Higher sensitivity - more dynamic sound?

@jhills --

Making this about low efficiency speakers/higher power SS amp vs. high eff. speakers/low power tube amps is not the strictly defined combo context here, but rather low vs. high eff. speakers - certainly per the OP. It makes sense using low powered tube amps with high eff. speakers (and vice versa with low eff. speakers), but you get lots of the benefits with high eff. speakers no matter the amp principle. Myself I use a combination of class A and class D solid state coupled actively to my high eff. speakers, and from my chair bypassing the passive filter is the real treat with the benefits it offers with digital filter settings to more readily accommodate horns with steeper slopes, etc.; not whether tube amps are used instead of SS.

Re: playback volume, it’s a common misconception that high SPL capabilities (with high eff. speakers) necessarily equates into the need or want for high SPL playback. To me at least it’s generally about how it sounds at average SPL’s (i.e.: ~65 to 90dB range) and how the segment of speakers I’ve chosen excel here, but with the added bonus of a greatly enhanced, effortless dynamic bandwidth, in addition to prowess into transient capabilities and overall presence and physicality of reproduction, whether at low or high SPL’s. It’s not about clearing the roof over my head with +120dB levels, but the incentive to listen at higher SPL's with speakers that can handle it cleanly with ease and powerfully is not diminished, I might add.

And let’s expand a bit on ’effortless’: headroom is your friend - can’t be re-iterated enough, it seems - and that even more so when we enter LF territory. You want 105dB clean peaks at the listening position you want headroom to spare, not just merely enough, and this goes for speakers as well as amps. So, when I say my subs can put out ~127dB’s at the LP down to almost 20Hz, that’s not to say it’s my desire to actually achieve those levels - far from it - but once you hear bass reproduced effortlessly at every desired level, headroom makes sense.

@jhills wrote:

"... it seems a bit irrelevant unless you are listening at live concert SPLs (104 - 115+ db)."

In my experience freedom from compression effects is audible at pretty much all volume levels, including low levels, which is where I normally listen.  I never listen at anything approaching "live concert levels", and only rarely listen "loud". 

Duke

Lonemountain- why did you arbitrarily start at 102 db volume for the high efficiency speaker but 86 db for the lower one? The more efficient one can also of course play @ an 86 db level using a small fraction of a watt & thus probably w/ extremely little amp distortion. Both speakers can have the same dynamic range assuming a sufficiently powerful enough amp for the lower efficiency speaker. The high efficiency speaker can achieve it more easily, likely quicker too & w/ much less required power

Last word in efficient or not, I prefer the big open and natural sound of electrostatics and planers over boxes, hands down, but that’s just my personal preference.

My favorites over the past many years was a pair of (not so efficient) Apogee Duetta Sigs. driven by a Mark Levinson 333. Not everyone’s cup of tea, but was mine.

If all I wanted was loud, forward and dynamic I’d buy a Jukebox.....Jim

@jhills --

Last word in efficient or not, I prefer the big open and natural sound of electrostatics and planers over boxes, hands down, but that’s just my personal preference.

Absolutely fair.

Being natural representatives of the (very) high efficiency segment: do you have experience with horn speakers, be that horn hybrids or all-horns? Tall large-horn speakers can have a sound reminiscent of large panel speakers, certainly akin to a limited dispersion "big open and natural sound" you’re describing, and a sound that sets itself apart from smaller, low efficiency box speakers in general. Not trying to convert you into being a horn freak (I suspect that attempt would be futile), but just to break down more stereotypical assumptions of their characteristics as being in every case from the same piece of sonic cloth. With horns in particular, size matters, but few want to accommodate that in their homes.

If all I wanted was loud, forward and dynamic I’d buy a Jukebox.....Jim

I hope that’s not your condensed takeaway from what high efficiency is necessarily about. By contrast a jukebox is only representative of that: a jukebox.