Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion HiFi & HT Chat The Old Snake Oil topic

Here is my experience:

I heard that cables sounds different and was sceptical, and I get highly sceptical with power cables.

I speak about power cables with enough conductive surfaces and no voodoo built in-just like regular power cables shielded or unshielded.

What should they sound different? Beside you can measure simple things like resistance, "how" can it be that a cable makes a different sound?

So a friend of mine and I was always on the typical "war",
"I hear it clearly and it have to be better as it's so expensive"
and
"no real logic why 1m lenghts of a "good" cable can make a sound difference when the main power lines are thousand of meters lengths".

Finally after my friend trying multiples times to make hearing test and and a bets, I accept as independent if I win or loose, we drink some good wine.

Biased as I had been, I heard no or maybe a difference. But my interest was started as I am a mechanical and electronic engineer with about 22 years in semiconductor production/maintenance/development, all my power was to find out that there is nothing to find out. Make it short, today I hear differences on power cables, sometimes very slightly or none at all, sometimes very big sound differences.
That is also depending on the absolute level of the audio equipment. Of coarse we did try trustable tests like blind tests.

Today I know that one meter of power does make a difference, because you add 1 m electrical circuit (the cable) behind the main transformer and that influences of coarse other circuit "before" the main transformer. One reason is that the "impedance" (the electrical resistance in relationship to the frequency) of the cable is different from one to the next. It's not only the main frequency (50/60 Hz), it is also the sound frequency (music) from the electronic device that is played/amplified or better said, the current of that frequency that the device need at that moment.

In theory, a power supply should be a short circuit for all frequencies so the internal impedance for the amp itself is not frequency dependent-it should be a "perfect" power supply/source.

In theory a correct designed power supply should not "see" the power cable in terms of impedance or a a filter as it designed correct.

But practice is different.
A popular underrate is the small amount of disturbance that can cause a different sound. So even say 10mV (mV equals 1/1000 V) disturbance on 115 VAC main line could be hearable-why?

The "signal"/noise ratio- 115VAC to 0.0115 VAC is a ratio of 11500 to 1. So what? - but measured that in dB is 81dB in volts or in terms of electrical power(voltage multiplied with current) 40dB.

So it's not "easy" or "shortlogic" to decide what is hearable.
I am not claiming here that it's "logical" that every cable have to be sound different, I only want to show with the example above that things are also get underrated.
Of coarse a expensive cable dont have to be sound better as it's expensive, but it could be sound better.

ONLY your ear and your "free" mind decide- nothing else.

My friend and I proved our personal biasing when we replace or just swap a cable without telling .Then we just listen to known music, talking, drinking and almost always the other party say: "something is different with your sound".

A good test is when you listen critical and find very small changes in sound and not to be sure what is "better", just playing music and make something else beside. After some time the "inferiority" of sound or disturb your concentration on your work or simply jar on the nerves and you like to switch the music off.

But that is a test for very slightly differences.
I hope my English is good enough to explain my experiences.