Why manufactures don´t burn in their amps and ...

Power cords are important when it comes to high power output devices.

True. But along the lines of Mitch2's comment, all of the effects mentioned in Ralph's post can be avoided simply by having adequately low resistance in the path between outlet and power amp. Which often may not be provided by stock power cords, but can certainly be accomplished via a modest upgrade that does not utilize exotic materials and construction techniques and cost megabucks.

We have measured nearly 3 volts in some cases. In a 100-watt amplifier that can account for a nearly 50% DROP in power!!!

Ralph -- Can you elaborate on how such a large drop can occur, and if that would hold true just for tube amps with unregulated filament supplies, or for tube amps with regulated filament supplies and/or solid state amps as well?

Thanks,
-- Al

True. But along the lines of Mitch2's comment, all of the effects mentioned in Ralph's post can be avoided simply by having adequately low resistance in the path between outlet and power amp.

An indeed that is what I have found to be the mystery around those extremely thick stock power cords that came with the higher powered power amps (at least those that I have been familiar with). Thick cable was not just all rubber/plastic but they came with thicker wires too!!!

Stewie: "(Mr. T): this hobby is so subjective that when you have 2 audiophiles in a room, you will get three opinions."

That's nonsense. You will get four opinions.

True! After the first one changes his mind, the other one will follow suit.

Shadorne: And indeed that is what I have found to be the mystery around those extremely thick stock power cords that came with the higher powered power amps (at least those that I have been familiar with). Thick cable was not just all rubber/plastic but they came with thicker wires too!!!

Nice to see that at least some of our members can bring a sense of humor to this subject :)

-- Al

A voltage drop on the power cord is caused by two things: the gauge of the wire and the quality of the connections.

If your power cord is heating up at the connectors, here is an example of why things like the Porterport or medical-grade connectors can make a difference!

The wire itself will heat up if it is inadequate gauge.

If it is built improperly, it can resist the high current/high frequency surges required at the peak of the waveform.

I think its a good idea to have a shield too.

IMO, building a cable carefully with good connections at either end and a heavy gauge will hit about 95% of what is important. We built a few power cords just for fun and they turned out quite well. Some of our gear does draw some power and they seemed will up to the task. After you build a few and add up the costs, you start to see why some power cords cost what they do. Not all though :)

First, there are NO high frequency 'surges' in a power cord.
If a power cord measures as highly reactive, you will have voltage and current not in perfect phase.
Just for a trivial example for which I have measures.
A 40 watt fluorescent light draws about .32 amp after warmup. The power factor (PF) is about .8, so the lamp really draws 40VA.
If the PC is such a load, along with the powersupply of the equipment in question, that can be the source of some bad effects.
The electric company really hates low PF loads, and at least in industrial applications, charges a premium.

As an aside, the same thing can be said of the amp/speaker relationship. A speaker with huge phase angles can suck the life out of an amp while having only a fraction of the power delivered to the load. Add low impedance and the problem compounds.