Steve,
I know where you are coming from.
Widget,
All I can say is if you are still deciding on what you think right you still have not got there yet if you know what I mean.
I agree that some of the best speakers are quite dynamic and have quite amzing HF extension.
However, they (the best) only convey what they are fed being that the more ideal a speaker is the more efficient and effective it is in transforming the current from the amp into vibrations and sound.
Many people get confused about what they are listening to.
Is it the speakers or the power/pre amp?
Given the law of diminishing returns if your speaker is ultimately accurate what you end up with is what the amps are doing and this is one of the most perplexing aspect of audio to appreciate. Unfortunately too few have the opportunity to appreciate and compare what these differences are and it is assumed that the speaker system is to blame when in fact the amps are infact not blameless.
This is why I regard amplifiers as more important than anything else after arriving at an accurate loudspeaker. The amplifier amplifies voltage and current under dynamic conditions and one would be very niave to imagine they are perfect and they all sound the same. Two active devices with similar specifications can sound totally different and this applies to not just Valves and BJT transisters and Fets. Often large amounts of feedback are used it hide these non linearities but feedback brings with it its own curse by destroying the true dynamic transient character of music and an electronic glare which listeners refer to a listening fatigue.
In essense, a remarkable loudspeaker will often sound less flattering on the best amplification. As Steve said earlier, the excessive, distortion laden yet dynamically lacking highs are OFTEN passed off as detail.
Wrong.
A very high quality amp will provide more fine details, trasnients and transparency without ever sounding tiring. There is also a far less compelling tendency to increase the volume level to reveal more transients and details.
I think this is why many good vintage loudspeakers sounded good in the early days before the downward spiral of modern solid state amplfiers.
Fortunately this trend is reversing in a small way and we are seeing the rebirth of many classic loudspeaker systems using SOA amplification.