I have here custom made balanced cables. They are solid silver OCC conductors in FEP air tubes. What I do not understand is they have no shielding. I was told that by their very nature, balanced cables do not require shielding and many prefer them this way. Is this actually true? I thought all cables need shielding these are about 3MM in diameter. Thank you
Never mind. I come to find that PS Audio’s own reference system uses unshielded XLR cables. I think that answers my question!
Me, I kinda prefer my xlr cables to have shielding, since the two signal conductors can never be in exactly the same place, so cm interference can never be completely cancelled, but having no shielding will reduce significantly the capacitance to ground which is usually a good thing so it may be worth the trade off especially if not deployed in very electrically noisy environments.
This is why we have Galen
I forgot to mention it has some sort of “magnets”. they are not RFI filters but much larger. I guess that is the “shielding” in their mind? They are directional. apparently these were once good cables. Maybe still are. Not sure. I like the way they sound. I managed to find similar cables this thin that cost a fortune. So i guess they are “serious” after all. I suppose if i like the way they sound is all that matters.
Agreed, listen first. Magnetty type things sounds a bit more “snake oil” to me*, but ignoring that, they can still be good cables.
*unless they are ferrite rings, that would increase inductance, but as RonP says, Galen’s the one for (extremly) detailed cable analysis.
Me, I make my own cables with stock cable from Studiospares in the UK, and generally Neutrik connectors, because the price is low and I have always made my own cables from back in my recording studio days, but that is a personal preference, and my hands are not as steady as they used to be.
I am just putting this for reference. I am not starting my “Schtick” again. They look similar to these. I kind of doubt they even cost anywhere near this. I do not even remember where i obtained them. If they cost anywhere near this I would remember!
Either overpriced tubes of ferrite, or snake oil, but still, the actual conductors are probably fine
Here is an example of such a box taken apart, an MIT cable: clicky.
Thanks @Elk - I expect someone somewhere with the audiophile “golden ears” might here a difference with that, though I would challenge them to be able to identify A/B/X when it is in or shorted, given that the entire thing is shorted by the other conductor pair (if I’ve understood correctly).
Still looks like snake oil to me, and certainly not worth the pots of cash probably paid for it.
In my (I suppose not-so) humble) opinion
I suspect many would hear a difference as the box is adding a low pass filter; i.e., it is a tone control.
A difference probably, an improvement? Goes against the no tone control theory.
Well, yes, but the cable with the inductor in series is bypassed completely by the parallel conductor (with a different Gauge), or have I misunderstood the article?
Either way I’ll be sticking to my heavy gauge multi-stranded copper cables for now
I’m not knocking the more exotic cables, if folks hear a difference/improvement, then it’s worth their investment for sure
I may have misread as well.
Looking back, you are correct. Weird. I still suspect it changes the frequency response of the cable, based on my zero years of electrical engineering training.
No, they claim the “sheath” is not torn in any way. no inductors. Just run through a huge Gauss magnet. their feeling on what it does, too long to explain to me. i feel it sounds very good. Perhaps mine is an expensive cable i have no idea. when i told the guy i had no idea what it cost he was unwilling to tell me. I Called the same place. It may in fact be that cable for all I know. How i got it in a “junk drawer” is beyond me then. This is not another story. I honestly don’t know what it is. it could be a $20 cable. I think it sounds good. I kind of called the other company just to get info. he knew that and it upset him. If it is that cable I have no clue. I kind of doubt it. Anyways I guess these kind of cables are good after all. That is all I wanted to know. The huge magnet is the EMI/RFI jacket but XLR does not require one anyhow. I learned something. Thank you folks.
If it sounds/feels good, do it!
Indeed. I am not really sure what it is/where it came from. It could be the expensive cable/probably is not. I like how it sounds. So that is all she wrote.
Spot on! Very good answer.
Some better designs can mitigate capacitance issues with dielectric and geometric solutions and have BOTH a shield and good CMRR. In balanced cables, the two wires, or more, can’t ever be exactly the same electrical “circuit”, and thus they will have some common mode noise generated internal verses a pure 100% dfferential and ideal signal. A shield won’t stop this “unbalance” called CUB, Capacitance UnBalance.
What a shield does is attenuates EXTERNAL ingress from being higher amplitude common mode noise by the shields dB attenuation rating. A 95% braid shield is 85%-90% attenuation at RF, where copper shields actually shield.
The shield effectiveness is ADDED to the balanced cables CMRR at RF which is approx 60 dB or so, and mostly lower due to the CUB mentioned earlier. 60 dB is still pretty darn good though at low frequency rejection where we have no defenses with the RF only outer braid!
So the two noise mitigaions, CMRR and RF arrenuation work together to cover DC (CMRR only) to RF (CMRR and RF attenuation both). Something an RCA can’t due. RCA shields BLOCK RF only and simply mitigate low frequency issues with the shields DCR as the noise at low frequencies diffusion couples through the shield’s cross section. The noise current times the shields DCR is the voltage induced onto the signal. For RCA we need low DCR shields.
Go low, like 60 Hz, and we can’t stop those frequencies as they pass through copper shields. Same as a magnet through paper. We now have all B-field verse all E-field energy at the exremes There is a cross-over low frequency point where braids offer zip shielding so if we have noise we can HEAR, this is when we go to XLR!
ears always the best judge, at least whilst they still work, and when they don’t it doesn’t matter. me i use ear defenders whenever i use the vacuum cleaner, every bit helps
ps - the worst mains interference i ever heard was in a recording studio where, after all other possible methods were exhausted, we had to suspend multi cores from multitrack to desk in just the right place and orientation and the hum disappeared. turned out the floor below had a large compressor motor in the middle…