Oh dear, I'm sorry. I was dog tired yesterday and looking back at what I'd written was a little painful. You know you have made a mistake when your writing a piece and the end seems a long way off. I ended up rushing to finish so that I could get to bed.
The coax in your house may be OK. It should be 5 cell polyethylene with a copper foil (not metalised). Yes, it should be 75ohms. Look up coaxial cables at:- Farnell Electronics, RS Spares, Maplin Electronics. All based in the UK but I'm sure you will have similar outlets and products in the Netherlands.
To get the central copper conductor out use mole grips to hold the conductor, I lock the mole grips in a vice then use sand paper around the PVC cover and gently twist and pull the inner conductor out
You remove the outer black PVC cover, carefully remove the braid.
You now have a polyethylene tube with a copper foil covering it's outer surface. I wear cotton gloves when I'm doing this to prevent contamination from the oils and acids on your fingers.
The Impedance of the coax is determined by the distance from core to screen, so if a smaller diameter conductor is used than the one you've taken out, you will slightly alter the ratio of distance and consequentially the Impedance. Of course re-threading a silver 1mm conductor isn't that easy so maybe use something slightly smaller, the difference sonically is negligable.
The braid I mentioned is a new high quality one,as the original braid is useless, thats if you choose to use it. There are lots of options here for providing a better shield and the ERS is probably the best and simplest to Implement. This is a shielding material with military origins. Paul Wakeen @
[email protected] will give you a contact in Germany who distributes in europe. They do a 12mm or so tape and this will do the trick. Please note: It's conductive at the cut edges and when used in any application care is required.
If you use ERS the earth leads are not really essential, but if you don't; yes earth to a component or earth terminal at the source end. This is a rule of thumb, as you could if you wished provide flying leads at both ends and try combinations of earth arrangements.
To optimise the performance of a cable such as this a 75ohm connector should be used. The Eichmann, 75ohm, I don't know. Once again there are many professional termination's available at the above mentioned electrical outlets. You will note that almost all manufacturers of digital i/c's use standard RCA's. A change to BNC would be beneficial if you can modify your player and dac without making a hash of it, though I have never tried to terminate this shotgun arangement to a BNC. It's bound to be awkward.
I also forgot to mention that you will need to cut the body of the rca shell down to (a) provide more room and (b) so you can squeeze the two tubes through far enough to be able to connect and solder without destroying the shield. If you can visualise it, you will realise that it makes for an unstable interface and hence a glue gun and adhesive lined heat shrink are mandatory!
I'm wishing now I had not mentioned this type of configuration as now I'm trying to explain it to you I am realising and remembering how tricky and fiddly it was when I was experimenting years ago. If you have never tried this your going to find it difficult as good quality annealed silver is a bitch at times and I had many failures of solder joints due to poor strain relief. It's to hard to convey to you how to build something like this in just words. You may be as well trying just a single conductor with the copper as return with the vampire connectors. Or a kit. I saw quite a good one at 'The Missing Link' in the UK again. Here you will find the shielded Eichmanns also a good quality silver in his DIY section, adhesive lined semi-ridgid Polyolefin, amongst other bits and pieces. I think that short of getting on the ferry to Holland that's about as much as I can help you, but feel free to ask more questions.
For Google type 'Chord cables' they don't have the digital cable on the site yet but the analogue i/c is there. The digi you can find through the link I provided for you at the bottom of my last post at Audiophile Candy which is full of dubious crud to tempt you to part with your dosh/money.
'Michael Percy' a great resource for the bonkers DIY freak. All the best and good luck.