How important is the efficiency of a speaker to you?

@lonemountain   While I would agree that sensitivity alone is not a indicator of quality or sonic virtue in loudspeakers, it certainly is an indicator as to what one can expect as to choosing an amp that will work well with said speakers. As such, the number and type of amps that will work is now significantly diminished, and as pointed out above by atmasphere, said amp will almost certainly NOT be working at its best. It also pretty much removes certain types of amp designs...mostly in the tubed genre.

@lonemountain wrote:

When you say that efficiency is not the most important aspect of performance ...

I wrote it’s "not the only" important aspect. These last ~15 years I’ve avoided low efficiency speakers as anything I’d consider buying (with the exception of seriously considering at one point larger and active ATC models, in particular the SCM150ASL Pro’s (and ultimately the SCM300’s, had economy allowed)), but efficiency as a standalone parameter isn’t as much the true indicator vs. what it leads to design- and size-wise, and so it’s really the other way ’round: the designs I prefer are mostly horn-based and large, and therefore, in effect, high to very high efficiency as well. It’s not that I can’t enjoy the sound of many a low. eff. design, quite to the contrary, but I’m simply pursuing a different route with different strengths sonically compared to what smaller, more inefficient and passively configured speakers can deliver.

I disagree that efficiency is the "preferred route" in achieving lower distortion, improved dynamics or increased bass. There are so many other avenues to these features.

Fair enough, but coming down to it we’ll have to disagree on this one. Yes, there are other avenues and areas of importance here that can make a low eff. package sound indeed very good in named areas, but when higher efficiency enters the "equation" to boot (again, not as the only parameter as anything worth considering) the significance in performance - to my ears and sensibilities - is not trivial.

ATC is a notable exception here, to an extend, in that their engineering prowess in driver development and overall execution is on another level compared to most lower eff. speaker manufacturers (and thus, and this needs to be stressed, they’re hardly representative of the low eff. segment of speakers). Active config. only adds to this advantage. The SCM150 and SCM300ASL Pro’s - that I’ve auditioned quite a few times - are excellent speakers in their own right that I could easily live with, and yet a large horn-based system (not least actively configured) does something else both dynamically, with regard to ease(!), scale, presence, immersively, viscerally and bass delivery that you’ll have to experience to fully understand and appreciate.

I did not say that low eff. designs avoid the limitations of poor efficiency simply by adding more power. There may not be limitations of lower efficiency designs, depending on your goals. Or there could be limitations of a high efficiency design.

Different contexts will have things in variables, yes, but getting a true bearing on a more complete wallop and significance of uninhibited dynamics, low distortion imprinting and smooth, effortless bass prowess at more than moderate SPL’s and shorter listening distances will require setting a different benchmark; to some these very aspects aren’t main priorities, let alone secondary, but to others they’re quite another connoisseur matter and will necessitate measures that goes beyond smaller, passively driven and low efficiency speakers.

I think the whole array of solutions are far more complex than high or low efficiency "spec" on a spec sheet. Whether something is 92dB 1w/1m in a loudspeaker gives you zero information about quality when compared to a 86dB 1w/1m spec.. You only know the designer chose to chase efficiency (probably for more than one reason). Intended application is everything..

Chasing efficiency in itself would seem crude, but let’s make it actual high efficiency to begin with if we really want to refer to it as such; my understanding of high efficiency, all along, has been a sensitivity from 95-100dB’s on up. Few designs really accomplish that, and if you intend to have a fairly uniform and controlled directivity pattern at the vital crossover(s), not least crossing low enough to avoid the central midrange while maintaining sensitivity all the way down low to the 20-30Hz region, then you’ll have yourself a large sized package that can really show its mettle with the parameters referred to earlier.

Some lower efficiency designs can achieve lower distortion in the driver, or can extend low frequency of that driver or both. Or your lower effieciency design may improve cooling and power handling without extending voice coil length. I guess to me its like horsepower tells you zero about the performance of a car. There are so many different options available to a skilled designer that focusing only on a high efficiency design is not wise, again, depending on your goals. I favor lower distortion myself, I want to hear more of the fine details, the reverb tails, the room sound, etc. If I can have lower distortion that reveals more of that fine detail in exchange for a larger power amp, I’m in. That’s the trade off I am talking about. And I’ll stick to my guns on this one, you cannot have it all.

And this is where we are ultimately disagreeing. Within the design differences inherently at play here I do believe we can more or less have it all; care taken with a specific design is not limited to low efficiency dittos, and if you’re willing to go the distance and let size and physics have its say, it means upping the potential of such designs even further. No, I wouldn’t cram speakers that large in small rooms, but contrary to common belief they can be implemented excellently in moderately sized listening spaces - not least actively.

@daveyf  you also have to consider that tube amps with high sensitivity speakers also limit many tube systems because of noise and hiss which you can't hear as well with low sensitivity speakers. Not all tube equipment is quiet, just like not all high powered amps sound bad.

@daveyf

You are right about the amp issues regarding hi vs lo efficiency designs, well said. Yes, a low efficiency design might require more power.  But these issues are truely complex and trying to make a blanket statement that some performance related feature is always good or always bad doesnt really work in audio. People long for universal truths, but in audio, the truth is conditional.

Brad

Gents, I think we can summon up the above posts with this: It is extremely important to acquire a speaker that has a good synergy with the amp that powers it.