How much amplifier power do you really need?

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Sorry, missed this earlier.

I'll start with the second question first.  Power is not power.  Power is the measure to do WORK or the potential to do WORK.  In the strictest sense (as it applies to electronics) power is the amount of work that is needed to move electrons through a given medium.  When fewer obstacles are present electrons are more free to move and thus more work is needed to keep them moving.  The converse is also true, when more obstacles are present electrons are less free to move and therefore less work is needed to keep them moving.  So unless the system requires large amounts of power less will do.  How can anyone tell how much power they need unless they measured it?

What you have defined is energy.  Power is the capacity for work per unit time.  Never mind, it doesn't have that much bearing on the discussion.

One of the interesting points of the video was that it did indeed measure instantaneous power delivered to the load.  To be really explicit, the meters on the amplifiers showed the amount of power needed to drive the speakers with a faithful (undistorted) signal at the set volume level.

GOOD, power that is sufficient in supply at any given time for any given load.

CLEAN, power that is free from artifacts inherent of the architecture's design and components.

LINEAR, as the demands for power increase (instantly or continuously) the supplies of power also increase in lock step.

None of those qualities are inherent to power in itself (where do they appear in the definition of power?).  Of course I agree that they are desirable characteristics of an amplifier.

The problem with the video is that it does not indicate what the conditions are at that "instant".  What is the load when the amplifier displays 350W?  My example amplifies the problem when snapshots of power are taken out of context.  I made the assumption that the load was 6 ohms the instant 350W was needed to prove a point.

The video shows that the amplifiers are delivering up to 600 W per channel peak power into the load at some points.  Assuming the amplifier knows how to properly measure the peak power it's delivering, the power is just what the meter shows it to be whether it's into a 1-ohm, 3-ohm, 6-ohm or any-other-ohm load.  You don't have to make any assumptions whatever about the load -- or any other "conditions", for that matter -- if you believe that the amplifier is designed so that the peak power meters are accurate.

How can you conclude that an amplifier needs 100 times more power available for peaks when we don't even know what those peaks are?  That's purely conjecture.  You cannot solve what you do not know.  Again how do you know?  You need to measure.

It's not my conclusion.  It follows directly from the definition of crest factor, as explained in the article I linked to, without any interpretation or assumptions on my part.  Neither is it conjecture, unless you disagree with the values of crest factor that are quoted by that article and other independent sources.  I am not trying to "solve" anything, in your words.

I suspect our conversation has gone beyond the point of being interesting or useful.  You're welcome to continue if you wish but I will bow out here.