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Mistakes and ficton

Observations in advance

I do not concern in discussions about personal taste, opinions, preferences or other personal arguments.

If you make a decision and let yourself guide by your personal/own feelings, then indeed you have something what is ideal for you and you can be satisfied about it. But, this gives absolutely no definite answer about it's technical behaviour!
My only argument is that reproduction of audio/music (technically) must be as close as to 100% of the original recording, I consider that as good.
Also I don't feel the need for a 'yes/no' discussion, if someone has another opinion: very well. But I will react to untrue or even lies and technical wrong issues.
Example: if I (with very precise equipment) don't measure any difference, or measure differences significant lower than 1%, then it is unlikely that you can define this as 'clearly noticeable'.
If I define 'measureable', then I mean measurable parameters such as: amplitude, phase/duration, impedance, total harmonious distortion (THD) and spectral decay. All impact which ends up above 100kHz is ignored because the human hearing cannot observe this. By the way, there is absolutely no tweeter that can manage these frequencies.
If you don't search for the 'weakest' chain in the system and than try to solve that first, what are you doing? Trying to fix a non-existing problem?
Unfortunately lots of the audio-fanatics let themselves lead by their feeling and claim themselfs as a person with 'golden ears'. But why are there so many different opinions?
I can be very direct, it is not my intention to hurt someones feelings but this is my way of trying to make something clear.
In case you think I am wrong, well prove me otherwise. Reactions can be send on this page.

Some basic assumptions:


Fixation on one aspect

May be it is one of the major mistakes in the audio-world: the fixation to one aspect and forget that the whole audio-chain consist of more.
The initial attention is not bad as it is, but is it the weakest part? Does it have influence on the human hearing? Each system has its own weak points, so one universal solution does not fit to all problems.


Electrical power, more power is better

Wrong. Electrical power has nothing to do with quality nor does it say anything about distortion. Power is a very wide concept, does it describe RMS power, peak-power, continous power or what? So the term power does initial means almost nothing if not specified what it describes. Only form a commercial point of view it's an interesting argument of selling stuff.
See also the technical explanation about power.


Burn-in legend

Cables and electrical equipment has to burn-in for about 2 weeks.

Wrong! Give me 1 (just one!) technical reason what the changes are and why this affects the human hearing.
Until now, no one had proven me that burning-in has a well-founded cause.
There is a probable cause: psycho-acoustics. When you are focussed to hear something, you are psychical setup your mind to hear that effect. Which can be separated in 2 parts.
First: by listening very focussed you hear things you were not aware of, but what was already present. You can hear these 'things' if you always listen very focussed, but that is normally not the case.
Second: you (just) imagine you hear something new. When you listen to new or changed equipment for a longer period of time and you imagine that it sounds better, your mind is set to hear an improvement regardless if it is better or not.

So, is it really better or is it just your imagination; wishful thinking?
In this case you get used to a way of listening or to a certain soundscape. There is no need for technical improvement, as long as you think it's better! You are adapting to a different way of listening.
Someone said to me once about that burning-in: 'so, that cable is of such low quality that it is not get used to transport an audio signal'...

Burning-in of cables and electrical equipment is just a legend, totally nonsense.


Special interlinks

There are many claims that special interlinks are required of a much 'brighter' or 'cleaner' perception of audio. I don't dispute that such cables are theoretical and/or thechnical of higher quality, but are these effects really audible? Discussions regarding this must not get bogged down on supposed technical effects or superioir materials, but must lead to just this question: is it audible?

When you see the measurements and the differences between those interlinks, I can only conclude that the (supposed) differences as it is are hardly audible [note 1].

Briefly explained, pure silver does not add any clarity in audio, it does only lower the impedance by maximal 6%; all frequencies do benefit from this not only the high frequencies. Even audio cables and interlinks have to obey the physical laws...

In the real world only a few factors determine the signal behavious of any cable. It is the inductance, it's capacity and the cable geometry.
Theoretically spoken a coaxial cable (like RG-58) is no improvement in audio frequencies till 100kHz. Beyond that, I doubt if differences less then 1% are audible.
When you are looking for a good interlink, you can make one by yourself. Ingredients are a twisted pair or a piece of coax and a few (gold plated) plugs. It will cost you about 20 euro/dollar and it will work just like the expensive one's.
See the pdf-file 2aderig_interlink (sorry, dutch only) with calculations about influences in 2-wire cable, pdf-file rg58coax-interlink about coax and their relations to increasing frequency.
Practically the effects of attenuation the signal can almost be ignored because the relative influence is very low. Even at higher frequencies the effects are hardly 2%. What is the effect of a 10 Ohm rise when connected to a input impedance of 22kOhms? Yes indeed, it's negligible.

So be critical and realistic: can this be audible and is it worth any investment?
Summarized: the effects of 'special' interlinks or whatever cable, are very low (can be verified with evidence or proof!), so I really doubt the effects are clearly audible. So I don't exclude that there can be any difference, but they are not significant. Beyond that, influences are mostly caused by interaction, so attention to input and output circuitry must be taken into account also.

Interlinks has nothing to do with magic of myths, it is only physics.
See also the FAQ page or the page about interlinks.


Loudspeaker cable

In general the same effects are noticed as by interlinks. Well, if you're just looking at the factor 'cable'.

But there are differences in conditions.

First, the lenght of loudspeaker cable is more, sometimes by a factor of 10. Second, the impedance of a loudspeaker is significant lower than the input circuitry of an electronic device. So any influence in the cable wil have a relatively greater effect. Third, also because of the lower impedance of the loudspeaker and the required power level, a larger diameter of the wires is required to avoid losses due to the increased current.

Last but not least, the impedance of a loudspeaker is not as stable as the impedance of an input circuitry of an electronic device. Mainly the frequency dependancy will have a negative effect on it.

What really matters is the relation in impedance from the speaker cable and the loudspeaker: the relative influence and the frequency dependancy.

The major effect causing problems in loudspeaker cables is the self-inductance. In combination with the dc resistance of the cable and a non-linear load, it will give a certain frequency dependent attenuation.

The 'only' way of reducing these effects is to choose a large diameter of the wires and (optional) twist these wires. Other interesting stuff like OFC or teflon do not really contribute to the cable performance in the audio domain. It is initial a slight improvement of quality, but have no real provable audible effects.

See the pdf-file 2aderig_ls-snoer (dutch only) for an example of the influence of normal 2-wire cable of 2,5mm2 diameter. Be you own judge.
I have also a page loudspeaker wires with tests.


Mains cable, a good (shielded) cable for improved sound stage

Well, to be honest I don't think you can hear such differences at all. Because the assumed effect(s) are that small or even not present.
The acclaimed effects can be separated in: (A) magnetic influences from other devices, or (B) mains distortion or interference and (C) the ability to have pulse-power capacities for audio reproduction.
A: Magnetic influences on mains cable can almost be ignored. To generate an audible noise by induction, you need a large magnetic field which is not a realistic situation. Even though in almost every device there is a transformer present. And one of the characteristics of a transformer is that it's a large inductor. So even when interference is coupled in, the effects are minimal due to the filtering effect of the inductor.
Cliams that shielding prevents form magnetic influences are also not based on facts. When a magnetic field is coupled into a shielded wire, the shielding has to be of a minimal thickness because of the skin-effect. In case of a copper shielding and a disturbance frequency of 50Hz, the shielding has to be at least 1mm thick. Otherwise it won't work...
Shielding is only effective against capacitive coupling. But there are also other ways to avoid this, like using isolation of good quality. Also, use some distance between different cables (instead all together in 1 bundle).
B: Another story is mains distortion. This could have influence, however, when an apparatus and its power supply is well designed the resulting impact is  negligible.
In case there is some mains distortion, using a mains filter and additional X-type capacitors will do. Adapting a power cord to such distortion does not have a real impact because it has no filtering effect. It is more the opposite way around, a "worse" cable can help to attenuate high frequencies. So a custom made power cord could be counter-productive!
C: The impulse-power and sound image would improve by using a good power cord. The idea would be that if the power supply is very tight and stable, the audio playback also is.
But, the impulse-power can not be delivered by a transformer (one of the drawbacks of a large coil), so no improvement of a power cord can be expected. In order to be able to deliverd high current impulses, the use of (large) capacitors are required.
Then compare the self inductance of a transformer (tens of mH) with the zelfinductie of a 'poor' power cord (less than 2uH), the ratio is more than 1:5000 (0.02%). Do I have to explain myself further?
Mains filtering requires a total different appoach: when it comes to suppress distortion, only filtering will help. This is done by adding some series resistance and by adding parallel capacitors. Practically filering is done by coils and capacitors, where the ac-resistance thru the whole audible bandwidth very important is. So, to speak in general terms, there can not be any improvement from a power cord.
Think about this: why would you change only the last "few" meters of the power cord when there is hundreds of meters of cable from the power station?

Summarized and technically, it is all nonsense!
Is there any explanation? Yes there is: commercial interests and psycho-acoustics.

Vibration damping

Special vibration damping devices are used for much clearer and more spatial audio behaviour.
I do not discuss personal taste and preference, also not on the fact how well (...) such a damping device works. But claims that the audio signal will significant improve, are absolutely proven wrong.

The only function of a vibration damping device is to decouple the sound producing parts from its mechanical frame, so that frame will not radiate unwanted sounds. That vibration can be from an external source also.

To damp the influence of vibration, you need to use an elastic object in conjuction with the mass of the source.

In loudspeaker design there are 2 ways to avoid vibration, first is to decouple the radiator from the loudspeaker enclosure to avoid unwanted radiation of that enclosure, second the floor from the loudspeaker enclosure to avoid vibration of the floor.

In most of the vibrating sensitive cd/dvd players is an error correction present that compensates the impact vibration (well, at least to a certain value).

But that does mostly not correspond to the practical situation of supposed universal damping.

Many companies sell only universal vibration damping, but how do they know what frequency need to be damped, or what the mass of the device is? Without answering these questions an adequate damping is not possible (otherwise a lucky gess...).

I know one manufacturer that has made measurements on vibration damping, they admit that normally the damping in the range of -45 to -80dB is. Is you know that the dynamic hearing is about 65dB, than you will know that it has a marginal effect. And there must be an almost constant vibration to let one notice that effect.

Another misunderstanding is the use of spikes under loudspeakers. Because spikes are not flexible, they do not absorb energy and do not damp any vibration. It will only help to stablize the enclosure if the foundantion is relative rigid.

There is one exception where vibration could have a direct influence on the audio signal, that effect is called "microphony".
That is the influence on non fixed components like open capacitors or crystals. Vibration will change the structure of the component and its properties. If the property is changed, the net value can change and have some influence on the audio. When it is the case, is it more to blame on poor components.
So, summarized: as long as there are no reasobale large or contant vibrations and good quality components are used, vibration has very less influence on the audio signal and soundstage.


Due to Skin-effect special cable or coax is required

This is not true. Skin-effect does always exist, but starts at higher frequencies of the audio range. Generally the skin effect starts above 15kHz, from 35kHz it give also measurable deviations. From approx. 100kHz the influences are no longer negligible (in luidsprekers). The impact in audio range is almost neglectable because the effects are to high in frequency to detect.

Even tough, the impact at 100kHz is so low (within 1dB) that the predicted influences cannot be distinguished.
For analogue audio signals is certainly no reason to use special cables or coax.
A much heard misunderstanding is that this have impact to low frequencies also. This is incorrect. Skin-effect act only at high frequencies. 

Next parts will follow translated soon...

[1]: Research on objective limits of hearing: Leuven University (Belgium); Fraunhofer Institute (Germany);

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