In addition to my answer above Derek, I'll add issues of psychology.
A man's credentials as a technician, reviewer, installer, or years in the industry do not matter. His REAL experience listening and viewing interconnects DO matter.
If the man is set in his views that either he always will hear or see differences or improvements between cables, than it is his psychology, and not reality, speaking. And if he tells you that there are no differences between audio and video interconnects, it is the same.
A Chevy will get you there. So will a Ferrari. If you can't afford a Ferrari you will, sometimes, actually believe that there is NO reason to spend $200,000 for a Ferrari, or that the improvements you see, feel, or believe regarding the quality of one over the other, does not warrant the higher price. In the case of a car, one can say we are talking values, not value. There is a huge distinction between one's values, and the objective value of the subject matter.
Objectively, as well as subjectively, many people have an huge investment in their belief systems. Objectively and subjectively, in the highest quality systems -- as in a high quality microscope -- one can hear and see dramatic differences between interconnects. But not always...just most of the time.
There are levels of qualitative improvements between cables that can be repeatedly demonstrated to anyone with an open mind.
If a man has never heard, let's say (and I'll choose one lesser known but a very competitive and successful brand) NORDOST video or audio cables, one can actually continue to believe that his Best Buy cables...even by a major well known manufacturer -- is good enough, or the best. For example, a Nordost component video interconnect, if I remember correctly, costs about $500. To many it is insanely priced.
So the way I see it....I mean "see" it....is that is is 10% of the price of your $5000 large screen TV. Or about 15% of your $3500 large screen TV. What if I told you that it can improve your picture quality 30%? Even after calibration!
You'd probably not believe me and believe the gents on this post who -- never having experienced it for themselves -- tell you to just go ahead and buy the $19 cables.
No I say. Order the high priced spread with return privileges...see for yourself...and improve your enjoyment of the hobby.
The fact is, meeting the specs is NOT enough. The impedance terminations of these cables are critical. Close enough is not enough.
The sad truth about quality is that it costs money. There are no free lunches, no free health care, no free drugs. Someone has to pay for all of those. There are consequences to be paid for short cuts to quality (your Ferrari will beat the pants off your Chevy and the girl sitting next to you just may be hotter than the one sitting next to the guy in the Chevy...) All steaks do not taste the same; all suits do not feel the same, nor fit the same; all amplifiers do not sound the same; all hi def TV displays do not have the same quality of video processing.
All cables do not have the same performance because in fact they do not have the same transmission capability...
...because we cannot measure all things. We, well, some of us, just believe that we can. And it is what you have not yet measured that makes the difference...especially if someone has measured and identified what makes the important differences. Ferrari has. But it costs money to give you the F-048's performance. Sorry, but reality does not care what we think...only what is.

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