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Ever since my dad put together a hifi system--one of the first, back in the late 1940's--I have always taken it for granted that shielded cable must be used for interconnects. That's what he used between the Pilotuner and the David Bogen DB10 amp; and from the record changer to the little RCA preamp; and from the preamp to the Bogen. It didn't even have an insulating jacket. The shield was right on top.
Oh, I knew that you could use a twisted pair--but if your stereo was any good, you wanted shielded cable.
For years, I have made my own interconnects. What's wrong with RG-59 terminated with pretty gold-plated RCAs with fancy coil-spring strain reliefs? Well, I've tried microphone cable too. And not forgetting the Canare cable I eventually swithed to. But now, all this is apparently anathema . . .
In reading, recently, I have gottten the impression that shielded cable is passe. Old fashioned. Sonically inferior. Now, we must have tri-braided cable, or something woven by a zen master--and definitely NOT shielded.
IS there anything to this? I have a pair of half-meter Kimber PBJs. They run from the CD player to the preamp. Good, but I'm not sure I hear the difference between them and my DIY microphone cable interconnects. Or is the Monster cable (shielded) between the preamp and power amp obscuring the subtle superiority of the Kimber?
Is shielding a No-no?
Follow Ups:
Vovox makes their cables in both shielded and unshielded versions. This is what they say about choosing one over the other:
"How does one choose between shielded or non-shielded cables?
Many VOVOX® sound conductors are available in a non-shielded 'direct' version and in a shielded 'protect' version. The shielding prevents humming and buzzing sounds, but causes a small loss of sound quality.
There are situations in which it's mandatory to use shielded cables. On the other hand, especially with balanced cables, there are very few cases in which sound disturbances are observed, even without shielding. 'Direct' sound conductors can offer even better results in these cases.
Generally speaking, we suggest using 'protect' sound conductors for applications in which interference would otherwise cause problems (listed below). In all other cases, the non-shielded 'direct' versions should be favored.
* when interference will necessarily lead to an uncontrollable situation, e.g. for live concerts or live recordings
* in the case of unbalanced cables longer than 1.5 m (5 ft)
* for phono record players
* for amplified music instruments with pick-ups"
I have an unshielded Vovox TRS-XLR mic cable between my computer source and silver Django passive pre. It's the only copper cable in the rig...very happy with it.
and I thought it was just me ......
all cables destroy your music signal ...the best ones are the ones that do the least damage.
The reason why heavy shielding is often used is that mass market cables makers can buy huge drums of the stuff off the shelf..thats often been designed for other purposes imo
shielding added to one pair of identical ic's can clearly be heard to reduce dynamics and muddy up the image ...well in my system !
and to answer one of the other posts .....if you can hear an ic's difference in one position in the system ie between pre and power there seems to me absolutly no reason why it could not be heard elsewhere ..unless there a serious equipment or impedance mismatch.
Howdy
Playing the devil's advocate:
You said "if you can hear an ic's difference in one position in the system ie between pre and power there seems to me absolutly no reason why it could not be heard elsewhere ..unless there a serious equipment or impedance mismatch."
Yet in a digital only system (i.e. ignoring the vinyl cartridge to phono pre connection) the pre to amp path is typically the lowest level signal and hence is more sensitive to any constant background interference, be it a ground loop, EMI, RFI or whatever.
-Ted
About 6 months back I switched from a pair of shielded, garden-hose type IC's to a pair of Kimber Hero's (both pairs are XLR).
The Hero's are a simple twisted or braided design with some techflex protecting the conductors. The air and dynamics of the Hero's far exceed that of the shielded IC's. I tried the shielded one more time after recently switching speakers and had the same result - loss of air and mid/high dynamics. The Hero's are keepers.
Disclaimer: I have yet to hear any difference in IC's between source and preamp; only between preamp and amp (when I had such a set-up).
I have one half-meter pair of Kimber PBJ between CD player and preamp. I just braided up and terminated a 1.5M pair, using #20 hookup wire (red, green, and black--very pretty). Home brew- pseudo-Kimber. Faux Kimber. On one piano concerto, they sounded great! Lots of detail and subtlety; yet the loud passages had a sense of ease and clarity to them.
But on most other recordings, they sound tinny. Too much high-frequency emphasis. I suppose that's where the detail came from. But it gets quickly tiresome, and the balance is wrong. Sounds fine on FM, though. Of course, they are only home-brew, not real Kimber Kable.
I wonder--how similar to that would things be, if I PBJ'ed the whole system with the real thing?
While garden-hose type IC's are dark or veiled on some systems, they can bring out a midrange magic on the right system. I was in search of a more open, airy presentation and found it with the Hero's and the Gershman Avant Garde speakers I recently acquired. The lower midrange might be a wee bit on the lean side, but I attribute that more to the fact that I was listening to speakers with a much richer lower-midrange for the past 6 years.
Having used PBJ in my all SS system at one time, your description of the sound of your home made Kimbers to me is very similiar to the real thing-very detailed but bright.
a modest cable with many of the same virtues but not bright is DH Labs BL 1.
In addition to being more detailed, my tri-braids sound more harmonically coherent than the shielded coax. And orchestral peaks seem cleaner, less distorted, or less muddy (not sure what the best adjective is). They sound great with FM radio music, and I am finding more CD's that sound right with them. I can see why Kimber has so many fans.
Is shielding a No-no?
I don't think so.
I've installed unshielded and shielded cable that has worked, it just depends on the situation and the surrounding environment...
To extract every bit of detail (pun intended) from a well-recorded Redbook CD, you need cables that are both shielded and damped. Shields reduce noise, but can inject their own artifacts if they are not damped against electromagnetic resonance.
I've only recently begun to understand how tricky this is, so I recommend avoiding shielded cables in most cases.
Braiding is also tricky, and can make things muddy if done incorrectly. Simple twisted-pair of good wire will preserve most of the fidelity in most cases.
Yes, the Monster cables may be damaging your signal. If your preamp has sufficient drive, you need shielding even less at its output.
I have not found shielded cables to outperform well constructed unshielded cables. I too find a reduction in dynamics and air with shielded designs...
HowdyPardon my ramble, but bear with me:
I have way too much gain in my system in that I can turn it up about 30dB louder than too loud, however this allows me to hear the noise earlier in my system pretty well if I pause my sources or (carefully) use a track with extremely low levels. When I turn my system to full volume and invite my wife or daughter to listen right at the tweeters I have just a minute amount of white noise so I'm guessing that my unshielded cables are doing great at reducing the noise pickup in my system. (I have in the past had much more colored noise under these circumstances and have explicitly addressed the issues so uncovered.)
Every type of shield I've used (from very small amounts of ESR paper to cables with a little graphite to cables with more, to explicitly shielded cables to coax for speaker wire, etc.) all mess at least with the macro and micro dynamics of the music and with the overall coherence if not also explicitly rolling of the highs loosing air, etc.
Don't get me wrong: I know that there are a lot of systems which are quite sensitive to RFI, EMI, that are microphonic in various places (including their cables) and that almost everyone of your posts is correct when talking about those systems.
However there are also systems that are better designed which are less sensitive to these forms of interference, still are resolving and detailed and yet are very engaging. Hence I think that at times you overgeneralize.
I have no qualms saying my system is one such system because I can hear differences in cables, mechanical isolation, power cords, etc. as well as that I've visited many other people's houses, shows, etc. and can comfortably say that with the exception of one other inmate's system (and then only sometimes) mine has the most resolution I've heard.
This is in part why I've invited you over on the past (tho I know that most people don't have the time or inclination to visit a pig in a poke system :) One reason is that it's always fun to have visitors (and to visit others) and another is that it's always fun to see how other paths lead to systems that are just as enjoyable as our own.
I'm not claiming my system is perfect, far from it. But most of your posts (tho correct for many systems I've encountered) are so far off of the mark for a few systems I've encountered that I have to speak up now and then :)
-Ted
RF noise is not directly audible, even by a teenager :). It affects the audio signal through intermodulation, so it is silent when the signal is zero. A small amount of it adds apparent sparkle and a sense of air, as well as enhanced punch on plucked strings and struck cymbals. However, it obscures the microdynamics that give Ella Fitzgerald, for example, her characteristic vocal texture, or allow the differences between cymbal tones to be savored. Someone (such as me) familiar with a well-tweaked setup incorporates these system behaviors into a notion of the baseline performance. The only way to know they are there is to hear the system with them removed. What I'm trying to get across is that your system may be better than you can possibly imagine.
One component of the RF noise environment is the spectrum of tones produced by resonant objects in the audio system. These objects may be cables and power cords as well as parts of the speaker crossover networks or wiring. One particular type of resonant object comprises the shields on shielded cables and cords. While they may function to reduce audio band noise, they act to increase the RF noise environment by resonating unless measures have been taken to damp them.
This is why many folks with refined systems do not find shielded cables useful. They do not have strong sources of audio band noise, so the only action of the shields is to degrade the signal. I'm not going to go into the details of what it takes to properly damp shields because a lot of the information is proprietary to others.
Unshielded and undamped cables act as transmitting and receiving antennas for RF noise. An audio system using them could achieve complete Redbook resolution if the connected equipment were sufficiently insensitive to the RF noise, including the resonant tones, present on the cables. I don't think any such equipment exists, but the trend in behavior reported in published reviews of ultra-expensive equipment suggests to me that designers are working in that direction.
I appreciate your invitation to hear your system. I don't travel much, but would let you know if circumstances lead me to the Seattle area.
HowdyPerhaps I misunderstood you post.
I saw: "To extract every bit of detail (pun intended) from a well-recorded Redbook CD, you need cables that are both shielded and damped." which seemed pretty unambiguous.
But perhaps you meant it to be read with your subject: "Only for lower-resolution systems to extract every bit of detail (pun intended) from a well-recorded Redbook CD, you need cables that are both shielded and damped."
Anyway, yes, I understand the distinction you are making between RF noise and audio band noise and I also understand a lot of the many ways they interact in practical systems. However I still stand by my statement that there are well designed systems that aren't nearly so twitchy as apparently many posters here are subject too.
In fact one might state: "if you can't hear how a shield deleteriously affects your audio your system isn't very revealing" I know that this isn't really true in general but it's at least as true for many systems I know as my reading of your first post.
-Ted
P.S. Perhaps if I get down your way I visit you, Bart and/or some of your friends.
Most commercial CDs have less than the maximum resolution allowed by the format. A few reveal increasing recorded details with improvements in noise reduction techniques in highly resolving systems. One of these techniques involves how the cable shields are damped. Incorrectly damped shields will harm the signal, and do more proportional harm in highly resolving systems than in more modest systems.
The problem is that these improvements are subtle and easily confounded with the basic tonal balance. As I wrote above, some degree of RF noise pollution sounds like added sparkle, air, and punch. Removing it makes the system sound dull. The additional true detail only becomes apparent after prolonged listening. If the system's tonal balance had been selected based on some amount of RF noise, the system will remain dull with the noise removed. Rebalance may be expensive, as it may require new speakers, etc.
I realize there are pleasing and highly resolving systems that use unshielded cables. My assertion is that they could be even more resolving (and more pleasing, if such resolution is to the taste of the listener) if the cables were properly shielded and damped. Simply adding shields without attention to the damping will not, in my understanding of the issues, guarantee increased satisfaction, and will likely decrease satisfaction. We nearly agree on your comment, "if you can't hear how a shield deleteriously affects your audio your system isn't very revealing," but I would only add 'an undamped' to the word 'shield.'
Let's see: damping involves the introduction of lossiness. In a mechanical system, that would call for a shock absorber. In an electrical system, resistance would be needed. But how to introduce resistance into a shield? Interrupt the shield every few inches and solder a resistor from one section to the next?
Hmm, maybe not. How about a resistor between shield and center conductor every few inches. It would load down the source, though. Okay, resistors between shield ground and chassis ground? With a third wire to carry the chassis ground?
The extracted energy is dissipated and converted to heat.
Ohmic resistance is involved, but not necessarily resistors.
Further details are proprietary to others and not mine to share.
Hmm, mayba a conductive, but lossy, carbon-impregnated shield?
Hey, how about carbon nanotubes? Just a wild guess, but it sounds classy!
Howdy
Some carbon shields may work (I don't know), but some certainly take the dynamics out of the music.
-Ted
.
Removing it makes the system sound dull. The additional true detail only becomes apparent after prolonged listening.
I find that one can hear more detail at lower levels with a well shielded system. You don't have to crank them. Everyone (especially the Hornies) talk about dynamic range, but usually refer to the loud end. Exploring the bottom of the range can be equally satisfying to me.
rw
The details are at the lower end of the dynamic scale. My visual analogy is that improving the lower-end dynamics is like turning up the lights at the back of the stage.
HowdyThat's what I thought you meant. And to beat a dead horse I disagree at least in the context of some systems. In fact I really don't think you can improve my system with any kind of cable shielding... There simply isn't any of the sound of RF artifacts that you describe here or any of your other posts, yet I get amazing amounts of detail without fatigue. I have spent a lot of time making sure that I don't have any fatiguing symptoms since my system is on 24/7 and playing sound probably 20 hours/day on average. (Now that I'm married I don't sleep in front of it anymore, but I used to :)
Don't get me wrong I'm not trying to generalize my experience and say that properly built shielded cables don't exist, but in my experience they appear to be as rare as systems that don't need them are in your experience :)
I tend avoid any changes to my system that mess with the tonal balance, it both sounds right and measures well (at least with a crude 1/3 measurement. Someday I'll either write or borrow a good spectrum analyzer for measuring my room more accurately, but it's fine for now and I have higher priority work to do.)
Perhaps you haven't looked at my profile to see what speakers and other equipment I have as well as you might have missed my room treatments... With amps flat to 200kHz, speakers flat to 40kHz (or is it 50kHz?), and silver speaker wires and interconnects some might think my system would be bright or etched, but far from it. It's appropriately smooth top to bottom.
Believe me I can hear/measure the effects of RF in my room. (Tho my scope only goes to 200MHz I've been measuring things enough to have a pretty good idea what's happening up to there...) In other situations (my older office system or in the store where I bought a lot of my components) I could easily hear when people's cell phones were receiving a message before they plinged, etc. and could tell when people were downloading on the computers in the next office... In my old house I had to move components around to avoid the interference from my old Sony Wega: it had horrible fields about 6" directly under it rendering the top shelf Tivo/video/UPS land, not audio land. Different Tivos are built quite differently, some have horrible ground loop issues and others are clean as a whistle. Some have noisy disk drives, others are quiet. The fans are all over the map.
It used to matter what time of the day I played my system, but that's long behind me, it's clear, clean and engaging any time of day or night. These kinds of fixes (find a problem, measure it, do some research if necessary, design a fix, measure that, iterate) for various problems have left me with confidence that I'm not (in general) chasing my tail and that (also in general) I have a good idea what's going on in my system. I have explicitly not addressed some known issues because I don't like any fix that's avaiable, but these are more like room issues...
I'm rambling so I'll stop. I just had to engage you on this topic at least once :)
-Ted
do not yet exist to my knowledge.
I should have made that clear at the beginning to avoid some misunderstanding.
The ones I know about are still under development, and may never get to the point where the designer is happy with them. What I've heard along the way, though, is what motivated my bald assertion regarding resolution and shielding.
I'm glad you are happy with the performance of your system, but I don't agree that it is entirely free of RF noise artifacts. I have too much experience with confounding the subtle effects of RF noise with system balance.
Howdy
Ah..
Well I'd like your personal assessment here sometime, but I know that's impractical.
Still presuming I'm still subject to some degree of RFI, my experience is clear that any shielding whatsoever has clear effects on the audio band so till I hear with my ears otherwise it's clear to me that shielding throws the baby out with the bathwater: any positive effects (which I doubt in my system) are clearly overwhelmed by the negative effects.
Does your associate need a discreet beta tester? :)
-Ted
:(
Howdy
Most people would look at my system and think it was a prime setup for shielded cables. In my sound room (let alone the rest of the house) I have Tivos, a rack of CD jukeboxes, video jukeboxes, computers, laptops, wireless internet, wireless phones, cell phones, at least 8 of my neighbor's wireless networks are strong enough for me to use should I choose...
Still I get the best sound with unshielded cables. Some might say it's because my hi-def audio path is all fully differential (sources, interconnects, preamp and amps), but even when I was running unbalanced in my old house with similar equipment I still got the most open natural sound with unshielded unbalanced cables.
YMMV :)
-Ted
Every cable I have from power to interconnect and speaker is unshielded and not braided. It gives me the most open sound,largest soundstage and so on. I had mid-high dollar cables that were shielded and braided before. I live in the sticks: no cable, no cell service, no TV or radio tower within 25 miles. I have DSL through the phone line. I use various AC filtering and regeneration. Cable proximity management is more critical using unshielded cables.ET
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