A quick interconnect question

Hi,

I am reassembling my 5.1 setup and I am plugging my rear surrounds back in. The problem with this is that I am going to need ~8m interconnects to get to the amp at the back of the room.

Buying an interconnect for this job would cost to much (the ones i use for the front go at £135/m).

So my other thought would be to simply make one.

The sleeving and braiding I can get easily. not to sure about the core. Wires.co.uk sell stuff that sounds the part, but they do not quote quality. though £25 for 100m of .6mm teflon/silver coated Cu seems a very good price.

Does anyone know anything better I could use at a less than obscene price?

If I was to use the .6mm how would it be best to use it?
I need two signal leads and one earth (I willnot be earthing through the braid as it is not designed for hifi use...does anyone know where i could get decent braid?)

with 100m that means I could plait 3 cores for each, twist together and the stick on the braid.

Would that be the best method of assembly?

Would i need to individually shield each core (core being the 3 wire plait) as they are teflon coated?

Any further advice you think i would need would be appreciated!

 

To be honest for ease I'd be tempted to go for something like this:

http://www.maplin.co.uk/Module.aspx?ModuleNo=13256&TabID=1&source=12&doy=6m10

I'd probably then terminate it with some metal bodied copper Eichmann bullets from these guys:

http://www.the-missing-link.net/

What you're proposing sounds rather more hassle than it's worth for rear surrounds to me...

 

Hi,
I am not doing it to be practical. I'm doing it for a bit of fun. They are not standard rear surround speakers they are Acoustic Energy 300s run off a Rotel RB-971. Not brilliant but worth the hastle of a proper interconnect.

Did you seriously notice a difference between Eichman and normal RCAs?

I did a test comparing the profesionally terminated (plastic) eichmans to my homebrewed RCAs. I was so impressed with the Eichmans i sent them back and exchanged them for some new speaker wire.

Its nice to see the price of the plugs ahs gone down to a more reasonable price, they were £15 a plug when i got them (which could have been part of my discust)

 

If you did want to go the complicated DIY route you could check out some of the silver wire from the site you mentioned, although getting insulation over an 8m length might be tricky.

 

I am considering going for the old ptfe tape insulation method. this does not need to look pretty as it is going under the floor.

 

What would you reccomend for the gauge of the wire? is (.6mm x 3) enough or should i splash out for the .9mm. Or would i be ok for just single .6mm wires.

 

I have a couple of ICs that have 0.6 or 0.7mm silver conductors (and no tripling up or anything, just one conductor for the signal and one the return). You're looking at longer lengths, but I don't suppose you'd have any problem with using single 0.6mm conductors. They won't be carrying any significant current after all. Actually my speaker cables have conductors that are only something like 0.7mm diameter I think and they're 5m long...

I don't have any experience of making cables up as you're suggesting though, I've always just bought cable of the type I wanted to length and then terminated it.

I'm not into AV at all, it's stereo only for me, but I really do wonder about the importance of cabling for surrounds? Are there any tests you could do by rearanging some kit to get a feel for what difference it might make? Or have you found before it's important? I understand the desire to make something 'good', but this all just sounds like lots of work to me. But then I am a lazy sod!

 

In truth I am much more into stereo as well. I use my pc sound card for decoding DVD, so the sound is generally crap. I always stand by the philosophy, if something is worth doing it is worth doing well.

Why make crapola interconnects when I can have a whole lota fun making fancy ones.

Thaks for the advice

 

Try a low loss coax satellite cable (pref. white) for a quick, cheap good quality option to get you up and running very quickly

You can then take as much time as you want being as exotic as you want

 

I have some crappy shark interconnects I will be using when my amp arrives (hopefully, lent it to a friend) this weekend.

I will be with the hollow hissy shark sound till I get make some fun ones.

I shouldn't complain about who else does an ok 10m interconnect for £8?

 

Another recipe I use: Buy a decent run of low-loss coax cable from a local supplier (think I paid about £4 for 25meteres). Strip out the copper centre, which is easy to do, and thread your silver wire down instead. You can either use the copper shielding as the return, just solder the two ends to the plugs or run another length of wire down one of the 'cells' that surround the centre. Dead simple, and works a treat. If you want decent plugs, check out ebay, theres a few suppliers on there with WBT copies, I prefer these to eichmanns.

 

What sort of lengths of cable have you managed to do this for? Naively that sounds incredibly hard to do for an 8m long cable?

 

2 metres is the longest Ive done. Personally, I would cut the length up into 1m lengths and use a seperate wire for the return instead of the screen. As these cables wont be seem insulation tape could be used to join the lengths once done and use heatshrink tubing over the joints.

 

I must admit that does sound an easier way of doing it....the thought of plaiting 10 m of wires does sound amusing though. One of those projects that sounds easy but 3months later you are stil doing it.

 

Hi,

I'll second the "core from sat coax with silver wire" methode, it makes for stonking good cables.

If that is still too much, consider simple trunk style Cat5 (or higher) network cable. FOr use as Interconnect use a pair of the wires for signal and return and use the remaining three pairs as "screen" equivalent.

The result is not halve-bad, I would certainly not be worried using these for the surrounds for movies or even music in most systems.

Ciao T

 

Forgot to mention that one - I've got a 13m interconnect between my main system and a second system, and it works damn well.

 

...and from my experience, I'm not too sure you really need the 'screen'. A single twisted pair itself does a good job.

 

I would bother with a screen on a cable that long to be honest. Certainly on a 5m cable I had running to my sub the shielding was important, to prevent mains pickup (but then it did have to pass several mains leads). With the freebie lead I had this was significant, so I made a lead from Van Damme Starquad (chosen for it's good screening) and Bullets, which eliminated the problem. I suppose it might be the case that the rear surrounds in question don't output much at 50Hz though?

 

The whole point is that the twisted pair provides an inherent noise rejection mechanism. How effective is down to individual set ups. My 13m interconnect is effectively a 'tape' connector - L-in, R-in, L-out, R-out - with one twisted pair for each signal, and runs alongside mains wires and speaker cables, and I don't seem to have any problems

So, I'm not saying it will work in all circumstances, or that something better couldn't be constructed with twisted pairs. I haven't bothered to compare with anything else. But it's a very simple way to contruct a long and effective interconnect, and it's very low capacitance, so no hi freq roll off even over very long lengths. Then you can spend time experimenting with other interconnects should you be driven to do so.

YMMV

 

Hi,

My recommndation to use the rest as "screen" is based on using Cat5 off the shelf and without using it as multicore. In that case leaving 3 pairs unconnected can be a potential source of trouble, better connect them all at the load end to ground. If used as multicore, then use the needed pairs and keep the remaining pairs grounded on one side.

Ciao T