High current power cables

To me it is a quandary how so many knowledgeable people don't understand the current needs for an amp.  I use 10ga power cables (not expensive ones) on all my amps.  I recently bought an amp and the seller provided the "upgraded" power cable he had been using.  I looked it up and it was more expensive than any power cable I have ever bougth.  It was 17 awg.  I am confident this power cable is why he ended up selling a fine amp.   Also,  I recently bought a small tube amp (differtnt amp), 10 wpc push pull, 14lbs total. It had poor bass performance and I assumed that was because it was such a small, low power amp.  I was powering it with a 14awg power cable.  After several days a friend suggested putting a 10awg cable on it.  Bass fixed immediately.  I'll never use anything smaller than 10 awg on an amp again.  It is not a big expense to put a generic 10awg power cable on your amp.  And if you still have problems, bypass any filter or regenerator.  Plug directly into the wall and do a test.  If that makes it sound better, then replace whatever you have powering your amp.  Power to an amp in very, very, very  important. 

@bigtwin Thanks for posting. That is exactly the simple (and correct as far as it goes) understanding that causes people to buy too small a cable.  If you go by your amps power rating, lets say 200 watts, then you need less than 2 amps. An ampacity table will tell you that 26 awg is all you need.   Can you imagine a 26 gauge power cord?  A small to medium amp would run on it--and sound like crap.

In reality, your load is dynamic, not static.   You need to be able to change current values very quickly.  It isn't the steady state current that sizes your cable.  That is the steady state calculation you posted. 

But if people keep using power cables sized the way you calculated, there will be used amps for sale for the rest of us to buy.

Jerry

@bigtwin I know you wouldn’t suggest that, I’m just saying that the logic of calculating power cable size based on Average amp load would say it will work. And 12awg likely will be just fine. Some power supplies have large capacitor banks etc and may be different in their needs. But realize your meter will always show the average current. I do see a sub in the background. Sometime subs are a result of poor speaker performance at low frequencies, sometimes poor power cords cause poor bass performance. Finally, sometimes it is a personal preference. I’m guessing yours is personal preference. I’ll try to attach a photo of my system, which uses no subs for 2 channel sound and with 6 wpc, some tubes give me too much bass.