I've been using shielded audio/video cable with standard rca jacks ($5 at RS) for connecting the bitstream audio from my DVD player to my dolby digital receiver.
A friend of mine just told me I should be using "digital coax" cable.
What is the special about this cable, that I should use it?
If it is something I should use, who makes it and where can I get some?

Thanks!

The special thing is that it costs more.

The signal is digital, as long as you provide a path that allows the signal to reach its destination and that destination can accuratly detect 1's and 0's; you could use a coat hanger...

I use a video RCA cable.

------------------
Steve

There's nothing wrong with a nice quality cable, but Monster Cable for one should be sued for false advertising - they would have you believe that their glorified coax is some special technology. I had a guy at Circuit City telling me that the Monster digital cable was the only kind that would work for a digital connection. What a lie.

I've got the RS gold shielded RS ones too. I've owned a Monster Digital Coax and there is no difference soundwise - like vlad mentions the signal is either on or off. You can show your friend that your receiver is recognizing a digital signal, it should be showing DD mode when it plays a DD movie.

That's kind of what I figured.
Thanks for re-assuring me!
I think my friend probably got told something like that by a salesman in a store as well, but he believed him, because he spent about $100 on various monster cables to connect his system.

Thanks for the help!

Vlad and wolfchild....what kit (amp - speakers) do you use?

Here is what I have:

Toshiba 2109 DVD player
Onkyo 575 DD/DTS receiver
Infinity RS4 fronts
Infinity CC1 center channel
Infinity RS2 rears
Infinity BU-120 sub

Why do you ask though Alan UK? I just wonder as although mine is low-medium end decent equipment, the quality of components has no bearing on this particular aspect of HT.

The digital signal is binary, 1s and 0s and there should be no interference. Think about it, if you downloaded a jpeg or mp3 off the net with a supercomputer and a T3 connection it would be the same jpeg or mp3 as if you downloaded it with a 486SX across old country telephone lines at 9600 bps. The same principle applies to the digital output of a DVD player.

Don't know if that's what you were getting add but I thought I'd mention that.

I have:
Pioneer VSX-906S receiver
Pioneer DVL-700 LD/DVD player
Sunfire Cinema Grand
NHT VT-2 for left and right
NHT VS-2a, for center and surrounds
NHT SW3P sub
www.members.home.net/stevehayden/


[This message has been edited by vlad (edited March 13, 2000).]

I was interested because I wanted to know if the kit you had would show the difference between cables.

My kit comprises:

Pioneer DV-717
Yamaha DSPA1
Jamo 200 centre
KEF Q65 mains
KEF Coda 7 SE rears
Rel Q100E sub

I don't really know how that compares to your kit and I don't even know whether mine is high end or medium or what. I just buy what I can afford. I have been into this stuff for about 10 years now and have found better cables have made a difference to my kit. Tinkles become tinklier and bass becomes more controlled and detailed.

Wolfchild - your arguemnet makes sense and I've got to say that I held the same view when I first went digital...0s and 1s right...they get there or they don't. But I know what I hear.

I was quite happy with my kit until a friend brought a QED cable he had just bought around to my house. I had decent sheilded 75ohm cable linking the DVD to the amp. I was skeptical that I would hear any difference, but hear it I did...not a massive difference, but enough to make me want to spend my hard earned cash on the same cable.

Don't try to tell me I deluded myself into hearing it, cause I don't want to spend money on something I don't need. I could buy a few DVDs instead.

I also have a supposedly sheilded 75ohm cable and that makes the sound very muted and muffled. What's that about?

I dunno...I hear this kind of arguement going on all the time on here and I usually don't post because I don't really understand this stuff...I only know what I hear...and that's it.
Alan

Well that is interesting. I myself could not tell any difference. I didn't really give it a good A/B test though. I used a Monster Cable until I found that I could use the RS shielded coax, returned the Monster and started using the RS and didn't notice any difference.

If anyone else has thoughts on this subject I'd be interested to hear it. I might look this up on some other forums as well. To me it doesn't seem like there should be any degradation of the signal as long as you're using a decent shielded coax. But I'm not going to dispute your results Alan UK especially seeing as how you say you weren't looking for ways to spend more money. Could you elaborate on the difference?

This also brings to mind satellite receivers. I recently purchased a $15 optical cable for my sat receiver from Best Buy. The sales boy tried to get me to buy a $45 Monster version, he said it was five times better! I asked him something like, "So the digital signal can travel thousands of miles, be as crystal clear in both sound and picture as you can get in anything but an extremely disruptive electrical storm" (my dish was almost completely covered in snow last Saturday and played fine BTW) "but the audio signal is going to get all screwed up in three feet by a 'lesser' optical cable??"

Like I said Alan, I'm not meaning to argue with you. If you DID hear some kind of difference I am curious about it. I would ask if you thought your original coax was perhaps defective in the RCA plugs or something, but my argument negates that being a possibility I guess http://talk.dvdtalk.com/ubb/smile.gif

Patch cords make a huge difference in the sound. Many people are simply not interested
in hearing the difference. Test for non believers. Attach a decent cable ie Monster
on 1 channel and the cheapy on the other. The
balance will usually move to the high end side and the sound from that side will have
deeper richer bass and cleaner highs. Speaker
wires have the same effect.

Obviously there isn't a huge difference, as many many people dont hear one when comparing audio cables. If there was a huge difference, most people would hear it, whether they were interested in hearing a difference or not.

And the only fair way to test "differences" between cables is to do a blind test, where you have a 2nd party switch between cables as you compare different sound samples, but you dont know what cables are being used. And I've read several reports on various forums by people that conducted blind tests, and in every case, nobody, not even the "golden eared" audiophiles, could hear a difference.

[This message has been edited by bdshort (edited March 13, 2000).]

bdshort

That agrees with most of what I have seen and heard! The only folks that really dig the high end cables are the salesman!!
$$$$$$$ cha-ching

Even in the blind tests the human 'ear mind' connections can play tricks on you and make you perceive a difference even though there isn't one.

Like I always say, if it sounds good to YOU and you have to live with the budget and the equipment, BUY IT!! Every one's tastes in sound quality is different.....

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by SS:
Patch cords make a huge difference in the sound. Many people are simply not interested
in hearing the difference.<HR></BLOCKQUOTE>

You kind of make me want to beat my head against the wall here. I will agree that better patch cords can make a difference although how much is debatable - probably depends on your equipment.

But in this thread we are talking about
DIGITAL DIGITAL DIGITAL!!! Not speaker wire, or analog coax. This is not an analog audio signal! It is a compressed stream of 1s and 0s that is decoded by your receiver. DECODED. Your receiver should get the signal or it shouldn't. Anything else should be a corrupt signal. Do corrupt computer files work? No. A corrupt bitstream signal probably wouldn't work either.

Now with what Alan UK says, I can at least believe that he does hear some kind of difference although I'm still skeptical. But sitting there saying there should be a huge difference using Monster vs a RS cable for the digital connection sounds preposterous to me.

I guess everyone that works at Monster needs to make money too, glad they have some takers.





[This message has been edited by Wolfchild (edited March 14, 2000).]

Heard this somewhere.. and thought it was great..

"You could probably use a coat hanger for your Digital connection so long as you could get it bent Just Right."

http://talk.dvdtalk.com/ubb/smile.gif

TH

Whoever originally posted the coat hanger line, I read the same review. The bottom line is connect the two digital ports somehow and you will have sound.

Wolfchild, I can hear the difference in the top and bottom ends of the sound range mainly. Tinkles become tinklier and bass sounds more controlled and less boomy. But it is more than that.

Some of the movies I have used have a distinct 'edginess' or harshness when turned up. eg. The Matrix when the minigun bullets smash the windows and tear through the water. Armaggedon: during the first meteor shower, especially the guys falling past with the top of the Crysler building and the top crashing to the street.

Before the cable was installed, I aways had to be ready with the volume control to reduce the volume during these scenes. But now I can not only sit back and not bother anymore, I can also raise the volume slightly above what I used to set it at. The cable has had a smoothing effect to the sound.

Would I be wrong in suggesting that in a cheaper cable not all the 1s and 0s get through and the processor has the ability to guess what should have been there and puts it in? This is error correction isn't it? Does a DD processor do this? I'm guessing here.

At times like these, when people come on and claim I am talking out of my butt (I know no one has actually said that but it amounts to as much), I begin to doubt myself and I check that I am not deluding myself, I checked but I still think I can hear the difference.

I am going to sort out a blind test and then I can settle this in my own mind. I will report back...probably at the week end with the results.

Get the straight jacket ready. http://talk.dvdtalk.com/ubb/smile.gif
Alan

I read a website somewhere (I believe I have the page bookmarked on my computer at school, but I'm not at school right now so I can't check), but someone actually used a coathanger wire to connect his DVD player to his receiver. Both were fairly high end components, and the receiver had a feature where it would display the number of errors in the bitstream. Using the coathanger wire, there were NO errors... I'll say that one more time... NO errors...

I dont believe receivers will "guess" if there happen to be missing parts of the signal. DVD audio is compressed... when you receiver a corrupted .zip file from someone, it is useless... I'd assume DVD audio is the same way.

I'm interested in hearing the results of your listening test, but I dont believe that your audio cable has any affect on the sound... there are plently of other factors that can change sound such as speaker arrangement, slightly different volume levels, etc.

Alan UK, does it sound like bdshort is telling you that you can't hear a difference
in cables. Believe me, you can! He is not interested in the difference and that is ok.
Wolfchild was telling us the difference by
comparing a T3 connection with ordinary
phone line. The speed means everything. I
agree that eventually the main infomration
will arrive to provide adequate sound. It
can pick up stray signal and be slowed by
leakage in the cable. This does not mean it
will not play notes. It will lack sound staging, fullness, openness. And yes, it takes higher end equipment to realize the effect. If all the infomation does not arrive at the same time the sound will be
degraded somewhat. Granted, the dvd digital
converter plays the information when it arrives finally but it may not be perfect.
Please do nut insult us "Tweaks" becaue we
strive for a better sound. We do not insult
you for not. If I sounded like I was insulting I appologize.

SS your observations about 'fullness' and 'openess' are the kind of words I would use to describe the difference I hear with the different cables.

Bdshort....don't cast doubts on my test before I've even done it! I won't be changing the levels or the speaker arrangments. If all you nay sayers are correct I will not be able to detect the difference. I am hoping that I will be able to correctly identify the cable being used http://talk.dvdtalk.com/ubb/smile.gif but if I can't I will tell you and admit that I have wasted my hard earned cash! I have a few cables so I might test it three ways...the new cable against two others...that will be a REAL tester!
Alan

Check out this on DVDfile....another fool I guess?DVDfile Better Cables Review
Alan



[This message has been edited by Alan UK (edited March 15, 2000).]

Thanks for all the great responses.
I had no idea it would spark this much interest.
AlanUK - What brand / part # is your cable?
One of the reasons I originally asked the question was because I am finding myself tweaking the volume knob constantly here. I don't have to do that with the TOSLink cable coming from my DSS to receiver.
I'd be interested in trying your cable and seeing if I notice a difference.
I thought it shouldn't make a difference, but the difference you are describing, is what I'm looking for, so I'd like to try it.

For what its worth, I'm using:
Denon AVR-3200 receiver
Toshiba 2008 DVD player
E* Dishplayer DSS receiver
Boston speakers (VR30's, VR12, VR500 sub and some bookshelf rears)

I don't know if the equipment makes a difference (once again, I don't think it should, all 1's and 0's right).

SS: You mention a T3 vs a modem, and speed making all the difference, but from what I've read, the bandwith in digital audio transmissions is really low anyway. Also, while it might take a lot longer to download an .mp3 file for example (compressed audio like DD or DTS), on a modem vs. a T3, the end result is still the same. The .mp3 wont sound fuller or more open because it was downloaded on a T3. Also, if I sounded rude in my posts, I apoligize... I'm just expressing my honest feelings on the matter here.

Alan UK: I'm looking forward to reading your results. Once I get some higher end equipment (I currently have a Kenwood HTB-502 which sounds really good for $500, but of course I can do better), I will think about conducting my own blind listening test. I dont think I'll hear any difference however.

Another interesting note I thought I'd add illustrating how psychology can definitely play a part in this (which is also why blind testing is the only way to see if you actually hear a difference between cables)... again, this is from a website I dont recall the URL for, but I found them on the Home Theater Forum.
Someone conducted a blind test of speaker wires with some editors of some esoteric high end audio publication. The testers tried something interesting... they TOLD the listening editors that they were hooking up the super expensive cable, and held it up so they could see it... then they played a sample and the editors swore up and down they could hear dramatic differences from whatever cheaper cable was being used... the zinger here is, the testers never actually hooked up the expensive cable... they were still using the cheaper speaker cable.

[This message has been edited by bdshort (edited March 15, 2000).]

SS I too am sorry if I sounded rude - I was tired when I posted that but just wanted to stress that we were talking about digital cable and not analog.

buzzdalf I do have to tweak the volume once in a while during a movie although not constantly by any means - but moreso than with my satellite. But I'm wondering if this is just the nature of the dynamic range of a Dolby Digital soundtrack - some things are really loud and some things are mixed a little too quietly IMO. And with most satellite shows (unless you're watching some DD movies) there is not such a wide dynamic range. This is one reason I like DTS - it seems like most DTS soundtracks I've heard have just been mixed a little bit more intelligently than DD - you don't have to strain to hear dialog as much and other things like explosions aren't as ridiculously loud.

bdshort I can easily believe that a high-quality cable like Monster could have a placebo effect. The Monsters are very nice-looking cables - they FEEL much better than the RS cables, that's for sure. If money was no object I would have just kept the Monster I had - if nothing else you KNOW you have an excellent interconnect whether it's necessary or not. But at the time it was either keep the monster or have the money for four more DVDs http://talk.dvdtalk.com/ubb/smile.gif

I have no hard feelings guys. I do not claim
to know everything-or even anything. I just
felt we were getting a little rambunctous
and I want to be friends. I am having a blast
corresponding though. By the way, I have never experienced that sound drop out and had
to fiddle with the volume. I'm not saying it's cables though.

Bdshort...I was thinking about your .zip file analogy and it doesn't ring true for what we are talking about. My understand of Dolby Digital is that the sound is compressed...yes...but not like a .zip file. I don't think it gets decompressed by the decoder. It is more like a .jpg file. Just like the picture file format, some of the sound has been permanently removed and cannot be put back unless you return to the source material. Ever loaded a .jpg file that is partly corrupted? You can still see the picture but you might find part of it missing or there might be blocks of colour or odd coloured dots that shouldn't be there? I think I am correct...but if there is someone in the know, can you put us right about this.

Buzzdalf...the cable I have is the QED QNECT DS. This is the blurb on the pack:
<UL TYPE=SQUARE>
<LI>True 75 ohm Co-Axal Cable
<LI>Silver Plated 99.999% HPOFC for Improved Conductivity
<LI>Qnect Reference Phono Plug
<LI>Triple-Screened with dual silver plated 99.999% OFC Aluminium Mylar Foil
</UL>

Make of that what you will.

Buzzdalf...if you can audition this cable with out commiting yourself then do...but if you believe the Better Cables review on DVDfile then I would go that way personally.

By the way, I can stick a coat hanger in my TV aerial socket and still get a picture. You might get digital sound this way...but what does it sound like? I once saw a guy on TV cover a piece of sticky tape with iron dust and run it through a reel to reel tape recorder to prove you can record on it. It worked, but it didn't sound very good though. http://talk.dvdtalk.com/ubb/smile.gif

Here is something petty, but it bugs me http://talk.dvdtalk.com/ubb/smile.gif. Everyone on DVDTalk seems to call what they have a receiver. It is only a receiver if it has a radio tuner built in...otherwise it is an amplifier. OK...the lesson endth http://talk.dvdtalk.com/ubb/smile.gif
Alan


[This message has been edited by Alan UK (edited March 16, 2000).]

AlanUK, the DD decoder DECODES the bitstream into 6 discrete channels of audio information that gets sent out to the amp (and preamp outputs, like the LFE). The decompression of each channel has already been done on the encoding/mixing process.

No one has mentioned that jitter is not really a problem with Dolby Digital or dts bitstream because the bitstream gets re-clocked on the decoder side (this doesn't happen with CD PCM audio, thus some people's need for a jitter re-clocker in between the CD digial audio output and the receiver's digital audio input). The decoder either decodes the audio information, or dropouts occur. That is it. There is not extra lost information that gets interpolated by the DD decoder. If the checksum in the error correction scheme doesn't match up, it bit of bytes becomes a dropout and the decoder goes to the next bucket of bits.

A generic 75 Ohm shielded coaxial cable with RCA cable (that is working normally, and has no shorts or open circuits along the cable) should work just as well as the "expensive" cables. These cables are just transmitting low level signal, and truly don't require anything out of the ordinary to function well. These wire are just transmitting voltage levels which are interpreted by the decoder has either a 1 or a 0 by the voltage level it receives once it's been re-clocked.

The "fuller soundstage, the openness, yadda yadda" that you may hear comes from the interaction between the receiver's preamp and amp sections (or if you have separates, your preamp/processor and your amplifier). It's not coming from a better cable that's delivering the DD bitstream from the DVD player to the receiver's (or processor's) Digital audio inputs, because it should either transmit the audio information or it doesn't.

If your talking speaker wire, then it's a new can of worms, and speaker wire does matter for High Fidelity audio. http://talk.dvdtalk.com/ubb/biggrin.gif


------------------
PatCave ;HT Pix ;Pat's DVDs

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Alan UK:
Check out this on DVDfile....another fool I guess?DVDfile Better Cables Review
]<HR></BLOCKQUOTE>

Alan, did you notice though that he could find zero difference between the BetterCable and the $255 one? Too bad he didn't test a $4.99 RS Gold Shielded but he was probably scared to do that http://talk.dvdtalk.com/ubb/smile.gif BTW most of us that say receiver probably do have a receiver; I know my Onkyo 575 has a radio tuner.

Patman, I always enjoy your informative posts on hardware. I was just wondering, and this probably wouldn't apply to really high-end equipment, but INSIDE of a DVD player or receiver, what kind of wires resume the digital connection internally? I mean if you have this nice Monster cable between the units but inside of the DVD player or receiver it just has a small cheap wire, there again I can't see how much good it could do even on analog connections. Just wondering.

Alan UK: maybe an .mp3 file would be a better example then :-) If you get a .mp3 that has been corrupted, it just sounds really screwed up, not less open or what not.
Re the coat hanger, the guy that did this experiment had no errors reported by the DD decoder, and said it sounded fine. And considering there were no errors in the transmission, this would make sense.

Patman: Nice post there... I had a general idea of how DD worked, but your post definitely cleared up a lot of that for me. Thanks. I do think there is some room for debate on how cables carrying analog signals affect the sound, but I think you probably would reach a point of diminishing returns VERY quickly. The people that have speaker wire stands, or wire encased in water filled tubes, and what not are all insane however :-)

Wolfie, for low level signals, normal circuit board traces can carry sufficient electron flow to produce the small signal voltage levels for the audio information, so even with cheap electronics, the electrons are still flowing. Believe me, it's in the power transmission of speaker wires that have more of an effect on your audio enjoyment, and even that is perhaps a 20% gain in enjoyment from good to great systems. The law of diminishing returns works great for high end audio gear.

------------------
PatCave ;HT Pix ;Pat's DVDs

Interesting topic. I changed my optical cable for a digital co-ax cable, and the sound was so improved, I might have upgraded my amp. My girlfiend, who is always sceptical of anything I buy that cannot be worn, readily agreed that the sound was significantly better. 1's and 0's - Bah! Humbug!

Stephen -

(by the way, I enjoyed reading through the previous replies. Very informat - at - tive!)

This debate is raging on some other forums as well. One thing I read was that when you use a Toslink you are using a different interface than with coax and there seems to be a majority that think the coax DOES sound better. Maybe the optical interface in most receivers/dvd players is somewhat inferior? Just wondering....

One other thing, no offense to anyone, but I have better things to do than listen to something fifty frickin times A-B to hear some minor tonal balance between an expensive and a cheap digital connection. This is the kind of testing I'm reading about on the other forums. If it's that hard to tell if you're hearing a difference it sounds like a big waste of time to me. But I guess I'm just not an audiophile to that degree.

http://www.magnani.net/~al/DigitalWireLabTest.html

an intersting read...anyways I was purchasing a new dvd player today and as I was demoing some models the salesman switched interconnects to show me the "difference"...I didn't notice anything different across the spectrum...placebo..placebo...

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Furious:
http://www.magnani.net/~al/DigitalWireLabTest.html

an intersting read...anyways I was purchasing a new dvd player today and as I was demoing some models the salesman switched interconnects to show me the "difference"...I didn't notice anything different across the spectrum...placebo..placebo...<HR></BLOCKQUOTE>

That is the article I was talking about. I think I may go buy some bronze statues once I get back to school, to achieve perfect sound ;-P

Ok...the results are in....

The test was carried out as follows:

A friend and I watched one scene from 5 movies.

Prince of Egypt
Armageddon
SPR (DTS)
Heat
The Matrix

Three cables were tried...one of a £20 pair...a £35 optical cable...and a £50 cable.

We went out while my son swapped the cables and we listened to each without changing anything else.

It was incredibly difficult to hear much difference between any of them. The differences were extreemly subtle to the extent that they weren't worth bothering about. I got the good cable in 3 out of the 5 films while my friend got it right twice. I based my choice on one or two little things I heard which I didn't think I heard with other cables and if I thought the bass sounded better.

I dunno...maybe I could have got it right 3 times out of 5 if I had guessed with out hearing anything... http://talk.dvdtalk.com/ubb/smile.gif What are the odds on that?

What do you guys think?
Alan

Thank you for conducting the blind test.

I think I'm gonna save my money for some dvd's, and stick with the RS cable.

I think that when you go out and buy expensive cables

Your wallet is lighter

So you sit straighter while listening.

Things sound slightly better

lol
http://talk.dvdtalk.com/ubb/smile.gif
Beejay

bump