Higher sensitivity - more dynamic sound?

@audiokinesis How is 110 dB max SPL "more total dynamics" than 114 dB max SPL?

The only way I can see that happening is IF the system noise floor is at least 5 dB lower for the 86 dB/250 watt system, and that’s not something you have included in your example.

(Dynamic range does not start where the amp is producing 1 watt; dynamic range starts at the system noise floor. I mention this because, upon re-reading, one of your posts above seems to make that assumption.)

I appreciate this informative discussion. @audiokinesis  your detailed explanation for the inherent advantages of a higher efficiency/sensitivity speaker I find more compelling and logical compared with the counter position for the lower efficiency speaker expressed thus far in this thread.

What you have described/explained does seem to correlate to the actual listening experiences of what others here have reported.

Charles

Frankly, any reasonably well designed and mated combination of speaker and amp can be sufficient.

Consider that most rock /pop recordings have a whopping dynamic range of maybe 10db. Classical will have the widest range, perhaps 30 db.

Good dynamics is not just about the range of capability.  It is more about whether, when the signal goes up, there is a corresponding increase in the output of the speaker (i.e., no compression).  This is less the case with low efficiency speakers because, more watts have to be delivered for any given volume level, and a bigger proportion of those watts are being dissipated as heat.  The problem with this heat is that heating of components increases resistance which reduces the flow of current/power.  In other words, there is not a proportional increase in driver output to the power being delivered to the speaker because of such heating.  This is thermal compression and it is a bigger issue with low efficiency drivers which, dissipate more of the power being sent through the driver as heat than is the case with high efficiency drivers.  

Ok, obviously I’m dog paddling in the deep end … but if the amplifier has a very large - let’s say infinite - current capability, so can maintain voltage to be applied as the speakers impedance changes with signal frequency changes …?

[I have a lot of reading to do]

@inscrutable wrote:

"if the amplifier has a very large - let’s say infinite - current capability, so can maintain voltage to be applied as the speakers impedance changes with signal frequency changes …?"

A constant-voltage amplifier will put out reduced wattage into a higher impedance.  That's just the way that type of amplifier behaves. 

However a constant-power amplifier will put out essentially the same wattage into the speaker's impedance even as it changes, at least within a realistic range of change. 

Most tube amplifiers have a constant-power characteristic, and therefore the system's dynamic contrast would be less sensitive to heat-induced changes in the drivers' impedances. 

Duke