I wanted to go over my theory on power distribution and one way power cables can easily make an audible difference in your system. I have read a lot online about installing dedicated power circuits from your service panel to your audio system. This post will go over why you want to run ONE circuit, and power your system from ONE receptacle. This will also explain how your power cables can make an audible difference in your system... I have heard a lot of theories but this is very simple and almost always overlooked.
First, lets look at a simple, rather poorly drawn
diagram of what the connections between the ground planes of your components might look like when they are plugged into two different receptacles in your house. I often hear about running a separate line for power amps, this makes things even worse
than the diagram below. The diagram below assumes the 2 receptacles are on the same circuit. If they are not then the ground will only be tied together at the service entrance, which makes for an even longer ground path.
You can see in the diagram above that there are 2 paths tying the components' grounds together, the interconnect cables and the power cables + the ground wire run in between the two receptacles. Any potential difference between the components' ground planes will cause current to flow in these wires, including the "return" from signal transmission. The return path is being shared by the interconnects and power ground. Noise generated by potential differences in ground planes is a function of the resistance between them, so adding a bunch of wire and connectors in your house's electrical system to this is not ideal, nor is having the return path include this wiring ideal, and this is the reason power cables can be audible. Nothing to do with AC power transmission at all in this case!
In the diagram below you will see what it looks like when you use a single receptacle and power distribution block. Now we have eliminated the ground wiring in the house's electrical system from tying the components' ground planes together. We have also greatly reduced any chances of potential differences between grounding points, since there is now only ONE point where the system is grounded to.
I have heard other people suggest that the power amp should be the only component grounded, but this is dangerous as it increases the impedance of the ground path in every other component and is likely against code to "lift" the ground of a component that is meant to be grounded. The interconnects may not provide a low enough impedance path to ground, meaning the safety ground may not function as well as it should. Some IC cables use very thin ground wire and the internal wiring inside the component may also be of insufficient gauge to provide proper safety grounding. This is ok to do as a test to find issues but should not be a permanent arrangement, and if you follow my advice here it should reduce any effect lifting grounds will have.
In the diagram above you can also see that the power distribution block has the potential to protect your equipment from surges... including surges generated inside
your house by electric motors starting and stopping, such as washers, dryers, dishwashers and refrigerators. These devices also produce noise, which could be filtered out by the power distribution block. I hear a lot of people wanting to put a whole house surge suppressor on their service inlet, which isn't a bad idea, but those devices are MOV-based and noisy, so again, it's best for your power distribution block to eliminate surges and filter noise.
This is why I have bought a bunch of SurgeX power distribution systems, which I will refurbish and upgrade using higher quality wiring, connectors, and receptacles. SurgeX devices feature a surge elimination system that is non-MOV based and patented. SurgeX's customers include Carnegie Hall, Yankees Stadium, The Kimmel Center, NASA and more. The 2 devices I have chosen are the SEQ, a 20 amp capacity unit that features sequential startup and shutdown with 3 timed banks of receptacles and one always on bank, and the SX-1120-RT, which is basically the same without sequencing. http://www.surgex.com/products/rackmount-sequencers-product-line.htmlhttp://www.surgex.com/products/rackmount-product-line.html
In the near future I will start a thread on the above SurgeX units, and exactly what my plans are to refurb and modify them. I am doing nothing to change their function, I am simply replacing parts that are worn out or have the potential to wear out, such as electrolytic caps, receptacles and 1/4" female disconnects/push-connectors. They are the best industrial power distribution systems available, I am simply improving their performance for use with high resolution home audio equipment.
The information above also should have an impact on interconnect and power cable design. My cables have been designed with with the above information in mind, and as a result I often hear that my cables lower the noise floor of the system they are used in. This is very much an intentional facet of my cable designs.