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Is this true? RCA vs Coax Cables

Old 02-03-05, 02:41 PM
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Is this true? RCA vs Coax Cables

Found this on another thread.....I said no, but I could be wrong:

"Actually, a regular rca cable will work just as well as a so-called digital coaxial cable. They're exactly the same thing. Buying an RCA cable labelled "digital coax" would just be a waste of money, especially if you've got a spare RCA cable laying around."


Also, if you take three RCA cables, is that the same as running component cables?
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Old 02-03-05, 02:55 PM
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I don't know about "work(ing) just as well" but they'll work. Same with component cables. Shielding and what types of metals and how they are braided and twisted and stuff does affect the quality, so it really depends on what your looking for and in what price range. I'm not coughing up a hundreds of dollars for a few feet of silver cable.
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Old 02-03-05, 04:13 PM
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Yes on the digital cable. Ignore the marketing crap. Ok, it is possible for noise or an impedance mismatch to cause problems, but in this application, it is highly unlikely to happen.

The component cable question is more tricky. Since the signal is analog, some degradation can occur with low-quality cables. However, the difference between an quality inexpensive 75ohm cable and a $$$$$ 75ohm cable are negligile for almost all home theater applications. If the cable is 75ohm and you don't live next to a 50kW am radio station, the cheap cable is probably just fine.

If you don't believe me, ask the professionals what they use. I guarantee you that it's not some overhyped Monster cable. Professional studios are wired with 75ohm coax from a reputible company such as Belden. The last time we bought a 1000 foot reel it was $75, or 7.5 cents a foot.

Last edited by Pistol Pete; 02-03-05 at 05:35 PM.
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Old 02-03-05, 04:33 PM
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Ok, it took awhile to find, but here is a test of using a coat hanger for a digital interconnect. 15 minutes of use yielded 0 Dolby Digital decoding errors.

*** "A delicate digital AC-3 signal originating from my $4500.00 Theta DaViD transport THROUGH A WIRE HANGER?!?" ***


Calm down Mrs. Crawford, yes, through a wire hanger... It'll work just fine...

Ok,

So if any of you followed the digital wire wars a while back you may recall that some people maintained that you absolutely, positively, NEEDED a 75 ohm digital cable to connect your DVD player to your pre/pro... Nothing else will do... Anything else, and you risk errors in the bitstream so bad, that they are not only uncorrectable but you will also lose that "smooth airiness on the highs; open and more believeable soundstage; (insert your favorite audiophile tripe here)" and that basically the more money you spend on a digital cable, the more likely you are to achieve a sonic nirvana.

And you may or may not remember that after some rumblings and an e-mail from Jon Wenger, I built "The Finest Digital Transfer Wire In-the-WORLD!" by taking two blue painted wire hangers and cutting an old, cheap, ugly green rca patch cord in two, soldering the ends onto the wire hangers.

You may remember my initial listening tests between that, a cheap, ugly yellow patch cord, a proper RG-6, 75 ohm cable with gold rca's, and the optical tos-link for comparison, yielded no discernable results, BUT there were too many other factors, like my ears may not be as golden or magical as someone else's, or that the toslink was shoddy anyway, etc.

Well, with Jon's help, I have now finished lab testing the cable.

For the dvd player, we used a professional version of the Sony 7000 reference player. It's actually model number DVP-S7000TP, serial # 2023. This is a pretty cool player... it has a nice gray matte, professional looking face, with a really cool rotary region selection switch near the headphone jack! For the processor we used a Dolby Labs model number DP562 multichannel ac-3 decoder, serial # 500280. The very cool feature, which is very necessary for our scientific experiment (since my pedestrian ears can't be trusted to be refined enough for the audiophiles whose heads travel in extra rarified air,) of this Dolby produced decoder is that it will do a bit error rate count... Yup, it will count each and every error it sees... Which is crc (cyclic redundancy check) protected which means the odds of having multiple errors such that the crc check passes an error in the data stream, is almost impossible. The output of the dvd player is an rca coax connector, and the input to the decoder is an XLR balanced connector. Jon normally has a Canare XLR to rca wire connecting the two.

I brought all my wires in case the number of errors that the wire hanger wire rolled was so great, that we would want to try the others and tabulate results... If you would like to see a picture of the wires (including the Sky-Blue/Lime-Green model of "The Finest Digital Transfer Wire In-the-WORLD!") go to: See a photo of the wire on my main Home Theater page.


Now we initially had a little problem with the hookup because we planned on using an rca female to female adapter and putting the test wire right between the Sony 7000 and the Canare cable, BUT we could not find the female to female... Not wanting to give up without giving it the old college try, Jon found two wires with alligator clips on them, so we used those.

So just to recap this thing to death, we had: The professional Sony S7000TP reference dvd player, going to a 20 year old, ugly green, rca patch cord which was cut in two. On one side of the green rca I soldered a blue painted wire hanger to the shield and another to the center conductor. I soldered the other ends of the wire hangers to the other half of the ugly green rca patch cord. We then clipped the alligator clips with thin wire to the centers and shields of the rca connectors of my cable and of the Canare cable, and then plugged the other XLR-balanced side of the Canare into the Dolby Labs decoder. I honestly did not know how badly we would be rolling errors on this one... and with open, scientific minds, we played a dvd...

Are you all sitting down? Good. We played the King Crimson Deja VROOM dvd for over fifteen minutes with this configuration and not only did it sound good, but the Dolby Decoder reported ZERO errors... Did you all get that ok? ZERO, nadda, nihil, zippo, nothing, none... error-free. Given that, there was not much point in trying the higher quality cables I had brought with me.

Conclusion: IT DOES NOT MATTER WHAT YOU USE FOR YOUR DIGITAL CABLE CONNECTION BETWEEN YOUR DVD PLAYER AND YOUR PROCESSOR... YOU CAN BASICALLY USE ANYTHING THAT LOOKS ELECTRICALLY LIKE METAL. IT WILL WORK JUST FINE. (Between the coax connectors that is... I have not successfully used the wire hangers on the tos-link optical connectors... yet...) If you like you can hook the shield on one side to one of your Rodan bronze statues, and the other shield to somewhere else on the statue, and then hook the center conductors to another Rodan bronze, and it will work JUST FINE. The sonic clarity will be stunning, as well as visually pleasing.

So you can use the rca cables they throw in for free into your component boxes that you've been meaning to throw away for months because they offend your sensibilities, or you can spend hundreds of thousands of dollars on Rodan Bronzes and use those, or anything in between... but please do not tell me that it sounds "warmer, cleaner, more open" or anything like that BECAUSE of the WIRE... It may sound different to you or to others... There are lots of reasons why it MAY sound different, not ALL of which are in your head... If it in fact IS different, then this difference is NOT due to the $800 wire you just swapped in. It may be that your player or decoder are somehow defective, or not designed very robustly (i.e. - if there is a difference that is NOT your imagination, then something is broken and you should not be wondering about the wire... you need to look elsewhere for the answer...)

Lastly, if you remember, my original preliminary offer was to sell this cable - "The Finest Digital Transfer Wire In-the-WORLD!" to whomever wanted one, for a check or money order for $750.00 and two soiled shirts and I would send you the cable, in your choice of designer sky blue with lime green ends, or designer bone shell white with banana yellow ends, and your shirts laundered... However, in light of the new lab-tested/hand-made nature of the cable, I am going to have to bump up the price. Yes, you guys had your chance, I am going to have to raise the price to $1249.00 and two soiled shirts. Keep in mind that this is for an error-free, lab-tested on official Dolby lab's equipment, cable. (Don't worry Jon, I'll split the profits with you for an occasional, over the weekend testing session!)

I've pretty much completed this experiment to my satisfaction, and believe I have beaten the proverbial dead horse to a bloody pulp... If someone thinks I may have overlooked something however, my mind is not closed on this topic, and I would be happy to address any serious scientific hypothesis regarding this or other results... Thanks for paying attention... It's been real... Remember, do have fun with your hobby... you are doing this for fun aren't you?

Last edited by Pistol Pete; 02-03-05 at 04:38 PM.
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Old 02-03-05, 05:00 PM
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hahaha nice on the coat hanger

on the component cables, I use regular RCA cables (yellow/red/white), have had, for several years, to my Mitsu 55" 16x9... works just a good as my bro-inlaw's $100 gas-filled monster cables to my eyes
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Old 02-04-05, 01:56 PM
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Originally Posted by dhasegaw
I don't know about "work(ing) just as well" but they'll work. Same with component cables. Shielding and what types of metals and how they are braided and twisted and stuff does affect the quality, so it really depends on what your looking for and in what price range. I'm not coughing up a hundreds of dollars for a few feet of silver cable.
Zero errors is zero errors. No cable can do any better than that. So anything reasonable will work. (Even the cheap thin rca cables that come with many components.) Shielding and twisting and whatnot apparently do NOT (and shouldn't) affect the reliability of carrying DIGITAL signal streams.

Coat hangers and old ratty patchcords and thin wires with alligator clips in series produce no oerrors. I can't imagine any cruddy-but-complete rca patchcord being worse.
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Old 02-04-05, 03:26 PM
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Originally Posted by drmoze
Zero errors is zero errors. No cable can do any better than that. So anything reasonable will work. (Even the cheap thin rca cables that come with many components.) Shielding and twisting and whatnot apparently do NOT (and shouldn't) affect the reliability of carrying DIGITAL signal streams.
The only thing I don't like about the super cheap cables is that they tend to break. I've broken quite a few over the years until I discovered that quality cables can be bought for cheap.
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Old 02-04-05, 04:00 PM
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It's true that, in a digital arena, any conductor will pretty much do. However, the connectors need to be of a certain quality. If you rely on the pack-ins, you may suffer intermittent problems after a few months or less due to corrosion. Try an inexpensive gold plated set and you should be good to go.

Analog signals (S-video, component/composite video, stereo outs from your old CD player/tapedeck/VCR), however, do require a more diligent attempt at shielding and impedance conformity to insure adequate transfer. In the end, let your own eyes and ears be the judge.
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Old 02-04-05, 04:40 PM
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What about subwoofer cables? I don't notice differences between my cheap and higher quality component cables, but my subwoofer has a low hum. I'm using a cheap RCA cable for that. When I ground the cable by touching it, it goes quiet. Does that indicate that it really needs a better shielded cable specifically for this application?

-AC

Last edited by acostigan; 02-04-05 at 04:42 PM.
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Old 02-04-05, 05:13 PM
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Subwoofer cables do need good shielding (as do other analog signal-carrying cables). Also, I believe they are susceptible to interference from power cords carrying 60hz electricity. Try to keep your SW cable far away from any power cords to be safe. But also use a cable with good shielding.

Agree with the above on using good connectors too. These days, even many inexpensive cables have gold-plated connectors, which is all you need.
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Old 02-04-05, 05:31 PM
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No More Wire Hangers!!!

I got into a brief argument with an Ultimate electronics salesperson recently, who tried to sell me a $100 cable for a DVD player. Thin gauge aluminum and copper wire is sufficient *inside* the player, right next to a host of other electromagnetic activity, but as soon as the signal leaves the player you magically need 4 gauge ultra shielded mega Omni cable with Kung Fu Grip?

I don't think so.

How the hell do audiophiles think the signal gets from the disk to the coaxial outputs? Quantum tunnelling?
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Old 02-04-05, 11:13 PM
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agre on subwoofer cable being finicky.. I use cat-5 to extend my sub to the other side of the room, running through the ceiling... I have it too close to the lighting power wire up top, my sub comes out of power-saver mode ("click" turns on) whenever I turn the lights or that room on
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