Shielding on interconnects [Archive] - The Art of Sound Forum

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julesd68

31-03-2013, 14:01

Having got a new rack I need to get a longer interconnect to run from my valve phono stage to hybrid amp.

What exactly do I need in terms of shielding?

Is a copper or aluminium shield adequate or do I need a braided shield aswell?

Firebottle

31-03-2013, 14:19

If it's a full wrapped copper or aluminium foil shield that will outperform a braided shield.
You don't need both, a braided shield gives greater flexibility to the cable.

:cool: Alan

Wakefield Turntables

31-03-2013, 15:29

Cu or Al will work really well, the thicker the better.

YNWaN

31-03-2013, 15:33

Most 'shielded' interconnects either use a Mylar foil or a braided sheath (quite often both). In terms of reducing hum, I have found the braised shield to be, by far, the most effective (it doesn't matter what metal it is made of).

julesd68

31-03-2013, 16:04

brian2957

31-03-2013, 16:09

The shielding in Mark Grants cables is excellent . These cables are difficult to beat at this price IMO . Some other cables which I would also consider are the NVA Soundcords and also SSC ( Super Soundcords ) which are also very good VFM and very well shielded . Lastly, the Rega Couples are also very well built with excellent Neutrik Profi RCA plugs fitted .Shielding is also very good. All IMO of course (:

YNWaN

31-03-2013, 16:16

hmm - options, options again! :scratch:

I note the Mark Grant cable uses a "dual layer shielding system consisting of two layers of dense coverage high purity copper braiding".

Presumably this is the best "belt and braces" approach?

All the cables I mentioned in your recent 'what £50 interconnect' thread offer similar levels of shielding.

julesd68

31-03-2013, 19:42

I'm not a cable swapper, just want to fit and forget, so want to spend a little time making the right decision here.

I've got Cable Talk 3 speaker cable so I thought I'd look at Cable Talk interconnects. The Missing Link bought up all their remaining old stock I believe. They are offering the top of the range Reference 3 for £65 - "4 x 6n pure copper conductors wrapped in a solid 6n pure copper foil tube for a perfect 100% shield". Doesn't really mean much to me - I'm sure it isn't the latest cable "technology" but is this value for money by today's standards?

brian2957

31-03-2013, 20:10

There's a lot to be said for keeping all the cables in your system from the same manufacturer Julian . I've never heard these but I doubt if cable technology has changed so much as to make these obsolete . If the plugs look decent then there shouldn't be any problem with these interconnects at this money. Got a link to these mate ?

julesd68

31-03-2013, 20:42

brian2957

31-03-2013, 21:04

These look like a bit of a bargain Julian . Seem to be very high quality cable for a very good price . Please let us know how you get on if you buy these .

julesd68

31-03-2013, 21:53

Will do Brian.

I would buy them immediately if they were to run between amps for example, but just want to be sure that they are appropriate between phono stage and amp where I believe the signal is most "delicate".

julesd68

31-03-2013, 22:03

Hilarious thread on Wigwam about having all your cables by the same manufacturer ...

http://www.hifiwigwam.com/showthread.php?85097-Single-cable-supplier-solution

YNWaN

31-03-2013, 22:37

The funniest post is from the chap who compares using different makes of cables to using different tyres on each wheel of your car - pure comedy genius :).

Stratmangler

31-03-2013, 22:50

This post is possibly the most accurate ...

Tuck it behind the rack and nobody will ever know. Including you, if someone else did it without you knowing. :)

julesd68

31-03-2013, 23:08

The funniest post is from the chap who compares using different makes of cables to using different tyres on each wheel of your car - pure comedy genius :).

Funny. I had a similar conversation with Honda when changing my tyres last week ... :eyebrows:

Barry

01-04-2013, 01:25

Not just any plugs these Brian! ;)

< The RCA connectors machined from solid billet medical grade non magnetic stainless steel with adjustable cantre pin & skirt with hard gold plating for excellent contact >

Medical grade! If they are good enough for surgeons they're good enough for me! :lol:

Here's the link - you need to scroll right down to the bottom of the page -

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

This is a good example of meaningless advertising "techno-bollocks". Exactly what grade of stainless steel are they using?

http://en.wikipedia.org/wiki/Stainless_steel

If the interconnect has a true coaxial construction, the shield must be one of a proper braided design. If the interconnect is of the so-called "semi-balanced" types, then the shield can be a simple lapped type.

The aluminised mylar with drain wire shields are only useful for RFI, not EMI shielding and are totally unsuitable if the shield is to act as the return for the audio signal.

DSJR

01-04-2013, 11:03

Kevin Edwards (now Talk Electronics/Edwards Audio) , who was then the "brains" behind the designs of the original Cable Talk products, did some fancy things with the gauge and number of conductors, as well as the types and degree of shielding in the wires. The capacitance and inductance varied widely I believe, depending on the model of cable.

If these are still available -

Monitor 3 (and especially the earlier Monitor 2) has a rich, bold sound which was ideal for cheaper, leaner-toned CD players of the period

Broadcast 3 is an odd one here, sounding like a cheaper patch-cord but FAR cleaner. Loved by a Sugden dealer I recall as it suited their amps well. Also Quad amps liked it a lot and an old friend still has one custom made in a "Y" form from his 66 pre into two 606's bi-amped.. made the QED Silver Spiral sound soggy and thick toned I remember.

Reference 3 was a very popular cable and worked a treat with a huge range of gear. We sold loads with Audio Analogue, Arcam, Musical Fidelity X series (until MF pulled the plug on us) and it beat the Chord Chorus at the time for overall fidelity.

There was going to be a Signature interconnect using gold plated conductors, but the twin inners couldn't be separated apparently and it came to nothing. The previous Signature 2 (blue jacket) was a delightful and truly excellent cable I remember.

Sadly, the then new Talk Electronics line bled the company financially dry, the two business partners separated and the electronics firm clawed it's way onward and upwards, sealing a good export deal at the time I recall. The cable line peed off a number of large established dealers through not being able to supply (lack of money to buy the required Km of wire at a time?) and of course Black Rhodium (as they're now called) and Chord Co were waiting in the wings with lots of incentives and plenty of stock for the larger dealer chains to buy and immediately deliver....

YNWaN

01-04-2013, 13:34

I can't think of any RCA plugs that use stainless steel; but then, as Barry says, I can't think of any valid reason why stainless steel should be used for them either.

DSJR

01-04-2013, 14:02

Nice finish?

julesd68

01-04-2013, 23:13

Many thanks for all the info on Cable Talk, Dave, most helpful.

I am wondering what you know about Cambridge Audio cables? :eyebrows:
I'm interested in the older ones - they go for pocket money but I can't find out any specifications about them at all ...

YNWaN

01-04-2013, 23:17

Cambridge Audio - owned by Richer Sounds...

YNWaN

01-04-2013, 23:19

Nice finish?

Or, won't corrode if you swallow one..

julesd68

01-04-2013, 23:25

Cambridge Audio - owned by Richer Sounds...

yeah I know but that doesn't actually put me off in this case - I think there might be a vfm potential here as they will be largely ignored by people because of that, no matter how well made they might be.

YNWaN

01-04-2013, 23:36

I've done a quick search and the only mention of shielding I can see is mention of a mylar screen - which will do very little.

julesd68

01-04-2013, 23:39

I found some old "Pacific" ic's which feature triaxial geometry - I am right in thinking that the shielding on this will be more substantial?

brian2957

02-04-2013, 00:34

Send em up to Glasgow for Saturday Julian and we'll have a look at them for you mate :eyebrows:

YNWaN

02-04-2013, 00:49

I found some old "Pacific" ic's which feature triaxial geometry - I am right in thinking that the shielding on this will be more substantial?

Don't know I'm afraid. The term triaxial doesn't mean anything in terms of shielding and probably just means there are three wires used in some manner.

Firebottle

02-04-2013, 06:01

YNWaN

02-04-2013, 08:54

Oh, never knew that :).

If this cable is made in that manner, then I guess the inner braid is used as the return (not uncommon).

Barry

02-04-2013, 20:19

Triaxial normally means double screened.
An inner wire then a screen, then another screen on top. The two screens are insulated from one another:

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcRTOCpuUOxgVawE3s-6PEG8zaNHBipTT9JOz7RaGGTz_J4KIYmv

:cool:Alan

"Double screened" means there are two woven/braided screens, each in electrical contact with one another along the length of the cable. Since no woven braid can provide 100% 'optical coverage', the use of two braids can help since statistically one will cover the gaps in the other. Double screened cables will have a lower surface transfer impedance and hence better shielding.

Triaxial cables are as you have show. They have two concentric screens that are electrically insulated from each other along the length of the cable. The two screens are often connected together at the cable ends, but not always. This configuration can have screening/shielding advantages at RF. Triaxial cables are often used for the video from TV broadcast cameras.

I have experimented with using triaxial cables in my system and have found, at audio frequencies, they offer no advantage over double screened cables.