Home made digital interconnect..

Discussion in 'DIY Discussion' started by Will, Nov 28, 2010.

  1. Will

    Will The Lucky One

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    Any recipes people can recommend? Having experimented with making some speaker cables and analogue interconnects using solid core silver wire and PTFE insulation with good results, I fancy making some digital cables.

    I have acquired some suitable plugs - eichmann bullet RCAs and missing link reference BNC connectors...

    Was thinking solid silver centre core in PTFE insulation, contained within a PVC tube to give some extra rigidity and strength, but am unsure about the shielding or whether a twisted pair configuration works well...

    I have had a go at working with some multi shielded solid core stuff, but its a nightmare to strip and terminate cleanly if you're inexperienced like me!

    Any recommendations?
     
    Will, Nov 28, 2010
    #1
  2. Will

    RobHolt Moderator

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    RobHolt, Nov 28, 2010
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  3. Will

    speedy.steve

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    Yep I have made some from Canare RCA 75 ohm Crimp Plugs and OFC sat sig cable - CT100.
    Make sure it is at least 1.5m long as there is something about reflections with shorter cables.

    Cannot hear any difference when compared to an expensive commercial cable I borrowed or a Belden 1694a with Canare plugs - why would I? :)
     
    speedy.steve, Nov 28, 2010
    #3
  4. Will

    sq225917 Exposer of Foo

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    The much referenced 'refections in spdif' cable was from a piece written by Steve Nugent from Empirical Audio and referred to cables that were not made to spec in terms of impedance and was measured only for a single case, ie one specific pair of receiver chips and a known source and dac combo.

    Basically, you can utterly forget it. Each case is unique with reflections occurring according to the combined impedance of the circuit traces, receiver chips, sockets, plugs, cable length and type used. You would have to measure the reflection time for each case to make the right length cable.
     
    sq225917, Nov 29, 2010
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  5. Will

    Cable Monkey

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    I have to say that the case for using exotic materials diminishes somewhat for a digital cable. I would simply use the best quality connectors I could muster and proper 75 ohm cable.
     
    Cable Monkey, Nov 29, 2010
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  6. Will

    Werner

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    There is no way you end up with the required 75 Ohms characteristic impedance that way.

    I'd recommend the best-possible standard coax for this:

    http://www.maplin.co.uk/Module.aspx?ModuleNo=275&OrderCode=XS17T

    [​IMG]
     
    Werner, Dec 3, 2010
    #6
  7. Will

    felix part-time Horta

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    Will - I've half a reel of Belden 9248; it's a good-quality 75ohm 'RG6' cable. You're welcome to a couple of meters free to play with - drop me an address via PM.
     
    felix, Dec 3, 2010
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  8. Will

    Will The Lucky One

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    Felix...thanks for your offer, you have PM :)
     
    Will, Dec 4, 2010
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