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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
mahgister's avatar
mahgister
12,987 posts
 
Has anybody ever wondered by no two loudspeakers sound alike? Assuming there is only one accurate sound, that would mean that everyone except for maybe one company has it wrong.
Sorry but this is completely non sensical...

First "accuracy" is a complex chain of measured numbers, for example in the standard processing of designed pieces of electronic components, but "accuracy" in this sense had "no audible signification" except to certify that a piece of electronic component was rightfully designed....

Then the "accuracy of a sound" is in no way synonymus with the accuracy of an electronic design pieces or the accuracy of the audio system and the accuracy of sound is never reducible to them for his only source and cause...The "accuracy of sound" is a phenomenon mainly linked to the relation between the audio system and his embeddings linked to the ears/brain evalutation...

Then "assuming there is only one accurate sound" is a sentence with absoletely no meaning....And accuracy of a sound in music, is not accuracy in the acoustical sense...Timbre for example is not reducible to tone accuracy only...The accuracy of a sound produced by an electronical design in a laboratory has nothing to do with the accuracy of a sound in a room...

The sound did not come from our speakers to our ears directly in a pure delivery without any noise from any source, but on the contrary is the results of a complex acoustical interaction with the room....More than that the audio system is immersed in the mechanical dimension, in the electrical dimension and in the acoustical dimension, then the sound coming from our speakers is the signal/noise complex chain that is modified by these constraint i called the 3 embeddings....


Then your conclusion is also totally absurd because saying that all companies have it wrong is , like someone who want to recreate the wheel, especially, a non circular wheel....All company have it all relatively right in the limit of the trade-off implicated by electrical and mechanical constraints in the design of speakers and the choices they made...There is no perfect speakers, there is some better than others for some ears and for some goal....

Sound quality, timbre experience, imaging etc all these qualities come from the audio system in his totality embed in a specific room , in a specific house, and in a specific electrical grid..

Someone who think that human experience of musical sound come from the speaker design mainly is beside his shoes...

Why there is no 2 speakers that sound like each other?

The list of reasons is so numerous that reducing it to  difference in electronical design and mechanical design of speakers is very misleading...

But in audio thread the electronic design importance veiled for most eyes/ears the importance of the embeddings...

A piece of electronic design cannot work optimally in a non controlled environment.... Is it not simple?


mahgister's avatar
mahgister
12,987 posts
 
 There are so many varied considerations in speaker design that it is difficult to be versed in all of them. So, we are left to art and our own devises, hearing. We all have our theories and preferences which is what makes this fun.
I concur tough with the rest of your post...

Sorry if i seem rude....Anyway you dont read my posts anymore... 😊

My best to you....
bdp24's avatar
bdp24
9,787 posts
 

At the time Bill Johnson was starting his Audio Research Corporation (1970), his reference loudspeaker was doubled pairs of the KLH 9 Full range ESL (two 9’s per side). High-sensitivity loudspeakers were very available at the time (I heard the ARC SP-2 and D-50 driving a pair of huge bass reflex speakers in ’71), though the new small---and rather insensitive---acoustic suspension designs (pioneered by Acoustic Research with their AR-1 and -3) were quickly becoming the norm. But the sound quality provided by the KLH 9 was preferred to all of them by Johnson (and J. Gordon Holt of Stereophile), this in spite of the fact that the KLH 9 was an extremely insensitive design, and presented an insane load for the power amp (highly capacitive, with a ridiculous impedance profile).

Johnson then heard the new magnetic-planar made by fellow Minnesota resident Jim Winey, the Magneplanar Tympani T-I, and declared that it made the KLH 9 now unlistenable. While the T-I did not possess the high capacitance and impedance characteristics of the KLH, it was even more insensitive. Is there a more power-hungry loudspeaker than Maggies? Once again, Johnson’s reference speaker was an extremely insensitive design. He so liked the Tympani he offered to distribute Magneplanar through his dealer network. Yes, while Maggies present a load to power amps that more sensitive designs don’t, they also create a sound none of them do. The same is true of large full range ESL’s. Pick yer poison!

phusis's avatar
phusis
1,196 posts
 
@audiokinesis --

This is almost exactly what I’m working on, and had hoped to introduce in 2020 but... stuff happened that year...

Anyway I designed a large-format Oblate Spheroid waveguide using Earl Geddes’ equations, like you targeting a 700 Hz crossover to twin 15" midwoofers. That 700 Hz figure is consistent with the findings of David Griesinger which Geddes subscribes to, and is very close to the 800 Hz crossover that Greg Timbers uses in the JBL M2. Imo the ability to cover the spectrum from there on up with a single driver is a major advantage over more "conventional" approaches, in addition to the other advantages of large drivers and high efficiency.

And of course the way around the bass extension/box size/efficiency tradeoff relationship is to hand off the bottom couple of octaves or so to subwoofers.

I’m rather surprised by how similar our approaches are. I knew we were barking up trees in the same forest, but didn’t realize it was the same tree!

That is certainly interesting re: the similarity of approach, and thanks for your added/confirmative info here! Indeed, covering the whole frequency span from ~700Hz on up from a single driver/waveguide/horn element appears to be paramount. The current driver/horn constellation (and soon to be fitted with a bigger horn) of my main speakers sport a 2" exit with a 3" titanium diaphragm, and thus lends great energy and "breathing room" to its lower to central region. This does affect the upper octave however compared to smaller exits of 1 and 1.4" which don't roll off quite as early, though conversely at the expense of lower band energy and higher distortion here. Choices, choices; it's a matter of balance (and preference) with the implementation at hand, but I find it's worth the effort compared to adding another driver element, cross-over and point source.    

If I may inquire: what's the intended waveguide exit size of your upcoming design, and would the twin 15" bass/mids be configured D'Appolito style or with both of them below the OS waveguide? Btw, I'm thinking whether Timbers would've preferred a slightly lower cut-off than 800Hz with the M2's, but that the size of its waveguide simply won't allow it? Scaling up the size here likely would've made for a bulkier, and less commercial appearance. 

To the OP: sorry for veering off-topic. If nothing else what's elaborated above is an indication of a preference and a desired high eff. design path that seems less popular or visible not for reasons of lack of sonic prowess, but rather size requirements and design principle in particular. Few audiophiles appear interested in compression drivers and horns/waveguides, not to mention larger pro woofer/mids that extends into the central midrange; I'd wager it's largely conjecture aimed at a speaker segment that doesn't speak the conventional hi-fi narrative, and where auditioned their typically denser and more direct/present sounding nature mayn't appeal to those who're usually exposed to a leaner, more laid-back and softer/reverberative presentation. 

And may I just add: high efficiency doesn't automatically equate into easy or easier amp load. Less power is stored into heat for a given SPL, but a complex passive x-over here can still drain amps with less prodigious power supplies. For easier an more optimal amp load active configuration is required. 
phusis's avatar
phusis
1,196 posts
 
@mijostyn --

Good post, but I'd have to disagree with below quote:

A low sensitivity speaker can be very bit as dynamic as a high sensitivity speaker. It is just a matter of power.

Sorry, but no. Anything approaching live dynamics calls for both high efficiency and power (with very high eff. all-horn designs less power is needed). It's not only a question of achieving fairly uninhibited SPL's and dynamic envelope, which in itself is no easy task, but doing so with headroom to spare - on the speaker as well as amp side. Indeed, headroom is your friend and aids ease of presentation. Of course, less than live dynamic levels would do for many, but even then (with low eff. speakers) headroom is likely sparse. Power is power, and where less efficiently turned into acoustic output is stored as heat and eventually power compression.  
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