Power Cords Snake Oil ??


Having been a long time audiophile living with countless high end compnents I have to wonder about the theory and practicality of high end power cords.

I have yet to hear the difference a power cord makes. Ive owned, synergistic, Shunyata, BMI and cardas. I in no way can detect any sonic signature or change. Give me a pair of interconnects and I imeadiately notice a difference somewhere in the sonic spectrum. Not the PC though. I have accomplished 4 blind tests with my friends. 3 out of the 4 they did not know their cord was replaced. All 4 were using a stock factory supplied cord. Each of the 4 tests were done on different components. Amp, CDP, Preamp & dac.

My electrical backround tells me that provided you supply the component with its required voltage bet 110vac or 220/240vac its happy. Now, change the incoming frequency from 60hz to say 53hz and watch how quickly your soundstage collapses.! This is often the case during the summer months when home air conditioners are in use and the utility company power output is taxed to the max. A really good power conditioner should however take care of the frequency fluctuations. But 110vac is still 110vac regardless of the conductor it passes through as long as its remains 110vac when it reaches the intended circuit. Does your 8k amp or preamp know the difference of the path the voltage took to reach it ? Many an audiophile will use a dedicated 20amp circut for their equipment.That is a good idea as voltage & frequency fluctuations will occur in the home circuit to to other loads on the main breaker panel but again, A power cord simply is the means of transporting the voltage from the wall to the component. IF there is a clean 110vac @ 60hz at the wall socket, no matter what the medium is to go from the socket to the component, it will still be 110vac @60hz.

Could somebody expand on this a bit more. I just dont understand it. ??
jetmek

Showing 3 responses by audioengr

The effect of a power cord depends entirely on the power supply design in your components. For instance, before modding my amp and DAC, they both improved significantly with low-inductance power cords. After modding I can use a wall-wart ppower supply on the DAC and a cheapo cord on the amp - makes no difference. This is because these components are no longer demanding high-frequency transient currents from the cord/AC supply.
Flex wrote:
"Audioengr, have you done a control experiment where you take your amp and dac to a city environment with really dirty power, fluctuating voltage, and rfi. Does the power cord independence hold for these conditions?"

I recently lived in Portland, OR, where the voltage does fluctuate, but it is nearly always on the high side. This is where I did this testing.

RFI has nothing to do with power delivery. The impedances are too low. It has to do with ground-loops that form loop-antennas at the resonant frequency of the RF.

High-frequency spikes on the power can cause problems, but generally these are filtered-out by the transformer banswidth.

Folks attribute all types of noise to RF and HF noise on the power. The reality is that these are often due to ground-loops and other sources.
Sean - I will try the zoebel experiment. What values do you recommend?