Some self appointed Hi-Fi Specialists will threaten personal damage to me, but physical laws cant be changed by laymen and self-appointed Hi-Fi freaks

Read your self:

Well known Hi-Fi magazines refused to publish it, I believe for them it is more important to receive advertising orders from the suppliers of super expensive ineffective speaker cables (i.e. more than € 400,- per meter........

The truth about Speaker Cables

From Peter Weber / DJ4BR

It is understandable that Hi-Fi enthusiasts and music lovers likes to spend lots of money to improve the sound of their Hi-Fi equipment. Also the speaker cable are considered for this, because they do have a influence to the sound. Due to this often "special extremely good cables" are offered on the market for extremely good sound perfection and extremely horrendous high prices. Prices of more than €500,- per meter are not seldom. In circles of experts these offers are called as brainwashing of the people and overreaching, but never someone did protest against this.

Again: Which cable shall I use for my Speakers?

A simple rule of thumb is: The cable should be as short as possible and so thick as I can pay for. It may certainly come from a building centre!

Here is a chart you can see the effect of the wire cross section and the cable length to the attenuation factor and the power loss of the cable.

From 1000W of an audio power amplifier connected via a 20m long cable with a cross-section of 0,75mm2 to a 8 Ohm speaker box, a power of only 895 W will reach the speaker, the rest is converted into heat in the cable.

However if we are using a cable of 4mm2 cross-section the cable loss is reduced to 2% only, so from 1000W now 980W will reach the speaker and only 20W are lost in the cable.

One can easy see, that on short cable lengthes already a cross-section of 0,75mm2 can be used successfully and who want to make it even more better, can use cross-sections of 1,5mm2, 2,5mm2 or even 4mm2, have than the very best result for a good price.

Don't forget the damping factor: What is the damping factor? The damping factor is the relation of the speaker impedance to the internal resistance of the Hi-Fi amplifier. An average amplifier has an internal resistance of i.e. 0,08 Ohms, at a speaker impedance of 8 Ohms the damping factor then is i.e. 8 : 0,08 = 100.

This value should be kept by using adequate selected cable (see chart). In case a amplifier has a lower internal resistance (resulting in a higher damping factor), effects of overshooting will be suppressed and limited by the speaker membrane build in the speaker box. This results in a better sound, so the sound will be more direct, more natural and clearer.

In practical one should keep in mind, that inside the speakers is strong needle eye build in with a strong influence to the damping factor, the coil of the cross-over network is normally wound with thick wire, but easy has a resistance of 0,5 - 1 Ohm, this can never be compensated even by the most expensive speaker cable.

Material:

Cable made of special "oxygen less" copper is offered on the market. One supplier wrote, that his cables are "sounding transparent, sterically and shining airy in the treble range. Clean depths and basses are rounding the sound image. Technically all frequency ranges are clean, realistic and linear presented and displayed."Thus if the cables are sounding, we need no speaker boxes any more. Such expressions in leaflets, advertisement and data sheets are poor rubbish and idiocy.

Skin effect

Some speaker cable suppliers praise there cable with a very low Skin effect… Yes that's right, but the cable from the hardware store also has no skin effect at audio frequencies 20Hz…. 30kHz.

What is skin effect?

The skin effect is the tendency of an alternating electric current (AC) to distribute itself within a conductor so that the current density near the surface of the conductor is greater than that at its core. That is, the electric current tends to flow at the "skin" of the conductor. The skin effect causes the effective resistance of the conductor to increase with the frequency of the current. Skin effect is due to eddy currents set up by the AC current.

However a measurable skin effect in the range of HiFi audio frequencies (20Hz…30kHz) is not at all possible. A skin effect can be measured at high frequencies above 1.000.000 cycles per second (thus 1MHz). That is the reason, why in the radio an communication technique partly silver plated wires are used for the coils. But within the audio frequency range its absolute not necessary, see also: [Meinke/Gundlach, Taschenbuch der Hochfrequenztechnik, Springer-Verlag 1968, and Curt Rind, Handbuch für Hochfrequenz- und Elektro-Techniker, Band 3, FT-Verlag Berlin, page 208, 240, 597]

Cable inductivity, Cable capacity

The cable capacity and the cable inductivity are forming in principal a low pass filter. The value of the capacity is on a 1m cable max. 300pF. In case you use for the inductivity a value (relative high) of 10nH (nano Henry), it results in a cut-off frequency of higher 90 MHz(=90.000.000 Hz), so its within the Radio-FM band. This really far away from the range of audibility and also from the range that can be handled by the amplifier. So we donot need to care about the capacity or the inductivity.

Summary: Purchase in rest low cost twin litz wire (ca. 1-3 Euro per meter) instead of expensive "special cable" and spare your money for better speaker boxes, that's much wiser.

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