Shunyata Factory Tour - and how do THESE claims hold up?

[Speedskater]

Now, if you could invent a magic AC power cord that as almost zero (end-to-end) impedance below 6000 Hz and very high impedance above 10,000 Hz that would be great.

 

[egellings]

Now, if you could invent a magic AC power cord that as almost zero (end-to-end) impedance below 6000 Hz and very high impedance above 10,000 Hz that would be great.

What's available in bog standard power cords is more than adequate for the task.

 

[Travis]

Thanks to all who ventured back into this thread from awhile ago to help a non-engineer try to understand some technical double speak by a manufacturer.

Just had to point out this clip from the page where they describe their test and have the graphs we have been discussing.

They mention “three critical performance criteria” but only describe two. Guess it didn’t meet the third.

Language at the bottom of the graph says “Note: Lower is better” but not for that graph. Higher is better.

Make of that what you will.


CLIP From page on DTCD:


The DTCD® Analyzer allows the measurement of pulsed transient current through a variety of AC power products, including power cords. The measurements represent three critical performance criteria:

1. The quantity of instantaneous current available through a specified power device or circuit. Measured in amperes.
2. The amount of voltage drop across the device during the conduction period.

 

[Cbdb2]

So you get larger inrush and pulsed current spikes to charge the caps. Which is harder on the caps, and means more EMI noise to deal with. And your rail Voltages will hardly change, unless your power amp is running at full power. And if that's the case, you have bigger problems.

 

[antcollinet]

More to the point, the different lines are tending to different DC currents - Red to about 130A, and blue to around 230A. Rise time looks to be similar suggesting a similar inductance.

Assuming the same voltage pulse is applied then it implies simply a different DC resistance. If a generic cable as measured by Amir is about 0.13ohm, then the venom 3 is around 0.7ohm.

Both are fine for AC power even at the maximum current of about 16A (the generic cable will drop around 2V, the venom around 1V). Neither will impact the audio.

 

[Speedskater]

So you get larger inrush and pulsed current spikes to charge the caps. Which is harder on the caps, and means more EMI noise to deal with. And your rail Voltages will hardly change, unless your power amp is running at full power. And if that's the case, you have bigger problems.

Except that you don't with 50/60 Hz AC power. Those charts are in the high megahertz range.

 

[Cbdb2]

Except that you don't with 50/60 Hz AC power. Those charts are in the high megahertz range.

Im talking about analog power amp supplies where the PS caps are charged by current pulses. The lower the power grid impedance (which includes the power cables ) the higher the pulse current. I realize the cable dosnt make much difference, but if it did, as they imply, then this might be a problem.

 

[antcollinet]

Im talking about analog power amp supplies where the PS caps are charged by current pulses. The lower the power grid impedance (which includes the power cables ) the higher the pulse current. I realize the cable dosnt make much difference, but if it did, as they imply, then this might be a problem.

What @Cbdb2 is pointing out is that with the 50us time shown on that graph, the 60Hz rise time would be almost a horizontal line (50us is 1/333 of a mains cycle, and especially near the peak when the capacitors are being charged). In other words the rise time of the mains waveform is so slow compared with the limited rise time from the cable inductance that it will have absolutely zero impact.

 

[RayDunzl]

What @Cbdb2 is pointing out is that with the 50us time shown on that graph, the 60Hz rise time would be almost a horizontal line (50us is 1/333 of a mains cycle, and especially near the peak when the capacitors are being charged). In other words the rise time of the mains waveform is so slow compared with the limited rise time from the cable inductance that it will have absolutely zero impact.

Shhhhhhhh!

We're not supposed to know that.