Is there any truth to this question?

Again, with inefficient speakers or speakers that present really difficult loads for amps, one must take that into consideration when purchasing an amp and really review the amps specifications and try them out personally before purchasing. The amp is designed to drive particular loads under particular circumstances and the size of the room, acoustics, distance from the speakers are are included into the decision. Just how hard does the amp has to work to drive the speakers. All speakers are not the same because their load impedance changes over frequency and power bandwith and the amp used must be able to handle that cleanly and operate within specifications. I would have a very hard time purchasing an 86 db "efficient" speaker unless I knew for sure that the amp to be used could handle the room and speaker. This is where being in the amp of the month club comes in. experimental purchasing without in-home demonstration. Which frustrates so many that want to get into this "hobby". But the more efficient the speaker, the less power I need to drive it. Hence 10 wpc amps driving horn speakers and you are blasted out of the room at 10 watts. Speakers move air and for traditional drivers, to move air means that the actual driver has to move. To move that driver takes power. How much power required depends on the load of the speaker, the speaker's efficiency rating and the room size and acoustics.

enjoy

Unsound..There is a couch behind the wheelchair and there is no place to back up to. You are right the Vandys are somewhat dark sounding and the Krell can be as well. When I bought the YBA preamp and amp the guy told me take them home for a week or so and pay me if you like them. They don't have the tight bass of the Krell but they provide a synergy with the Vandersteens that works nicely. The are brighter than the Krell and help to balance out the sound. I've had them for 15+ years and never thought to ask if there is something more until I heard the Music Reference RM 10. Again they are fairly low power but they just do things right with the Vandersteens. This goes against popular wisdom that Vandersteens need power because they are inefficient. My taste is to listen at a pleasant volume I've never pushed the speakers hard. I was an audiologist by trade so I know how a little volume over time can do damage to ones hearing.

Digepix, sounds like you've found your answer. Good listenig.:-)

I think the thread has run its course regarding OP, but the theoretical discussion continues - I'll stand by the position that an amp circuit sounds its best when asked to produce less rather than more power - and if the power thus produce is adequate to drive a speaker, the better we are served. Give me a great sounding speaker capable of 89db or higher, 92-94db or more preferable, then the ability to use as 15-30watts amp makes for audio nirvana. I know, lot's of ifs.....

I like 'the amp of the month club'. Never joined, never will and couldn't pass the physical!

However, given 2 identical impedance measuring speakers....they will react very differently to the same amp based on::
1. Phase data for the speaker. Reactance kills
2. Amps ability to drive such reactive loads.

To your last point of 'how much power is required' please add speaker reactance. Just my opinion, but the 'low impedance' / 'low sensitivity' = bad load thing has been repeated so often that as wrong as it is, has become a form of truth.
A dozen or more posts back, somebody drug Harbeth into the discussion. Low sensitivity? yes, in general. But easily driven by a 50x2 tube amp. The Harbeth? generally low reactance. 'Tube friendly', perhaps.