Power cord? Why?

Eldartford: Many of your suggestions are valid and are exactly what should be done by those designing / building the gear to begin with. As such, i would have to say that we are probably on the same page / line of thinking, but our actual experiences differ.

Besides that, the ESR of some capacitors at 20 KHz will be MUCH higher than you think it is. Regardless, the ESR doesn't really matter to RFI since the caps are in parallel with the power supply and the RFI can "ride right over the top" of them. You acknowledge this in your post when you mention digital gear "pumping signal" back into the AC lines. After all, such a signal would have had to have either been radiating into all of the circuitry in the box and using the power cord as a feedline OR the circuitry was actually modulating the power supply and feeding signal back into the AC system. Both are distinct possibilities and realities and i think that you know this. That's why i want YOU to experiment on your own and see for yourself just how "under-designed" most of this "high end" gear really is.

Theory aside, your first hand experience will probably change your mind about things. I'm not saying that you will become a power cord convert, but that you may better understand why some people talk about actually hearing sonic differences. The approach that you mentioned i.e. better filtering and design of the power supply, is the right approach in my mind. Reducing the potential for RFI and other "pollution" entering the gear through the use of more technically advanced yet reasonably priced power cords can only help the situation though. Sean
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Okay Bomarc. I'm on the same page now. Thanks for your point of view.

Twl: As Audioengr mentioned, some batteries will be better for this than others. As a side note, this is the reason why some car stereo enthusiasts employ LARGE filter caps very near their amps. The caps themselves can discharge and supply power faster than the battery sitting very near it can. This is due to differences in the internal resistance of the devices themselves. While some caps may be worse than some batteries, caution must be used when selecting such a cap. Very careful selection of batteries and placing them very near the device drawing the current may negate the need for any support components such as caps, etc..

I'm curious as to whether or not you've ever tried anything like this ? The main things that i'd look for if you did was greater bass impact with greater punch / clarity on peaks. Sean
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Sean, I'm currently using a large capacity lead acid automotive battery with 650 cold cranking amps, located about 24 inches from my amplifier. I have the terminals directly connected to the power input barrier strip on the amp, with 12ga OFC copper stranded wire.

I have not tried any capacitors on the power connections as of yet, but the idea has crossed my mind. I was thinking that since my amp only draws 3.1 amps @ 12vdc at rated power, I figured that the 650 cold cranking amp capacity of the battery could handle that. From my listening observations, this amp really has some balls in the bottom end and dynamics, even though that may sound comical with only a 2 watt SET 45 amp. But it really is true. This amp has alot of punch, and it makes those Lowthers stand right up and get with it.

Another thing that I have done, is to use a separate battery for each of my components, so that there is no modulation of the power supply of one component by the draws of the other. This seems to make a difference. Individual power supplies take the idea of "dedicated AC lines" further into the isolation of each components power supply totally from the others. I like the effect of it. It's clean.

I'm still working on doing whatever I can think of to ensure the cleanest, unencumbered power to my components as I can possibly do. I think that the flat DC, with no intermodulation between components, full isolation, and high current availability has improved my sound.

Sean...OK, here is a test that will be easy to do.

1. Get 2 monoblock power amps (I have a pair of Kenwood LO7Ms which should suffice).

2. Get 2 "super" power cords. (The Kenwoods will need modification to use them. The original cords are, I admit, crummy. Strange for such a well made piece of equipment. (Maybe they properly designed the power supply!)

3. Using the super cords, play the same music signal into both amplifiers. Adjust gain so as to minimize the voltage difference between the HI outputs of the two amps. If everything was perfect this voltage would be zero.

4. Record the voltage. If possible I will use a 100sps bench type precision A/D. With this type of data I can make plots and even perform Fourier analysis of the signal.

5. Now, replace one power cord with a "crummy" one.

6. Repeat the test procedure.

If the differential signal is the same as before, the "crummy" power cord has no effect. Note that while this test procedure does not involve subjective evaluation of sound, it does examine the amplifier audio output that drives the speaker, which is closer to a listening test than measurements of power supply voltages.

Now...what should I use as the "super" power cord. Please suggest wire type and configuration(s). Any other comments/suggestions are welcome.