Are all optical cables created equal?

Discussion in 'Archived Threads 2001-2004' started by jeff lam, Aug 3, 2002.

  1. jeff lam

    jeff lam Screenwriter

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    Do optical cables have differences like analog cables? Will there be any difference in audio quality between an expensive optical cable and a cheap optical cable?
    If so, can you recommend a good optical cable under $50?
     
  2. Chu Gai

    Chu Gai Lead Actor

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    In qualities of materials such as thickness (4 mm...6mm) sure if we define quality such as a more robust sheathing. There are even cables with metal exteriors that address one of Toslink's issues of fragility. Some cables have plastic type ends, others metal or gold plated...no reason to suspect there'd be issues with that insofar as integrity of the signal. Interior wise you're looking at glass vs plastic. Some companies do a better job at polishing the ends which can result in a greater light intensity but I 'think' this is not such a big issue as the device sees only off/on. For very long lengths, and I do mean long, you would tend to go with glass due to lesser signal attenuation however for the lengths you're probably looking at, say 3 meters, this is not an issue.
    Brands that may provide suitable robustness would include stuff from the Shack, AR's, etc. and you should have no problems easily staying under $50. For reasons that escape me, one can spend hundreds.
     
  3. Mike Matheson

    Mike Matheson Second Unit

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    Personally I wouldn't recommend the Radio Shack stuff in this case. Their optical cable has poorly made ends that fall out of equipment far too easily. I'd go with one of the other inexpensive brands.
     
  4. Gerard Martin

    Gerard Martin Second Unit

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    I suggest you look at Acoustic Research
    good cable, good price, you should be able to get a 6ft optical for about $25.00
     
  5. Neil Joseph

    Neil Joseph Lead Actor

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    There is no audible difference between optical cables as this is purely a digital bitstream carrier. Either the signal is there or it is not.
     
  6. John Royster

    John Royster Screenwriter

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  7. Jason Spencer

    Jason Spencer Stunt Coordinator

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    I bought a cheap (approx $10 shipped) cable from ebay. I haven't noticed any audio dropouts or signal problems. I think its 3 ft (could be 6) long. Sound is very clear and powerful. If it makes a difference, I don't notice it. Perhaps if I did an A/B with an expensive cable or something...But for the casual HT buff, this cable works fine.
     
  8. Dave E H

    Dave E H Supporting Actor

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    I get my from www.partsexpress.com The Dayton cables are cheap and have OK connectors. They sell cheaper cables - really thin - that I've also bought but don't like the cables as much and are more fragile. I think it's less than 8 bucks for a 1 m cable. Good enough for me.
     
  9. FredS

    FredS Extra

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    Although I have no idea if they are right, there are many people who believe that there are indeed audible difference in digital cables. Although it is correct that digital audio is just a bunch of 1's and 0's, the trick is to get the timing of the 1's and 0's right. The degree to which this is incorrect is called "jitter." The better cables theoretically will incur less jitter. A better description is at:
    Read here: http://www.digido.com/jitteressay.html
    Like I said, I don't know if they're right. I've just been researching it.
    Another good read is at: http://www.audioasylum.com/audio/twe...ages/1582.html
    you have to page down to the heading, "How can digital interconnect cables from a CD transport to an outboard DAC possibly affect the sound? Isn't digital audio just one's and zero's?"
     
  10. Chu Gai

    Chu Gai Lead Actor

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    so how does one then measure a jitter specification for toslink and wouldn't one think that as the cable gets longer the problem is exascerbated? as i've stated elsewhere, the current AES proposal for use of toslink in professional applications states plastic for under 5 meters, and glass above that.
    like anything out there, there are limits to what is audible in jitter and what is not. kind of like distortion in that your ears can't tell the difference between 0.01% and 0.0001%. what is peculiar though is that the people over at stereophile claim to hear levels of jitter that are about 2 orders of magnitude less than what current studies indicate. they must have quite special ears I'd think.

    i read the digido link and can only say that what we're dealing with is one persons personal anecdotal story to some extent. that he can hear the difference between 1x, 2x, 4x, etc. is quite a spectacular claim i'd say. also none of it brings issues to bear on toslink.
     
  11. Saurav

    Saurav Cinematographer

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    Actually, there was a paper published in an AES preprint, talking about whether the S/PDIF interface had sufficient bandwidth to handle digital PCM audio. I don't remember if S/PDIF relates to coax or optical only, or both. I haven't read the paper since it's $5 per download, but it was interesting to notice it.

     
  12. Mark Shannon

    Mark Shannon Screenwriter

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    I just bought my toslink cable at the local Home Depot... I believe it was 1.5m for about $30...it does pretty good, and it doesn't look cheap...I bought one for my XBOX from futureshop for like $6, and it looked like just a piece of pastic wrapped in rubber, but amazingly, I believe Walmart sells one identical to the $6 one for $30....
     

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