cable dielectric cause of artificial sound


Hi folks, I would like to know what your opinion is about the following issue. About 90% of high-end cable manufacturers use PTFE as dielectric. Many of their cables sound much alike and they have a few of these characteristics in common: clean, relaxed and laid back sound but at the same time very dynamic (though a bit artificially), very quiet ("black background"), very good (also artificially) left/right separation. But I think albeit these traits, they tend to sound "technicolored", "sterile" and unengaging (lacking PRaT also). Some cable manufacturers are using bleached cotton as dielectric. These cables sound different: they have more natural dynamics, a mellower sound, more intimate soundstage, more tonal colors and so on. Are these differences mainly due to the dielectric material used? Why is for so many manufacturers PTFE still the ultimate dielectric for the use in audio cables?

Chris
dazzdax
How 'bout paper, used about 50 years ago
Why not. It's got a dielectric constant of 2 (dry, at normal room temp). I tried it and it didn't make me run out of the room. OTOH, I can't recommend except for very careful and foolproof implementation otherwise one runs the danger of wires shorting...
JD wrote: "I assure you the interconnects your so happy with will be gone from your system for ever"

If I found something that made the image any bigger than these I don't know what I would do. Like I said I want to try Mapleshades "ribbon in a bag" type interconnect. Thanks again.

ET
There are many valid points being made here, but i think some of the data is being misinterpreted. Obviously, what i posted above was just my point of view. Since we are sharing our points of view, why stop there ? : )

I've mentioned before that many manufacturers cling to one type of geometry for their entire product line i.e. their interconnects, speaker cables, power cords, etc... all use the same basic or extremely similar geometry and philosophy. That's where most of the problems come from.

Each electrical interphase ( component to component, AC outlet to component, amp to speaker, etc... ) has different electrical characteristics. They therefore require different design criteria for optimum power transfer / minimal signal loss characteristics. Obviously, this requires knowing how to juggle all of the variables involved and making some personal decisions as to what one thinks are the most important aspects of signal conduction.

In some cases, minimal signal loss is NOT what is most desirable, so that can also be designed into the product via juggling conductor geometry, dielectric absorption, etc... Once again, this requires an intimate knowledge of how things work, both alone and in conjuction with other materials, and personal decisions as to what the primary design goals are.

On top of that and / or outside of that, certain cable geometries / dielectric materials contribute to cable rigidity. Increased cable rigidity increases cable microphony i.e. the cables acting as microphones and introducing random distortions into the signal. This microphonic distortion introduces a random low level haze, increasing the noise floor, reducing micro-dynamics, reducing focus, etc...

Bare in mind that these distortions can be generated physically ( cables laying on top of devices that transfer energy into them ) or acoustically ( high spl's vibrating air-suspended cables, etc ).

How cables deal with vibration / microphony is a complex subject that many "audiophile approved" manufacturers have never studied or looked into. Many EE's don't believe that microphony is a problem in anything but an utterly defective cable, but i'm not of that opinion. I've seen and experienced very measurable microphonic differences in what one would normally consider to be "good" cabling.

Outside of OR on top of that, some cable geometries are more / less resistant to RFI / EMI induced interference. This type of interference is typically found to introduce high frequency smearing aka sibilance, hardness or brightness into the system. Depending on the degree of the interference and how susceptable the gear is to RF induced noise, some of the aforementioned problems can be perceived as increased brilliance, increased detail, extended treble response by the uneducated ear.

On the other hand, someone used to listening to this phenomena, and having the RFI / EMI reduced or removed from the system, may think that the system now sounds soft, dull, dark, muted or lacking in treble response. In all actuality, the system is now more linear with a truer response, it is their perception that is distorted.

Outside of OR on top of that, there's always the impedance related issues that are involved. Depending on the stability of the gear / circuitry involved, the various aspects of performance i.e. amplitude linearity, frequency response, transient response, distortion characteristics, etc... can be effected.

It should also be noted that any / all of these variations can be random at nature depending on the design of the gear and the impedances that they are presented with. Since the impedance that each cable introduces into the system is placed in series with the impedances of the connecting circuitry, different cables of varying impedances can introduce quite a few variables into the same component based system.

These are but three variables that can alter cable sonics. As previously mentioned, unless ALL of the variables are controlled in phenomenally tight fashion, the differences in cabling / system interaction are typically the result of multiple varaibles, not just one.

This is a PHENOMENALLY complex subject, that obviously can't be resolved in a thread like this. As far as i can see, we need to keep learning and sharing if we are to make any progress in this specific area. Sean
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Sean,

Excellent post, but I think you need to be very carefull when addressing the EMI/RFI issue. Some cables that reduce EMI/RFI issues also dull the musical signal. I think it's important to focus on clarity and dynamics when listening for EMI/RFI problems, not just tonality, because there are already too many people who falsely believe (IMO) that because a cable has reduced the treble response in their system, that it has 'only' removed EMI/RFI grunge, and that their sound is now more accurate; when in fact they have indeed given up some musical information.
A useful learning tool is to apply ferrites to analog interconnects to see how much of a change they make in the sound of a system. Once the listener can quantify that level of change in their mind, it makes determining whether other cable designs are actually better at shielding/rejecting RFI, or are just rolled-off.
(I Should state at this point that I AM NOT endorsing the use of ferrites on analog interconnects).
EMI is trickier, in that so many products use materials that reduce EMI to the detriment of their sound. By placing shielding/insulating materials too close to the signal carrying components, they interfere with the EM field, which impacts the resulting sonics of the system. It seems like some manufacturers would like their potential customers to believe that if a little EMI shielding is good, a ton of it must be great, when nothing could be further from the truth in my experience.

You're right, I feel like I could go on ad nauseum, and still not completely describe my ideas on this subject.
But I guess that's why I love this hobby so much, there's always something more to think about.
I've always said that shielded cables will perform & sound better, when properly implimented. I just don't know of any commercially made cables that are properly shielded, mostly for the reasons you site above. Sean
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