Low-sensitivity speakers — What's special about them?


I'm building a system for a smaller room (need smaller bookshelves), and I did a bunch of research and some listening. I am attracted both to the Dynaudio Evoke 10's (heard locally) and the Salk Wow1 speakers (ordered and I'm waiting on them for a trial). I have a Rel 328 sub.

Here's the thing — both of those speakers are 84db sensitivity. Several people on this forum and my local dealer have remarked, "You should get a speaker that's easier to drive so you have a wider choice of power and can spend less, too."

That advice — get a more efficient speaker — makes sense to me, but before I just twist with every opinion I come across (I'm a newbie, so I'm pathetically suggestible), I'd like to hear the other side. Viz.,

QUESTION: What is the value in low sensitivity speakers? What do they do for your system or listening experience which make them worth the cost and effort to drive them? Has anyone run the gamut from high to low and wound up with low for a reason?

Your answers to this can help me decide if I should divorce my earlier predilections to low-sensitivity speakers (in other words, throw the Salks and Dyns overboard) and move to a more reasonable partner for a larger variety of amps. Thanks.
128x128hilde45
Low sensitivity is a trade-off small size and deep bass to bigger size and not as deep bass.
Low sensitivity causes thermal compression that makes heavy, constrained, tiresome sound.
High sensitivity speakers, in contrast, produce easy going sound like a real musicians on stage performance.
It is sad, but a big part of audiophiles don't care about  thermal compression despite this phenomenon kills a real musical reproduction and makes music boring and tiresome.
Regards,
Alex.
It’s not just about bass, one needs to consider the source the root causal reason for higher output.

one form of higher output is achieved with a mechanical device to focus energy - imo at cost to fidelity. Horns are not everyone cup of tea. Since to appear focused on dynamic drivers, I will comment more about those..

for dynamic driver speakers, non pistonic motion creates higher output thru constructive and destructive interference. Check out the Utube video on the comparison of two 5” midrange, for a dramatic and easy to understand visual representation of in and out of phase behavior. That video is linked on the Vandersteen website. For a non pistonic driver ( most of them frankly ) A great deal of output is just in and out of phase trash. When a pistonic cone assy is fitted to the driver with equal mass, output drops. The bottom line is trash counts in the efficiency measures. Another reason to listen and not get too wrapped up in less than critical specification. Pay attention to impulse response tho!
IMO a fantastic speaker for you would be Vandersteen VLR signature on Sound Anchor stands with a Vandersteen Model 3 subwoofer with 11 bands of analog EQ for perfect bass at the listening position and a built in amp that takes load off your main amp yet preserves transfer function of the main amp

I've not bought any power yet. Thanks for the replies. I understand the technical trade offs better, now. If one had the bass covered by a subwoofer, it seems there’s no positive, specifiable, aesthetic reason to prefer low sensitivity speakers. I think that captured every remark so far, no?
+1 tomic601.  I have installed a  pair of Vandersteen Model 3 Subwoofers.  They are sublime.