SPDIF cables?

Discussion in 'Recording/Live Sound' started by Mark C, Aug 24, 2008.

  1. Mark C

    Mark C Member

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    Should I just use plain old RCA cables for this, or is there some special cable I should use? Sorry if this has been hashed over a million times already.
     
  2. elambo

    elambo Member

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    It's a good question.

    Technically, the plain old RCA would work, but I would strongly suggest putting down a little money for a decent cable. $25-30 would be right around the entry level IMO. If this is audio that matters to you (ie - if it's how you make a living), I'd spring for something even better.
     
  3. landru64

    landru64 Member

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  4. elambo

    elambo Member

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    I tend to forget about Blue Jeans. Yep, a very good company with very good products at very good prices.

    And the best part -- after being threatened with a lawsuit, they told Monster Cable to go F themselves, and Monster DID.
     
  5. devilrob1979

    devilrob1979 Member

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    It's a digital cable. Any 75ohm cable will work equally as well as another. As long as it transmits ones and zeroes you won't hear a difference. This is something Best Buy doesn't want you to know.
     
  6. elambo

    elambo Member

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    That's the goal of a digital cable. But cheap connectors, poor craftsmanship, line noise - many things can prevent all the ones and zeros from reaching their destination just as they left the source. When you consider the already poor implementation and physical connectors of many consumer devices, a good quality cable becomes even more important. I've drawn that line of acceptability for digital errors at $25-30 for consumers.
     
  7. gixxerrock

    gixxerrock Member

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    If you ever look at a high speed digital signal with an oscilloscope, you would see a noisy analog signal where everything affects everything. Right down to the material used, and even the shape of the connector. Any impedance mismatches in the signal chain will cause reflections and increase the likelihood of bit errors. This becomes very significant if the cable length (divided by speed of light) is on the same order of the bit time. With short cable lengths, this is not an issue with SPDIF data speeds. As long as the signal is not mangled beyond recognition, it will have a good chance of reconstructing it.

    This is just a long-winded way of agreeing with you (as long as it is not a total POS cable), but saying it is more complicated than people think. I agree with Elambo, this seems to be around $25 cable.

    Shawn.
     
  8. devilrob1979

    devilrob1979 Member

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    If I was going for a long run I'd look at something more high quality but I don't see that as an issue with the standard 1-2 meter line. I could be wrong but I've never had an issue.
     
  9. elambo

    elambo Member

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    I for one don't like to make that kind of assumption about any piece of gear (except maybe Weiss, Prism, Accuphase, or some other brands that could rebuild a perfect word from hashy bits).
     
  10. Mark C

    Mark C Member

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    Muchas gracias guys - that helps quite a bit!
     
  11. MichaelK

    MichaelK Member

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    I looked that up after reading this, pretty funny.
     
  12. jammybastard

    jammybastard "I'm losing my edge, but I was there..."

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  13. elambo

    elambo Member

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  14. jammybastard

    jammybastard "I'm losing my edge, but I was there..."

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    "sub-standard"

    Really? How so?
     
  15. devilrob1979

    devilrob1979 Member

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    Any 75 ohm cable will work, not any cable whatsoever.
     
  16. Pietro

    Pietro 2-Voice Guitar Junkie and All-Around Awesome Guy

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    I've been using the cheapest functional cables I could find for SPDIF transfer since the early 90s and have NEVER had ANY problem with the cheapest Radio Shack Cables (as long as they're functional and not broken). Anything expensive for this purpose is snake oil, based on my nearly 2 decades worth of experience with it.
     
  17. gixxerrock

    gixxerrock Member

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    I have used dollar store RCA cables and had it work ok with some combination of equipment, but not others. My proper SPDIF cables have never had a problem.

    The nature of digital is that it will usually work 99.9999%, or not at all. With a marginal transmission system, sometimes this difference can be as subtle as a bend in the cable or an error recovery algorithm in the software reconstructing the bits. When everything is right, digital is extremely robust.

    If it works on your equipment, great. Consider yourself smarter than a Best Buy stereo salesman and save the $25. But I wouldn't make a blanket statement that there is no difference between a $1 and $30 cable. I do however believe an $80 SPDIF cable is pure snake oil.
     
  18. jammybastard

    jammybastard "I'm losing my edge, but I was there..."

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    ????
    Did you read the description?

    "35ft High-quality Coaxial Audio/Video RCA CL2 Rated Cable - RG6/U 75ohm (for S/PDIF, Digital Coax, Subwoofer & Composite Video)"

    Clearly 75ohm.
    What are you seeing that I'm not?
     
  19. elambo

    elambo Member

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    What a few people don't seem to understand is that practically ANY cable will work, in the sense that digital audio will be transmitted and heard at the other end, but what you receive is NOT what you sent. Errors. Often minute enough that they're not immediately noticeable, especially if you don't know what you're listening for. They're in there. Cheap cable and bad connectors will offer your fill or them. This simply doesn't bother some people, and some to the extent that they can find acceptable logic in unjustifiable over-simplicity.
     
  20. elambo

    elambo Member

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    Suggesting absolutes? It works or doesn't?

    That's simply not true. You'll find that digital transmissions run the spectrum between total silence and perfect reproduction, although the levels in the middle are substantially less noticeable. We're talking shades of green in a field of black and white. But to ignore the shades of green isn't wise, assuming audio is your business.
     

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