Cables do not matter?
Minimal sound changes ...
Cables should be evaluated for their neutrality and not for their sound changes.
It is absolutely amazing how many high-priced and yet physically completely wrongly designed audio cables are still to be found on the market today.
While there are some complicated physical reasons for the description of distortions that the cable adds to the audio signal, the basic mechanisms responsible for the sound difference between cables are easy to describe. By understanding the following and by listening comparisons between different cables, you can easily learn the ability to properly assess a cable layout.
You can predict whether it is worthwhile to deal with a certain cable, so do allow yourself yourself to be fooled by nonsense, and learn a well-founded skepticism !!!
Miracles are still unexplained facts at the time of experience.
The earth is not flat, lightning and thunder are not generated by almighty beings, man is not from Adam and Eve, natural healing is not a witchcraft, radioactive radiation is unhealthy and electro-acoustics is physics ...... ..
The skin effect is one of the most important problems with cables. This often misused term refers to an actual phenomenon.
Often, it is believed that the skin effect is related to a power loss, and since the 3 dB point (performance bisection) for a cable is typically 50 KHz, there is no understanding that the skin effect is already in the audible range (20 -20,000 Hz).
In fact, the skin effect, long before it results in a power loss, has already caused changes in the values of resistance and inductance. These changes result in different frequencies impinging on different resistances which in turn vary in size depending on the distance from the surface of the conductor.
If a single conductor has too large a cross-section, the skin effect will cause different spectral components of the audio signal to behave differently. At any frequency, different portions of the flowing current will affect different electrical cable parameters.
As a result, this results in the fact that especially the critical, higher-frequency signal components sound smeared.
The ear does not note the details, mutes the dull sound, misses the openness, and the "stage" sounds flat. The signal power is still present, the frequency response has not been changed, but the information content of the signal has been influenced in a way that the mid-range range has been impaired.
There is a standard formula with which a current drop of 1 / e (= 63%) can be calculated over the cross-section of a copper conductor.
It is 1 / e = 0.0661: root of frequency, (m).
From this, for example, at a frequency of 20,000 Hz, a current reduction of 63% at a penetration depth of 0.467 mm and an extinction at 0.934 mm (18 AWG).
However, this formula does not describe the frequency at which the skin effect becomes audible. Careful tests have shown that audible disturbances occur even at a lower penetration depth.
It is therefore wrong to assume that a loss of 63% is an acceptable order of magnitude.
There is a solution to the problem of the skin effect: the use of a conductor whose cross-section is just so narrow that the current reduction towards the center of the conductor can not have any effect at all.
A cross-section of 0.8 mm is approximately the largest diameter in which skin-effect abnormalities are not audible.
Substantially thinner conductors do not mean any further improvement, but the problems listed below would come to the fore.
The silver wire, which is used in GERMAN HIGHEND cables in the relevant high-frequency range, has a maximum of 0.75 mm.
Do not cause more problems than we can solve !!!!
Since a single 0.8 mm thick conductor is thus not sufficient as a loudspeaker cable, the task is to produce a larger electrical cross-section without introducing new problems.
If we now take a bundle with many thin conductors and unite in a cable harness, the entire cable string will be subject to the laws of the skin effect, i.e., high-frequency currents flow very well on the surface, while only low-frequency currents flow with increasing penetration depth.
The results of these phase shifts have been discussed above.
Unfortunately, it is also so that the individual strands and strands in a cable bundle do not always run in the same order. At the beginning of the cable, the conductors are distributed differently across the cross-section than in the center or at the end of the cable. As a result, the current must "jump" a thousand times in order to flow again at its surface with its high - frequency components. However, adjacent strands are not arranged in a perfectly conductive manner next to one another: contact pressure and oxidation introduce complicated electrical equivalent circuit diagrams whose filtering effect is of great influence on the sound.
Environmental processes (particularly in the case of car HiFi systems), also lead to a pronounced aging process, so that the acoustic properties deteriorate over time.
Magnetic induction is another serious problem.
As is known, each current-carrying conductor is surrounded by a magnetic field. In adjacent conductors, these fields act dynamically one after the other in such a way that - on the molecular plane - the individual conductors are "modulated" by neighboring fields, whereby the strongest fields are assigned to the low frequencies since they are transported with a larger electrical energy. The modulus of the other conductors modulate the other conductors, which in particular modulate the high-frequency signal components, thereby also changing the mechanical pressure of adjacent conductors, and the trapping current in a conductor bundle is also modulated induction to an almost insignificant minimum. It has now become clear why most of the good cables are made of "rigid" conductors and do not contain strand bundles.
The rigid conductor has no problems with mechanical modulation.
Magnetic induction is, by the way, the main reason why the separate supply of low-frequency and high-frequency loudspeakers of a loudspeaker referred to as "bi-wiring" is so beneficial to the overall sound. In the case of loudspeakers fed by a single amplifier but receiving their signal via bi-wiring, the tweeter gets its energy via a conductor, which has no longer experienced any modulation by bass signals.
The material quality also dramatically affects the sound of a cable.
Looking at the electrical conductivity of cables, copper and silver provide excellent properties, pure silver being superior to pure copper - but unfortunately also in the price!
Silver plated copper works very well in the digital or video area, but in the audio arena we again have the problems described above which result from the different conductivity.
The inexpensive copper is available in many different qualities. Of "pure" copper one speaks, if in 1 meter of a copper conductor approximately 4,500 copper crystals are contained.
In this case, the current must in each case exceed the limits of these crystals, producing distortions which are the same as those arising during the jumping of the current in bundled strands. The first quality grade above the copper described here is oxygen-free high-conductivity copper (OFHC). The way these conductors are drawn reduces the oxygen content to approx. 40 ppm (compared to approx. 235 ppm with normal copper). The lower oxygen content considerably reduces the oxidation between the copper crystals and reduces the occurring disturbances. In addition, this copper succeeds in quartering the number of crystals, which in turn reduces the disturbances. The sound of an OFHC copper cable is softer, cleaner and more dynamic than the same cable design with high purity standard copper.
The next higher degree of purity of a copper cable is LGC or long-crystalline copper. These conductors are drawn with the utmost care in a process which allows max. 200 crystals per meter. Cables that contain LGC have a clear audible advantage over OFHC cables in the same design.
FPC copper is again improved, which is drawn in a complex sintering process as a monocrystal with a length of approximately 200 m (the crystal length in a moving coil, MC pickup system is up to 1,500 m). The advantages are acoustically easy to spot.
FPC could thus be the measure of all things, but a new degree of purity of copper is emerging, FPC-6, and has only 1% of the impurities of FPC.
These impurities in high purity (99.997%) copper are silver, iron and sulfur with some proportions of antimony, aluminum and arsenic.
FPC-6 has a purity of 99.99997% copper with only 19 ppm oxygen, 0.25 ppm silver, and less than 0.05 ppm of other impurities. This improvement has a dramatic effect - and the ear is the exclusive measuring instrument for the limits of such high chemical performances.
Once copper has reached such a degree of quality, a further sound improvement is possible only through the use of high-crystalline, high-purity silver.
FPS silver is a superior material.
Unfortunately, it is very expensive, but the resulting transparency, sound colors and sonic vistas are incomparable.
The meaning of the entire loudspeaker cable structure
So far, we have looked at the problems of the individual conductor. However, the arrangement of a plurality of conductors is also important. If this neighborhood is not uniform in the mechanical sense, then the electrical properties of the cable behave equally unevenly, with the result that the signal is disturbed.
The arrangement of the conductors may be parallel or helical, each of these arrangements having their specific qualities: parallel constructions are good but expensive! Spirals have a particularly good 1 IF noise suppression capability and have a favorable relationship between inductance and capacitance.
A cable can have two or more conductors, the arrangement of these conductors determines their magnetic behavior among themselves in conjunction with cable capacitance and cable inductance.
Some people believe that capacitance and inductance are the only important parameters in cable design. Of course this is not so!
However, the filtering network composed of these passive values determines the frequency response and, what is much worse, the phase response of the cable. Although inductance and capacitance are by no means magical characteristics of the cable, it is very important that the two values are as small as possible.
There is a theory in the area of the cable design which states that the impedance of the cable is to be adapted to the impedance of the loudspeaker.
This can not succeed!
Although the impedance matching is a valid concept, as the lecture "conduction theory" has tormented every engineering student, the correct adaptation is that all impedance (i.e., active and reactive resistances), of the transmission path are adapted.
Amplifiers have no output impedance in the order of magnitude of the input impedance of a loudspeaker (in fact the amplifier developer is trying to achieve the opposite effect), and loudspeakers all have a completely different input impedance, which also changes above the frequency.
Interconnect cable construction (RCA, XLR, etc.)
If you have not read the first part of this study, you should make up for it now. Many of the described problems exist in applications of both low and high voltage levels. However, the evaluation of the problems differs a bit.
In low-voltage cables, there is still the skin effect, electrical induction, magnetic induction and material problems.
However, the effect of mechanical modulation is significantly reduced, proportionally to the low flowing energy.
(Lower energy quantities> weaker magnetic-induction field)
On the other hand, however, the electrical behavior of the dielectric (insulation), is far more important.
The dielectric behavior determines how well or poorly a particular material absorbs or transmits electrical energy, and this has a great effect on the music.
Unfortunately, the technical term "dielectric constant" does not describe the reproduce-ability of the musical signal. Considerations for propagation speed and damping behavior are somewhat more helpful. The problem with the different dielectric is that the insulation acts as a capacitor next to the conductor. In it, this insulation stores energy, and then releases it a little later. The ideal conductor therefore has no other insulation than a surrounding vacuum. But if a solid material has to be used for insulation, it should be electrically "invisible." The less energy it absorbs, the better the energy absorbed should remain absorbed (e.g., heat converted). The energy that is reflected again should be reflected with as little phase shift as possible over the entire frequency range.
The most common insulation is PVC, polyethylene, polypropylene and Teflon. These can be foamed with air or attached to the conductor in a manner which includes a maximum air quantity. Both the material and its application dramatically determine the performance of a device cable. PVC is the simplest insulation material as it absorbs the most. Polyethylene, the most commonly used material, absorbs less energy and causes fewer disturbances. Polypropylene is electrically "harder" and has a better acoustic response. Teflon is the best available standard material.
The cable capacitance is more important for interconnect as well as for loudspeaker cables. There are two reasons for this: If a long, high-capacitance interconnect cable is used, many preamplifiers are no longer able to supply the cable with sufficient energy. The resulting interference does not occur in the cable, but is caused by the use of this cable.
The other reason for the preference for a low capacitance cable is that a large cable capacitance establishes an electrical field between the positive and negative conductors, which means that more energy flows into the dielectric material.
Important Facts About Cables
Like all audio components, cables also require a "burn-in time". Cables will improve their sonic characteristics after they have been in operation for about two weeks. At about this time the electrical behavior of the dielectric stabilizes, an effect which also occurs in the electrical components of the system.
All cables are direction-dependent in use, from the simplest copper cable from the hardware store to the most expensive silver conductor. Normally, cables are marked so that they can be used in the optimum current flow direction. If this is not the case, only one thing helps: Listen to the test! The difference will be clear. Used in a particular direction, the cable sounds more relaxed, more pleasant and more believable. This phenomenon has not yet been clarified to the last instance. So far, however, it is already known that the crystal structure becomes unbalanced when a wire is drawn, resulting in a different, direction-dependent electrical behavior.
Many high-quality loudspeakers can be operated by "Bi-wiring". A suitable loudspeaker has separate inputs for woofers and mid-high speakers.
Bi-wiring is used to reduce the interference caused by the low-frequency signal in the cable.
In a Bi-wire operation, the cable leading to the tweeter no longer carries the load of the magnetic field associated with low frequencies.
It is important to take advantage of the bi-wiring when the loudspeaker developer has added the possibility.
By the way:
If you use the ghastly gilded metal bridges that are part of most Bi-wire speakers, the loudspeaker may sound worse than if it had only one input !!!
Use the possibility of bi-wiring !!!
an also do not use the cheap accessory cables, which are often in the carton even with high-quality components ....
The investment in expensive bi-wiring adapters is surely to sound better than the sheet metal bridges, but can be referred to as physical nonsense and money-making compared to correct bi-wiring cables.
In the stereo application with cinch plugs, new problems arise with the spatial separation of the ground leads (L / R) of the 2 cables, which do not exist with the 5-pin DIN connector with a ground pin and common screen for both channels. If the cables are apart, the ground lines form a loop, into which foreign alternating magnetic fields, e.g., hum, or causing high frequency interference.
Some equipment manufacturers therefore still use the "good old DIN connector."
However, this can not be a satisfactory solution because the contact area of this plug is anything but sufficient and it is almost impossible to make high-quality cables correctly.
Remedy creates loose twisting, whereby winding right or left can supply different sound results, because the channels couple their signals differently (possibly undesirable secondary effect in stereo application).
A conductor rarely works alone ....
For current to flow, the circuit must be closed. In practical applications, cables are therefore two-wire, juxtaposed or coaxial. Special cables are multi-functional, for the position of the individual cores there are special rules depending on the application. On the one hand, the magnetic fields determine the structure around the conductors and between the two current-carrying conductors; on the other hand, the electric fields around the conductors are decisive for the cable design. Different wiring of the same multi-conductor lines usually leads to different results. With selected cross section versus number applications there are different overall losses.
The aim is to guide the conductors in the common field so that the usual loss remains minimal. A classic example is the "rule bar," two packets composed of several single-tones, a common axis.
Cables are made of metals such as copper, silver, aluminum, gold, or the metal-free carbon (manufacturer v.den Hul), either in the highest purity or mixtures or core conductors with coating of suitable metals. Oxides, inclusions, cracks, impurities have a negative effect on the rectilinear electron movement.
As the length increases, the eddy current losses increase.
Cable swing and vibrate.
Cables are subjected to mechanical pressure and vibrations in the sound field and react with microphones.
When it is compressed, the capacitance increases because the distance of the poles decreases, the voltage drops with the same amount of charge (U = Q / C).
As the length increases, the problem of the microphone increases because more mass is in motion, energy is stored and delayed, becomes sluggish. Also, the (soft) insulating material changes under pressure its density, its derivative, and its dielectric properties. Under the influence of a loudspeaker sound, a heterogeneous external intervention results in many cable parameters.
Cables generate electricity
Cables have piezoelectric effects, they themselves produce voltages from impurities of the insulating material with water. (humidity in the air penetrates).
Therefore, some manufacturers seal the leads on the reel or the plugs after soldering
As the length increases, the risk of piezoelectric effects increases.
Cables charge themselves.
The insulating material charges against other surfaces (e.g., carpet floor). This electrostatic effect also affects the sound behavior of the cable.
As the length increases, the effect increases.
The more distance from interfering materials, the sound is more airy.
Cables are antennas.
They capture foreign electromagnetic fields. They are protected by shielding, which can be differently structured and strongly influence the result. The cables are twisted against magnetic field influences, shielded against electrical fields with braid or film. A massive copper shield can also shield against magnetic components if it is thick enough (> 1mm). How the amplifier reacts to residuals of high frequency at the input, is another chapter ...
Shields also have tonally negative effects ......
Cables have a direction of rotation,
This can be explained by the manufacturing-induced change in the crystal structure and the assembly, stranding. In the case of a seemingly symmetrical structure, it must also be taken into account that a capacitance between the positive pole and all the other surrounding matter parts behaves differently from the negative, earth pole opposite the surrounding matter (which may be regarded as ground, earth), of the same polarity. Symmetry in behavior can therefore often not be talked about, since the circuitry of the electronics introduces different reaction problems (example: loudspeaker cable). Recently, the opinions have become more and more conspicuous. Robert Harley's research on the jitter of drives and cables shows clear differences in the running direction of digital cables in the measured jitter value. Differences in RF (radio frequency), noise were investigated by the Swedish manufacturer Supra. The direction-dependent behavior at high frequency is also shown in the shielding effect and is used to explain the differences in sound in audio application shields which can also have different effects depending on the direction of the signal, whether they are connected to the useful current or are connected only on one side, whether they are then flowed through with the interference signal, which then nevertheless enters into the conductor (keyword: coupling). Copper or aluminum shields with 100% degree of coverage or braids of copper, silver plated copper, conductive plastics, also combinations of aluminum foil covered with light copper braiding, the variety is surprising and the results are also different. The fact that the screen element elementally affects the electric field around the conductor, as well as the mechanical behavior of the cable, has a significant influence on the overall behavior of the cable. Where quasi-symmetrical leads are placed on the shield, it depends on the application and the cable material, structure. Coaxial cables leave no choice, here, the screen is at the same time return conductor for the signal and ground connection. In the case of multi-core constructions, a wire (2) equivalent to the signal conductor receives the return, ground connection and the screen is connected to the source or to the input of the subsequent stage. The quality of the screen is decisive for the screening effect: (maximum 100%), wall thickness and electrical material parameters to the crystal structure, in order to retain even the smallest components of electromagnetic waves from the conductors of the useful signal.
However, since the shields can also have negative influences (inductance, capacitance, etc.), some manufacturers (for example Eichmann) completely dispense with shielding.
The norm how they 'sound':
- silvered cables sound heavily sharp, aggressive
- silver cables are tonally balanced and natural
- cables from cheap conductor material are imprecise and "washed out,"... sometimes even distorted
- thick cables sound precise, crisp and 'slim' in the bass, but ... not precise and "washed out," in the high-midrange
- thin cables are precise and spatially in the high-mid-range, ... but more imprecise and "fat" in the bass range
- Litz cable are imprecise and "faded," in the high-midrange range
- solid conductor cables are spatially precise and detailed
The same physical principles also apply to connectors, circuit boards, components, etc.
(In part, however, "cable errors" can somewhat "cover up" the errors of the components, which can be falsely perceived as a sound enhancement).
Here are some more information: click >>>
(Source: G.Hilscher, Institute of Solid State Physics)
Before you put your money into the cabling of your system,
take a look at the frequency crossovers of your loudspeakers.
Even famous brand manufacturers are often exaggerated thrifty ......
An investment in high-quality silver cables makes relatively little sense if a 50 cent capacitor sits in the signal path in front of the tweeter ...
Also, the investment in the cables should be in relation to the capabilities of the existing facility.
A spoiler does not make a race car out of a compact car .....
Christian Reck (German Highend Silver Cable)
Jörg Erwin (A & V High-End Systems)