Cables

Come now, if it was a noisy environment I'm pretty sure a shielded cable would sound better than one that isn't but has noise on the line. I think a lot of houses are RF and EM ect.. noisy places these days what with cordless phones, wireless internet, high frequency bits and bobs in TVs.

But by that same argument balanced connections would always sound better again. I don't have any experience to comment on this though.

Are there any theories that say shielding has a negative effect on the sound? If there are, what is their thinking behind it? I'm just curious.

The cables I use are foil and braid shielded so I am probably about to be told they are really bad lol! Oh well…

 

Hi,

Shielding can only eliminate electrostatic (capacitive) noise coupling (which is minimal as the capacitance to anything outside the cable is minimal), not electromagnetic coupled noise (that is almost all of it)....

A shield is like any other technical device, it has uses and applications it has cases where there impact is neutral and others where the impact is negative. Which is which and where depends on many factors.

Ciao T

 

The debate on cables. That is what this thread is about. As you are aware, it hasn't really got off the ground, so perhaps what is needed is an initiation.

Regarding your comment, I disagree.
Static can build up over time so no it's far from minimal. No capacitance may not neccesarily be shielded, consider the case when the shield isn't grounded.

yes, the main purpose of a shield is as the name implies, to shield, against interference ( electromagnetic)

And hum or noise in my opinion is detrimental to sound quality.

Now let's discuss why cables of similar c, r and h values yet different in other ways, ought to make a difference to sound quality.

Let us debate the truth of the matter regarding why cables ought to be burnt in. Explain to me what burning in is.

Cables apparently, are directional, in the sense that they sound different when connected the other way around. If you are an audiophile, explain the reason behind this.

 

Hi,

Forgive me for not noticing. I thought it was about you being obtuse and controversial....

I did not notice you allowing any debate, actually.

Yes, of course you could make the cable so that static is drained and cannot build up...

You not only miss the point, you also show a DEPLORABLE lack of understanding basic elctrics.

First, I was not writing about shielding capacity, but about the fact that any Shield made fron non-magnetic material shields ONLY and SOLELY against capacitive coupling. So it will shield out any capacitive coupling, but what sort of level of capacitive coupling do we have in normal cables in normal envoironments? fractions of picofarad into very low impedance (the output impedance of the source), which translates into a huge attenuation.

Secondly, electromagnetic waves are not readily shielded by non-magentic materials unless the wavelength is small compared to the physical size of the shield, in other words a few millimeters for normal cables.

So, basically the screen in a normal interconnect is ineffective for the audio range, for the medium and short wave, for very high frequency radio, ultra short wave frequency radio, for 2.4GHz range radio waves (that is WiFi wireless networking, Bluetooth) for all intent and purpose.

I agree completely, but shielding a cable with copper will not help with it, most sources for Hum are in fact completely unrelated to capacitively and electromagnetic coupled noise.

I'd be happy to read your explanations.

Truth cannot be debated, it just is.

They are directional (I mean other than those that have quasi-symmetric construction and the screen connected only on one end)? Can you substantiate that cleaim?

Ciao T

 

What are C R and H values?

 

Capacitance, Resistance and Inductance.

 

Hi,

Inductance surely is written as "L" and not as "H"? Henry is the SI Unit for unit of inductance, as is Farad for capacitance and Ohm for resistance, so it should be either RCL if the items are concerned or "omega" (not sure how to do the Ohm symbol in HTML) which I will write as "O", so OFH....

Ciao T

 

There's no cable debate here on this thread......johnny is making statments, and has to date not answered a single request or given any information. A debate requires both parties to pass information.

So for the last time Johnny......

where are your ideas comming from ?
what equipment are you using?
what cables are you currently using?
why wont you answer even the simplest question ?

 

Yes, but i assumed that Johnny (in his infinite knowledge), used H instead of L.

 

Just back from B&Q with a 25m roll of 3 x 0.5 mm twin and earth (for lighting applications). Seven whole quid !

Are you suggesting using all three conductors for a single run or separate +/- and ignoring the earth ? I assume the former. TBH, the Cyrus cable I have at present is 1 or 1.5mm (I think) solid core, so I'll be interested in any differences - might have to get gf to assist with blind testing. She did comment on the bass extension of the 4.5mm multicore but it was pretty night and day and she likes bass

I wont get to do this for a couple of days because I'm out of banana plugs but I'll post my findings.....assuming this thread hasn't erupted into violence by then.

 

Go simple first ...snip out the earth and use the two remaining wires. You can then try combinations of wires a positves and returns. I actually use a silver solid core of my own that was promted by the use of twin and earth many years ago. I find the silver to be faster and more dynamic than the rather rosy round sound of the copper. Hope all works well ! Watch out for the stiffness of the T&E when your laying it out. I had it spring about and knock an ornament off a shelf.....yes yes I know I can be ham fisted.

 

'H' is used in the states for Inductance. Not sure what the SI unit is.

 

Overall, I'm very pleased. It was actually 1mm solid core rather than 0.5mm and it was a pig to work with. Slightly better than the dedicated 1mm solid core cable I was using before (which I seem to recall cost £2.50 / m in 1988 and was a major upgrade from bog standard QED 79). It's still not quite perfect but I suspect that this is in part due to the 16 amp bass cable delivering so much low end that I'm listening at lower volume settings - I may try some 13 amp and see if things are a little more balanced. On the whole, very good though. Plenty of detail, generally smooth and open although a little thin at the very top end (the sampled hihats on the For Carnations s/t CD are a little thin but I discovered a whole new world of space echoed guitar feedback loops under with synths and regular guitar parts).
Thanks for the advice.

 

Hi,

Any technical text from the US I have come across use "H" as unit and "L" as identification for Inductance.

SI stands for International System of Units (SI).

Ciao T

 

you wrote above that : ''the screen in a normal interconnect is ineffective for the audio range, for the medium and short wave, for very high frequency radio, ultra short wave frequency radio, for 2.4GHz range radio waves (that is WiFi wireless networking, Bluetooth) for all intent and purpose.

So why do most manufacturers bother to use (non magnetic) shields on their interconnects ?

YOU substantiate your statement above or retract it.

 

Johnny = boring.

 

Hi,

You still have other questions to aswer yourself, but the point is basic physics. The shield will "screen out" electrostatic (capacitive) coupling. It cannot screen any magnetic fields until the wavelength of the fieldchange becomes small with respect to the cables screens physical dimensions.

Proof is simple, take a piece of screened cable and one of unscreened cable and a bulk ereaser. Connect each cable in a loop between ground and pin of an RCA Plug, screen goes to ground only. Plug into the lineinput of your Amp, turn up the volume (not too much).

Now take the bulk ereaser, turn on and expose both cables to the same magnetic field from the bulk ereaser. In both cases the noise in your speaker will be about the same, as the cables screen does not and cannot screen out the magnetic field.

L8er T

 

I appreciate your response thorsten.

I still dont understand why shields do not screen from rf ? can you please explain the details to me.


As far as ferrites are concerned , they only work for a small range, so how would that help ?

And I also want to know why interconnects sound different when plugged in reverse ?
Why do they have to be burnt in for upto months to start working as intended ?

 

My thought is why don't we make cable shields from magnetic metals?! Would this cause serious inductance issues or something which could make ground voltage vary? I'm just guessing here!

 

Hi,

> I still dont understand why shields do not screen from rf ?

They do screen from capacitive coupling, but not from magnetic coupling. Radiowaves can be fun, resonance effects are usually present in arials and all sorts of other stuff, so a certain part of the radiation is screened, just as capacitive coupling of hum is screened.

My main point was that screening a cable or not does not provide a reliable indication of good engineering nor doees it indicate from hum & noise.

For example you can use unscreened wires at moving coil cartridge levels with no hum whatsoever (we are talking about 0db = 250uV, that is 80db less signal that the output from a CD player BTW), AS LONG as the two conductors are extremely tigtly twisted to reject Hum fields.

Screens in interconnects probably hark back in the days of the old Valve Systems where the output impedance of a preamp could easily amount 100KOhm + and the input impedance of the power amplifier may be over 1 Megaohm, a situation which would make capacitively noise around 60db higher than for a modern system using otherwise identical unscreened cables.


> As far as ferrites are concerned , they only work for a
> small range, so how would that help ?

Again, this depends heavily on the formulation of the ferrite

> And I also want to know why interconnects sound different
> when plugged in reverse ?

They do? You observed this? I mean not cables that have a screen tied only to one side of the cable, but absolutely symmetrical cables?

> Why do they have to be burnt in for upto months to start
> working as intended ?

Do they? You observed this yourself?

It can be demonstrated that conductors change when moved and when current flows. A process called quantum tunneling can help to make layers of impure metal at the crystal boundaries "porous" to electron transfer.

As AC signals travel in a conductor not actually as current flow IN the conductor, but as EM wave surrounding the conductor (see Maxwell et al) a localised disruption of condcutivity (crystal boundary) may cause a disturbance to the wave, it may do so of course only when it coincides with a "peak" in the waveform, meaning it's effects appear random and tend to be averaged out with steady state test signals, but maybe not with music.

I do not know if this effect is audible. I would not claim with any authority that cables show significant burn in, but several physical mechanisms exist that MAY under certain circumstances very well be audible.

May I ask why you must formulate your questions so extremely confrontational? You state conjecture as fact and demand explanations for them. A Secret Policeman may try such tactics on a suspect to rattle him, I think in this forum a more civilised approach of attaining illumination on the various subjects (or not, as such may be) will get you much better responses.

Ciao T