Nicely written! I enjoy your perspective. When you say that efficiency is not the most important aspect of performance, you and I are on the same page. I disagree that efficiency is the "preferred route" in achieving lower distortion, improved dynamics or increased bass. There are so many other avenues to these features.
I did not say that low eff. designs avoid the limitations of poor efficiency simply by adding more power. There may not be limitations of lower efficiency designs, depending on your goals. Or there could be limitations of a high efficiency design. I think the whole array of solutions are far more complex than high or low efficiency "spec" on a spec sheet. Whether something is 92dB 1w/1m in a loudspeaker gives you zero information about quality when compared to a 86dB 1w/1m spec.. You only know the designer chose to chase efficiency (probably for more than one reason). Intended application is everything..
Some lower efficiency designs can achieve lower distortion in the driver, or can extend low frequency of that driver or both. Or your lower effieciency design may improve cooling and power handling without extending voice coil length. I guess to me its like horsepower tells you zero about the performance of a car. There are so many different options available to a skilled designer that focusing only on a high efficiency design is not wise, again, depending on your goals. I favor lower distortion myself, I want to hear more of the fine details, the reverb tails, the room sound, etc. If I can have lower distortion that reveals more of that fine detail in exchange for a larger power amp, I’m in. That's the trade off I am talking about. And I'll stick to my guns on this one, you cannot have it all.
Brad
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