Video Benefits of WW HDMI Cables

[mbovaird]

Originally Posted by Thebenz

I agree with the comment that different HDMI cables do not change anything. There is lengthy discussion on this all over the internet proving the cable does not matter with the picture. One other thing to consider with optics is that the human eye cannot distinguish resolutions beyond a certain distance depending on the size of the screen.

+1.

[uwbadger]

Originally Posted by mbovaird

+1.

+1

ayre dx-5, kxr, mxr, Vandersteen 5A

[TommyC]

The difference is more noticeable if you have bigger screen and/or need longer length. It will be difficult to notice the difference if you use a 1.0M cable on a 50" screen.

[Masterlu]

Originally Posted by TommyC

The difference is more noticeable if you have bigger screen and/or need longer length. It will be difficult to notice the difference if you use a 1.0M cable on a 50" screen.

Agreed... It was a very noticeable improvement on my MVP881 going from a 2.0M Silver Starlight to 2.0M Platinum Starlight on my 120" screen.

[Face]

No difference here either.

[Researcher]

Is there an improvement in audio or video performance in upgrading from a 16 to 24 conductor cable?

Thanks.

[catmonv]

My belief is that changing of the hdmi cables would not give you any change with the video pic. Once your tv set is calibrated to get the blackest black and the whitest white, it will not go past that. I would suggest to use your money for video calibration rather than HDMI cables in getting the best video pic.

[uwbadger]

Originally Posted by Masterlu

Agreed... It was a very noticeable improvement on my MVP881 going from a 2.0M Silver Starlight to 2.0M Platinum Starlight on my 120" screen.

This may be true but not supported by others blinded tests

As a scientist I am very intrigued by cables and power cords.

Why don't people set up blinded studies. It would be very simple to do with video. Have someone switch cables 10 times and see if you can tell. If you are not correct nearly every time then it is salesman's smoke.

ayre dx-5, kxr, mxr, Vandersteen 5A

[MyPal]

The digital signal over HDMI can degrade, in purely electrical terms, quite a bit over a distance run, but if at the end of that run the bitstream can be fully and correctly reconstituted, it doesn't matter what degradation the signal suffered--once that information is reconstituted at the receiving end, it's as good as new. That's a big "if," however.

Ideally speaking, digital signals start out as something close to a "square wave," which is an instantaneous transition from one voltage to another; these transitions signal the beginnings and ends of bits. (In practice, such transitions aren't strictly possible, and trying to achieve them can generate harmful noise; consequently, high-order harmonics are usually filtered out which results in the wave starting out squarish but not-quite-square.) A square wave, unfortunately, is impossible to convey down any transmission line because it has infinite bandwidth; to convey it accurately, a cable would have to convey all frequencies, out to infinity, all at the same level of loss ("attenuation").

What happens in any run of cable is that a digital signal starts out looking relatively nice and somewhat square, and comes out the other end both weaker and rounded-off. The transitions that mark the edges of bits get smoothed and leveled to the point that, far from that ideal square wave, they look like relatively gentle slopes. Portions of the signal lost to impedance mismatch bounce around in the cable and mix with these rounded-off slopes, introducing an unpredictable and irregular component to the signal. Crosstalk from the other pairs in the HDMI bundle also contribute uneven and essentially random noise. As a result, what arrives at your display doesn't look very much like what was sent. Up to a point, this degradation along the HDMI cable won't matter; the bitstream gets accurately reconstituted, and the picture on your display is as good as the HDMI signal can make of it.

But when it starts to fail, it starts to fail conspicuously and dramatically. The first sign of an HDMI signal failure is digital dropouts--these are colloquially referred to as "sparklies"--where a pixel or two can't be read. When these "sparklies" are seen, total failure is not far away; if the cable were made ten feet longer, there's a chance that so little information would get through that there would be no picture on the display at all.

The shame with this horrid format is that, with HDMI, this is prone to happen at rather short lengths. When DVI was first introduced (same basic encoding scheme, same cable structure, but a different connector from HDMI), it was hard to find cables that were reliable in lengths over 15 feet. The fact that these multipin cables aren't economical to manufacture in the US and so were being produced exclusively in China, too, didn't help; Chinese cable manufacturers are very good at keeping costs down, but not the best at keeping tolerances tight. Today, a good HDMI cable can be relatively reliable up to about 50 feet, but because different devices tolerate signal degradation differently, it's impossible to say categorically that a 50 foot cable will work; it's only possible to say that it will work with most devices.

The better quality the cable, the closer to an accurately bit perfect bitstream may be transmitted over distance.

[Glisse]

When it comes to seeing and hearing, often the wrong science seems to be invoked in debates.

Sight initiates via a bio-chemical process. Sound via a bio-mechanical process. Both initial processes result in generation of an electrical signal that is sent to the relative area of the brain. This electrical signal is then interpreted by the brain.

There is no scientific measure, in any field of science, for interpretation.

If person A interprets a change in vision, or sound, from a cable, but person B does not: who is right?

I believe the answer is neither are wrong. Yet it is human nature to assume that our own perceptions are the correct ones. Pity.

My own perception is that I don't see much difference between HDMI cables, but I hear quite a difference. But then my hearing is much better than my eyesight. What I do notice is that audio over HDMI doesn't sound all that great. However, I am far less aware of this when watching a movie. It seems my brain backs off on its interpretive powers for hearing when it is also busy interpreting visual signals.

Maybe I have a small brain

Perhaps also explains why, if I am trying to listen to very low level sound, I often tend to close my eyes. For me Starlight and Silver Starlight are great. For others I am sure generic cables or Platinum Starlight are just as great - vive la différence