[Amps] Class A for AM

[kenw2dtc]

Wow, I had the computer off for a bunch of hours and when I logged back in 
there were a number of very informative answers. I thank everyone for the 
information, and it's causing me to do more reading on Class "A".

Looks like a number of responses were centered around 6000 watts based on 
25% efficiency. (1500 watts / .25).

Now lets say that one wanted to keep this amp chugging during the summer 
with possible line voltage sags, is it reasonable to assume that a tube with 
even more dissipation would be needed to maintain the desired output?

In the same vein, as I look at some of the tube specs, the linear portion is 
not at the full range of plate current, it appears to be especially 
non-linear at the low end. Does this mean that it may require a much larger 
tube than one with 6000 watts of dissipation because the class "A" bias 
setting would have to be set near the middle of the curve where the current 
is higher?

73,

Ken W2DTC