Speaker sensitivity vs SQ


My first thread at AG.

Millercarbon continues to bleat on about the benefits of high sensitivity speakers in not requiring big amplifier watts.
After all, it's true big amplifiers cost big money.  If there were no other factors, he would of course be quite right.

So there must be other factors.  Why don't all speaker manufacturers build exclusively high sensitivity speakers?
In a simple world it ought to be a no-brainer for them to maximise their sales revenue by appealing to a wider market.

But many don't.  And in their specs most are prepared to over-estimate the sensitivity of their speakers, by up to 3-4dB in many cases, in order to encourage purchasers.  Why do they do it?

There must be a problem.  The one that comes to mind is sound quality.  It may be that high sensitivity speakers have inherently poorer sound quality than low sensitivity speakers.  It may be they are more difficult to engineer for high SQ.  There may be aspects of SQ they don't do well.

So what is it please?

128x128clearthinker
So there must be other factors. Why don't all speaker manufacturers build exclusively high sensitivity speakers?
@clearthinker  Cost, in a nutshell. High efficiency drivers are much more expensive due to a greater degree of precision required to precisely place the voice coil in a narrower gap, plus a more powerful magnet system.
b_limo1, great video, have seen it once before. Interesting perspective.

tomic601, When you say "don't confuse low sensitivity with poorly engineered load". I feel they are closely related. And I believe this is John DeVore's point in the video. I know of a high end speaker that is rated at 90db at nominal 8 Ohms (2.83v at 1 meter), have listened to it many times at a friends place. But when you look at the measurements of that speaker it has dips in the impedance down below 3 Ohms as low as 2.6. The speaker maker is only telling us a partial truth with their specs. It is only a 90db speaker for some of the frequencies and in effect a much harder to drive speaker to pull out all the audible sound well. Which I believe plays into the issue pointed out on the video of 1W per meter vs 2.83v per meter can be deceiving. With this particular speaker, you need an amp that doubles down on power when you halve the impedance to sound right. In other words it needs an amp designed for low efficiency speakers.  
I own Mission Cyrus 781 speakers sensitivity rated 90.5 db...

I drive them with my Sansui AU 7700 rated 8 ohm 55 watts....

No problem....I can make deaf my neighbours.... They sound  very refine and bass powerful...



😊
+1 newres, well said. 

Speaker manufacturers ask for 10s of thousands of dollars,  play fast and loose with sensitivity numbers, and (usually) don’t publish any impedance graphs. Mostly we’re left to hoping that JA has tested the speaker and published results 

Hate car analogies, but here goes.
How much? $80k
Horse power? Don’t know
Torque? Hmmm, good question 
weight? Not sure...  
I'd go with mahgister.

AR 18s speakers (88dB) driven by a Rotel RA-414 amplifier (35W) can rock the place with 50-60 people whole night long and like that every weekend for years.

How much easier to drive you need them to be? I am sure there are armchair theories, but in real-use practice that is all one may need.

Skipping humongous speakers (Moabs anyone?) leaves more space to cram another few people in the room.