-eyes-have-it-seeing-ultraviolet-exploring-color

post #1589 of 1790

Not sure if anyone has seen this already, but i found it to be a rather interesting read.

 

http://www.hometheaterhifi.com/volume_11_4/feature-article-blind-test-power-cords-12-2004.html

post #1590 of 1790
Quote:
Originally Posted by julian67 View Post


That's not an analogy, it's a truism. Like "You buy coffee mug that isn't porous and it does the job for holding coffee". It doesn't inform, or explain anything that isn't self evident.

I believe what he's trying to say, in terms of a coffee mug analogy, is that your coffee will taste the same irrespective of what mug is used as long as it isn't broke. In other words, it's like saying that an "upgrade snake oil gold reference coffee mug" will not make the coffee taste any better at all.

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