SO POWER CABLES MAKE A DIFFERENCE IN SOUND?
Many people just cannot believe it. After all it is just a powercable. And why would it matter while outside of the house there are literally hundreds of kilometers standard wire in the power grid? There are multiple possible explanations, but really sufficient at explaining the large differences that exist they are not.
In general the last few meters of cable are more important than the kilometers ahead of it. At least, as long as there's a decent cable. If there would have been a thin cable running from the powerplant to your house, you bet you would've heard the negative effects of it! But since the European standards for electricity are based on safetly before all you can be sure that at least the cable used should be well specified and will not be a power limiting factor.
THE FINAL METER
The final meter to the component definitely has the most infuence. This can easily be confirmed in practice. A separate cable from the extensionblock to the meter (consumer unit) already does less for the sound. If you would somehow insert a high end power cable somewhere in the middle of the wiring between meter and final component, you probably wouldn't hear much of it. The infuence of a powercable and with that the largest difference in colour or transient speed is most clearly audible at the end of the chain. But why should this be so? The usual explanations don't even sound very convincing to me but I also don't know how to effectively explain this. I guess it's just like many phenomenons in the hazy world of high end audio. Sometimes you just have to admit that it's there, even though you cannot understand it. So even if you don't believe it, please just try it out for yourself and see if you hear a difference.
Some components are less sensitive to this than others, for example the Wadia 861 cd player is extremely sensitive to power but the Mark Levinson no.390s cd player is comparatively immune. It can also be that the speakers used don't have enough resolution to clearly demonstrate the differences. Most of the time however, the human himself is the problem. Often people listen for difference in only one parameter. That could very well be just the parameter that doesn't change. Also most people are most sensitive to changes in colour while powercables more often than not make the most difference in perceived speed, attack or liveliness. It is important to keep an open mind and listen unprejudiced to any possible diferences. I'm sure that you will hear some difference. You may not find the difference large enough to worry about but that's another matter!
ORDER OF THE CONNECTORS IN THE EXTENSIONBLOCK
Try experimenting with the order of the connectors in the extensionblock. Most extensionblocks are internally serially wired. That means that the first component (at the cable intry) has the most direct line and every sequential component is "filtered" by the cables and components prior to it. Some people are convinced that the most power-hungry appliances (amplifiers) should be first because they need most power. Others claim that this is not wise as the amp consumes all the power, starving the other components after it. Both claims are theories and both have some truth to them, but in practice you will just have to experiment. Some components sound absolutley terrible if they are last in line while others really benefit from the added coloration when connected at the end of the extensionblock.
In my experience the first component in line always gets the most attack and directness. It is least filtered by other cables and components and therefore most tight and lively. This can of course be a good thing but also a bad thing. The following positions in the extensionblock offer increasingly less tightness and attack but progressively morre roundness in the bass and more fluidity in the highs. This effect is amplified by the type of cables used. So a warm sounding cable will not only make the atached component sound warmer but also the adjacent components connected further down the line in the extensionblock. The first component is also infuenced, but not as much. This all is a very handy tool in order to tweak the sound to your liking!
IT ALSO MATTERS HOW THE PLUG IS ORIENTED IN THE EXTENSION BLOCK
Phase is also a not to be underesimated factor for the resulting sound. This is only applicable for those countries that us reversible connectors so the UK and US don't apply. But if you can, just try it out: swap the orientation of the Schuko connector in the extensionblock and listen for changes in forwardness and speed. Most likely, you will hear a difference. One position will probably sound more lively and upbeat than the other. Never mind for now which is better. If you want to take the easy way out, just choose whichever pleases you most.
Then there is such a thing as correct phase, assuming the manufacturer of both cable and component have done their duty, the IEC end of a power cable and the male connector in the component should already have a matched connection. All you need to do is to make sure that the schuko side of the cable is oriented in the proper position in the extensionblock.
HOW TO IDENTIFY CORRECT PHASE?
Method 1: by ear
By default I tend to say: use your ears. Especially because the correct connection doesn't neccesarily have to match your situation, components or preference. But if you have many components this can be a lengthy process. That's why I provided the following easy procedure to at least make sure that all cables are connected in the official way.
Method 2: the most simple method for finding the correct phase
The official side for phase is as follows: Looking at the IEC connector from the bottom, having the lump on the underside, the left hole should be live (carry the phase). Also see IEC connector types and correct phase. If you don't want to do further testing, just connect everything this way and more than likely you should be fine.
Now that you know where the phase should be, insert the cable into the extensionblock en use a voltage meter or a simple screwdriver with lightbulb to find where the phase is in the IEC connector. When phase is at the wrong side, just reverse the schuko in the extensionblock. Repeat these steps for all power cables. Then you've done your part. Hopefully the manufacturers have done the same. Usually they have, but not always. I've even found 2 matching mono poweramps wired up opposite! That's why you're best off doing it by ear. If you like measuring, there's method 3.
Method 3: the measuring method for finding the correct phase
For this you need a sensitive multimeter, a grounded outlet and a non-grounen outlet (or cheater plug).
1. Disconnect all components from each other (interlinks as well) and the power.
2. Connect 1 component to the unearthed oputlet, still not connected to the others.
3. Meaure the voltage that exists between the earthed outlet's earth and the chassis of the component you're measuring.
4. Reverse the schuko connector and measure again..
The lowest measured voltage indicates the proper phase.
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