Watts! How many do we need?

@immatthewj   I think that Sanders covered this question fully in his paper? 

@bigtwin  , I am honestly not familiar with Sanders or the paper you referenced, but is it accessible on this site?  What would I need to use (besides "Sanders") as a search engine to find it?

@immatthewj  Scroll up about 15 posts and you will see I pasted a potion of the paper and included a link to the full paper.  Sanders does a good job explaining the perceived difference in tubes and SS, and why many systems may be underpowered.   Once again, I am assuming he knows what he is talking about after designing and building amps and speakers for decades.   For me anyway, he calls into question all the members who claim only fhe first watt is important and that 50 watt amps are all you need.   Read the whole paper and tell me what you think.  Cheers. 

The Sanders white paper is excellent. The two big takeaways are 1. that transient power demand is far higher than we think or that anything short of an oscilloscope can measure and, 2. the recovery time of the power supply in responding to transient power demands is critical.

"is an unltralinear watt identical to a triode watt? That’s a serious question, I am not intending to be sarcastic."

Basically, yes. But ultralinear operation has plusses and minuses. and a lot of those depend on the quality of the output transformer, the percentage of the screen taps relative to the plate taps, etc. You can get essentialy twice the power of triode operation (or more) but you also introduce stability and distortion factors that must be addressed. In a typical feedback amplifier, switching from triode to ultralinear operation requires adjustments in the feedback components to optimize the amp’s performance and stability. So a big question when buying a switchable amp is, does switching from one mode to another involve correctly adjusting the feedback components to allow for optimal performance? An amp oprimized for triode operation can encounter some serious issues when switched to UL mode, and vice versa. If no such arrangements are made, then one mode or the other is going to suffer. Often times, people with switchable amps will report that they tried the triode switch but didn’t like it because the sound quality was reduced. Or, they’ll report that triode mode was more "open" but the bass control was worse, etc. Usually these negative impressions are the result of the amp not being properly designed to optimize each mode of operation.

@bigtwin thanks for the Sanders white paper! An excellent read.