So you’ve just spent a bundle on a new HDTV or a home theater system. You’re about to head for the register, and the salesperson suggests that since you’ve invested so much in your system, it needs expensive cables to give you optimal performance.
If visions of rust-proofing and high-end floor mats come to mind, you may be on the right track. Ever since Monster Cable started operations decades ago, the myth that “more expensive cables are better” has been heavily promoted to the A/V consumer. It’s true that we should all avoid poorly-made cables, but whether there’s anything out there that will give you better performance than, for example, Radio Shack’s “gold” cables, has yet to be proved. Years ago, Stereo Review magazine (now Sound and Vision) did a true double-blind study of premium cables. A few of their testers discerned a very slight difference between cables, but no improvement was detected.
But that’s all old history, we’re told, because those cables were “analog.” With new “digital” cables (e.g., HDMI), quality is more important than ever. Indeed, the term “digital” sounds more complicated and less familiar, so we’re inclined to accept what we’re told. Still, knowledge is power, so let’s examine the facts.
In actuality, all signals are analog in nature. So all signals need a reasonably good wire to travel un-degraded from point A to point B. True analog signals travel as a continuously changing voltage, which must be faithfully reproduced on the far end of the cable. Equipment can tolerate a small amount of degradation, but significant disruptions will be reproduced, uncorrected, in your speakers.
Digital signals also travel as a continuously changing voltage, but the signal alternates between two levels; one near the maximum voltage, and the other near zero. The receiver samples the signal only when it is known to be stable, and measures only whether the signal is above or below a middle threshold. A high voltage is considered a “1”, and a low voltage is considered a “0”. Below are two traces showing consecutive 0s and 1s. Both would produce equivalent data.
As long as the digital signal isn’t degraded so much that the 0/1 measurement is made in error, the receiver will receive the transmitted signal with no imperfections. Even better, most signals include extra data bits used to check and reconstruct the transmitted data, so that even if an occasional 0/1 is received incorrectly, it can usually be fixed, again resulting in a perfect signal.
A higher quality cable may increase the difference between the high and low voltages, but anything better than “good enough” does not provide an improvement. An acceptable 0 or 1 (upper trace) and an exemplary 0 or 1 (lower trace) convey the exact same information.
So how do you know if your cable is good enough? Analog signals degrade gracefully. A slightly-damaged analog signal can sound very similar to a good one, such that only trained ears might hear a difference. However, with a digital signal, the effect of even a few uncorrected 0s and 1s is likely to create obvious distortion of picture or sound. Thus, if your HDMI signal sounds and looks good, it is most likely just fine.
Still, some cable manufacturers promote features that can be of little benefit. It’s not that these features don’t improve the wire, but once the wire is “good enough,” making it even better really doesn’t provide any benefit. A car that can travel 140mph may not benefit someone who never drives over 60.
Two features, lower-gauge (e.g., thicker wire) and twisted-pair, have some benefit in certain situations. For speaker wire, many authoritative sources provide tables for distance vs. gauge. However, exceeding the recommended gauge provides no further advantage. Twisted pair is already common in digital cables (e.g. HDMI). It’s appropriate for long multi-room runs, and can help reduce interference for line-level analog signals (like the connections between your audio components and receiver). But don’t bother upgrading unless you’re actually overhearing someone’s CB radio.
Oh please Mr. Williams, I would soooo much like to learn from you! Can you please tell me where in aerospace we’re using copper wire of “high purity (99.999% pure) and free of oxygen crystals”? I’ve been asking all of my aerospace engineering buddies and they all simply laugh at me, but I’m simply very sure you know soooo much more about aerospace than they do! I would really like to show them a real example, especially since aerospace has done soooo much work in this area and nobody seems to know about it.
There is considerable confusion about the performance of cable. It should not be about price. It should be about value.
Quality cable is not recycled copper. It is high purity (99.999% pure) and free of oxygen crystals or barriers within the wire.
One of the biggest advances (primarily by the military and aerospace industries) in recent years has been in material science.
The performance of superior purity, oxygen free wire is
scientifically verifiable.
Perhaps; rather than rant or give an opinion, one may wish to LEARN.
Please go to: www.analysis-plus.com
A most revealing element of home theater (video) is that
in place of audiophiles claiming they can hear a difference,you can see it.
@Errol:
We’re not in denial, we just don’t want to be ripped off! Go ahead, conduct a double blind study comparing a $1.98 1 meter HDMI cable to a $100(?) 1 meter Monster cable. Prove there’s any repeatable results that show the $100 cable visibly (or audibly) superior to the $2 cable.
John - I suppose on one hand it depends on the speaker, on the other - the length is only maybe .5-1 foot for all but the biggest speakers. The issues are less for short lengths. (I know, a very simplistic statement).
I would expect HTIB system to have wire the thickness of a rat hair. And high quality speakers maybe 12 gauge - but at that, probably not with a thick plastic jacket - no real need - it is protected in the box so there is no physical damage worry.
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Nice! And how much is the tab?
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this article doesn’t do anybody justice. if you are talking about lo-fi or mid-fi equipment (which this is what it sounds like), then the weakest link isn’t the cable but the other equipment. if you are talking hi-fi equipment, then the weakest link could be the cable. there are all types of wire that is used by hi end cable manufacturers, thin/thick, solid/multi strand, silver/copper/hybrid, etc… there is a difference between cables at the hi-end. go to a hi-end store and have them demo them for you on a nice hi-fi system. i have, my wife has, my friends have and they all have been able to hear the difference. maybe not all are better sounding, this isn’t what the article talks about, but there is a difference. ask yourself, why do so many vendors make 2-way speakers? are you saying that a $4000 pair of 2-ways is a rip-off compared to a $200 2-way with the same size individual speakers? how about different preamps? amps? digital sources? why would a $30k cd player sound any better than a $60 wal-mart special cd player? they both read 0’s and 1’s don’t they?
most people can hear the difference but do they want to pay the difference? that is the real question.
i’m waiting for your next article on comparing a porsche gt2 to a toyota prius: why the big difference in price? they both have 4 tires,motor, seats,etc… there is a difference but most people don’t or can’t spend that much $$$ on a porsche gt2.