Is the most efficient speaker the best speaker?


Is the most efficient speaker the best speaker -- all other things being equal?
pmboyd
Atmsphere, of course that is only your opinion, many if not most, have come to the opposite conclusion.

Sorry, Unsound. What I have stated is simple fact; its not a matter of debate nor can I do anything to change it. Facts are like that. If you seriously think that what I stated my opinion then I advise you to study the theory and history of audio.

Now it is true that the majority of the audio industry has chosen to use the Voltage Paradigm. If you look at history you will see why- high efficiency speakers are more expensive to build. Just follow the money.
Atmosphere: "the simple fact is that any speaker that has high efficiency conforms to the Power Paradigm unless the designer went through extraordinary steps to prevent that"

This is fact:
My Current MTM's had a hugh power response hump about an octave above the crossover frequency to deal with. Power Paradigms are not as critical in all designs, but they always exist.... Always.
It seems the popularity and proliferation of low efficiency speakers can be traced to the advent of transistor amplifiers. Speaker builders were`nt compelled to take the time/skill required to design high quality high efficient speakers, instead you could just continue to make ever more powerful SS amps to compensate. The SS approach was muh cheaper than relying on tubes. Need 200,400 or 600 watts to drive a particular speaker? No problem, how about 1000 or 2000 watts(as with class D amps currently). The motivation in this direction was`nt purely in the direction for better sound or realistic reproduction of music as the objective.
Charles1dad:
"It seems the popularity and proliferation of low efficiency speakers can be traced to the advent of transistor amplifiers"

I didn't know the tracing of low efficiency speakers to be linked to solid state amplifiers. Could you please educate me on the evolution or tracing of such?

I am aware of basic speaker design and much of its evolution, I have never heard speaker design evolution linked specifically to solid state or tubed amps. I'm very interested to hear this. Thanks for your help.
Charles1dad, much of what you posted is correct, but, the perspective might be somewhat misconstrued. Yes, the advent of reliable, affordable high powered ss amplification more than 40 years ago, allowed more people to afford higher power amplification than was previously the case. It could also be argued that it permitted speaker designers greater freedom to design better speakers, than were previously viable, due to the previous constraints of the time.
Hi,
Unsound, Yes I believe you understand my point,With the delvelopment of solid state power amplifiers it became possible to offer to the marketplace much higer power for considerably less money. Tube amplifiers that could yield 150 watts or higher were far more costly circa 1960s-1970s. This provided the option to build low efficiency speakers as now there were alternatives to costly high power tube amps.

Whether these speakers were "better" or not is subjective, some were fine and others were`nt.(variable results for sure). My point is that speaker builders were no longer held to a restriction in regards to efficency limits, as the era of available SS power(transistor technology) made that concern moot. One could simply build and market ever more watts to meet the demand of increasingly power hungry speakers.
Thanks,
Unsound makes a great point. Thus we have speakers like Soundlab, Apogee, Martin Logan etc...
Along with bootlegging, the movie industry existed as one of the principle growth industries during the Great Depression. When sound came to movies, the need for sound projection was forced by the desire to sell more tickets in bigger houses. This resulted in hyper-efficient horn loudspeakers that could fill increasingly larger spaces with increasingly greater fidelity, even though the tube amplification of the day was limited to just a few watts. There was no stereo.

The greatest American speaker designer of all time, Harry Olson, created designs in those days which have never been exceeded.

The statement that more compact, less expensive speakers were developed for mass consumption is accurate. The comment about those speakers being superior is inaccurate. They did, however, sell better just as they were intended to do. They cost maybe $100 each and could be set up in small spaces. Their use would not have been possible were it not for solid state power. They provided difficult loads and demanded much more power than horns but the masses could afford to buy and house them. So they crept onto the scene.

Meanwhile, horns driven by these early solid state amplifiers were strident and coarse. Garbage in/garbage out!

Today, as we argue, we need to acknowledge that SS has come a very long way and that there are certainly dome tweet model speakers that
can play music very well. Not all horns are wonderful. However, when the discussion turns to ultimate superiority in the reproduction of a live musical event, when cost no object products are introduced, and when honesty overrides cloudy bias, horns prevail. Twas always thus.
Grannyring,
No ono`s denies that very good sounding inefficient speakers exist(certainly not me) just as there are very good high efficiency speakers. The mass market/mainstream production of early transistor amps was a major impetus for increasing the number of inefficient speaker being made. We both agreed in earlier post that there`re multiple routes of reaching one`s sonic fulfillment. You`re happy with 600watt amps driving the Sound Labs, I`m happy with 8 watts driving Coincidents. It`s a big boat with plenty of room for us all.
More like stereo killed off hi eff. Tossing in the new air suspension designs increasing power availability it wasn't sound quality but cost and size that did the big horns in. 1st stereo broad casts where 1 channel AM 1 FM those early adopters bought 2 systems to enjoy stereo. Homes where smaller then and housing 2 large horns became a problem for many. Like those who tossed there stereos for new HT in a box did they step up in music quality or down? Did those who moved to MP3 selling off there cds. Or those who sold off lp collections to move to digital. To me tech isn't necessarily about improving quality.
Speaker manufacturing has evolved. Technology has improved in the form of materials, software and the equipment that drivers are made from. All along, manufactures have done their best to produce a quality product. The solid state amp came to be commercially produced in the late 1950's is not what developed speaker technology. People wanting to build the best did. In the 1960's, raw parts manufacturers had a hard time maintaining 20% accuracy from part to part, in the 1970's we saw a huge improvement to more like 10%, today parts can be produced at under 5% deviations off manufacturing lines and better on hand made items. Magnet materials have improved, voice coil formers have improved, tighter tolerances for voice coil gaps have improved, flux has improved, linearity and excursion limits have improved, better materials for cones, horns and diaphrams. There have been changed in mylar materials in planers, there have been improvements in electrostatics, there has been improvements in damping on all levels... Speakers have evolved as technology has improved. The formula's for highly efficient speakers are the same today as they were in 1960, its just that today, we have much better tools and technology and materials to produce a more accurate product. That doesn't mean, nothing of old is good, accurate or even great, it just means that today, we can do it more consistantly.
So what is the best speaker then?

And what is it's efficiency?

And how big is it?

And how much does it cost?

Sorry,these things matter to me so the ability to fill an arena with sound best does not necessarily make it the best speaker for my application.

How about yours?
This thread is a troll post and nothing more, has zero merit for discussion. I imagine you suffer from aliteracy as you would have never posted such an ASSanine thread.
Acurus,
Rather than getting yourself so upset and others until you are called names, Why didn't you just click on another thread and ignore this one?
I completely agree that there has been alot of useless info passed, but in this thread some knowledge and experience has been passed that might help someone. There are a dozen or so of us trolls that posted on this thread with a wealth of knowledge and experience. As a whole, most were just trying to help.
Acurus - Don't criticize what you can't understand.
It would appear that spelling is not your greatest weakness.

Just stop and think about why it bothers you that other people are discussing a subject among themselves. Try with all your might to figure out what gnarly synapse in your cranial enterprise is offended. Then, if you master that challenge, try to determine why it bothers you so much that you choose to lash out at us for chatting about our respective beliefs.

It's not like we're standing in your front yard or anything.
Timlub and Unsound, back in the 1950s the tube was the only game in town. Its no mystery that tube power is expensive- by the late 1950s the most powerful amps for home use made only about 60 watts per channel.

Now it should not be a matter of proof (Unsound) but common knowledge that the closer tolerances used in high efficiency speakers results in greater reactivity (reverse EMF) from said driver. Timlub, I am including you in this post as the fact of the matter is that during the 1950s the higer efficiency speakers that existed out of necessity required greater precision to manufacture.

However with the advent of the transistor inexpensive amplifier power became available. There were two things that were direct results: 1) amplifier manufacturers realized they could make more money, as the transistor amps cost less to produce, 50% less or more, yet they could charge at least 90% of what they did for tube amps of the same power. 2) speaker manufacturers realized a similar benefit; by reducing precision they lost efficiency, but the cost of the drivers fell by 90%.

Its like I said, just follow the money. The advent of transistor amps and lower efficiency speakers was not about advancing the art (although the marketing certainly made it look that way) it was about *making money*.

Unsound, if you want proof that I did not make up this idea of the Power Paradigm, look for a Fisher 55-A amplifier. Here's the Google search:

http://www.google.com/search?hl=en&q=fisher+55-A+amplifier

Take a look at the fifth hit (but look at the other links too). Its a Youtube video, but in the photo provided by Google, you see a control. The control is marked 'constant voltage' at one extreme 'constant power' in the middle and 'constant current' at the other extreme. Constant power is a zero feedback state in a higher output impedance amplifier. If I made it up, how come Fisher put that term on an amplifier made the same year I was born? The simple fact is the idea existed 55 years ago, and was the state of most tube amps, and speakers had to be designed to work with them since they were the only game in town.

Such speakers like Altec, JBL, Klipsch and the like all have midrange and tweeter controls. Now most people *these days* think that those controls are there to allow the speaker to accommodate the room, but this is not true. The controls are there to accommodate the power response of the amplifier! Once you realize that fact, once I realized it, the reality of how things were done back then became more clear: it was the Power Paradigm.

This is why I recommended you look at the history of audio.
"Speaker manufacturing has evolved. Technology has improved in the form of materials, software and the equipment that drivers are made from. "

I'd say that is a fact.

It's why the rules that determine best solutions these days are not the same as 50 years ago. Its called PROGRESS!

Advantages that mattered 50 years ago may not matter so much today.

Not to say that good efficient speakers don't have advantages, but the advantages that mattered 50 years ago do not so much today.

The bar has been raised considerably over this time and a lot of it due to modern advances in technology that work extremely well together. Like modern speaker designs, Class D amps, digital, etc.

Not to say that vintage technologies like tubes, vinyl, tape etc. don't sound better than ever either.....

There are many ways to skin the cat.

So go ahead and buy the most efficient speakers and a matching flea powered amp as well. It may take a long time to tune to sound exactly the way you want, but when it does I am sure it will sound great.

But there will be plenty of competition out there as well.

That's what makes the world go round...
I by chance stumbled into an old style general store along the bike trail the other day and was thrilled to find that the owner specialized in refurbished Victrolas and had an assortment to listen to and purchase.

I asked to hear a couple of the best sounding ones.

What I heard was quite lovely. Various smaller boxes with a crank motor filled that sizable venue with some lovely music from that era that, though technically limited and flawed, had a mechanical tonality and presence all its own.

I want to own a working Victrola some day. Not likely to dump my power guzzling OHMs and Class D amps to drive them though...
Anybody know what the typical efficiency rating of a Victrola is?

It uses no electricity yet can fill a quite large room with quite lovely sound. Gotta be extremely efficient! This may be the ticket!

Not much bass or high end though in those old 78's!
Depends on the year, Mapman. Some of the later models were sold with electronics inside. I'm hauling one back from the mid-West in a few weeks. No electronics, just a moderately sized horn in the cabinet.

I think hi-eff drivers can give the best of both worlds. If I want "audiophile sound" I just stick my fingers in my ears.
Thanks folks. I guess I am not really the one getting all upset based on some responses. I posted my comment as the initial post was a troll and if anyone has done any research or has had personal experience on the efficiencies of speakers and the combinations of amplifiers it would be clear that there are many inefficient speakers that some would argue are "the best" and vice versa. Having spent a lot of time with both efficient and inefficient, as well as designing my own Efficient speakers, I am not sure I would be lobbing bombs about my experience, Macrojack.

Sorry to get everyone all excited. Let's carry on and forget about my comments.
Atmasphere, it was the last three paragraphs of the post addressed to Mapman on 6/29/11, that I was asking you to prove.
Atmosphere: "Its like I said, just follow the money. The advent of transistor amps and lower efficiency speakers was not about advancing the art (although the marketing certainly made it look that way) it was about *making money*"
Hi Ralph,
I really disagree that it was about making money. Or the way I feel that you portray it as "just making money". I have no arguement that they charged what they could for the technology they produced, I would do the same and I'm sure you do also. You know the manufacturing cost difference in a $1,000 retail amp and a $20,000 retail amp, it sure isn't $19,000. If it was only about the money and not advancing the art, why are there so many wonderful solid state pieces of equipment today?

Long ago among other lines, I sold Cerwin Vega. I have no idea if this statement is true, but Cerwin condented that they marketed the first Commercially available solid state amp in 1957.
Lastly, very sensitive speakers has realy never been difficult to produce. Great sounding Hi Eff speakers has. I believe my speaker technology schpeel to be completely accurate. There were certainly some great sounding old speakers, but today, our consistency is in another league.
Tim
Bottom line, is the sound has to reach certain SPL levels to meet the listener's need.

I suppose one way to look at it is that with very efficient speakers, the amplifier is asked to do less to achieve that goal. That opens up a whole different ballgame if you are an amplifier manufacturer in that the burden is lifted to some extent. So you might lower cost on the amp or focus on other quality aspects of the amp I suppose as desired, depending on your target market's needs.

Now, if the speakers are less efficient, there is more of the basic function of an amplifier to do to achieve the goal, ie the amp must amplify more. That changes the game accordingly as well, however my point is that I feel comfortable that modern and more mainstream innovations in amplifier technology, with all the economic advantages that go along with being more mainstream, are up to the task of retaining high quality and value in this game on par with the best out there.

I might not have felt quite the same way about this a few years ago before testing the waters with modern, high efficiency Class D amps that target the audiophile market, but my call at this point is that the efficiencies in modern amp design can offset whatever historical efficiencies may have existed for speaker designers.

I think amplification can be done well in many ways, either mechanically using horns or electronically using modern SS or even tube amps, chose your preference.

Not to say all makers of speakers or amps actually do it really well though. Some do it really well. Many do it pretty well. The rest do not survive or else find a different and less fussy target market.

That is a big difference!
Unsound,
Atmasphere wrote about Power and voltage Paradigms.
Here is his article:
http://www.atma-sphere.com/papers/paradigm_paper2.html
Power being the product of voltage and current, I must have one SLIGHT beef in terms.

Voltage Source....no problem (paradigm, if you insist)
Current Source....Instead of 'power'. (again, paradigm if you insist)

See the writings of Pass for further information...
Read this with the Atmo article::

http://www.passdiy.com/pdf/cs-amps-speakers.pdf
Hi Magfan, I am no amp designer, I have built alot of speakers. Recently I built a nice MTM. I ended up with an 4 ohm bottom and an 8 ohm top..... In speakers anyway, where you deal with impedance dips and peaks of up to 30 ohm or more, it is not unusual for a speaker even in a network of speakers to get hotter than the others when an amplifier (in power paradigms ss peaks power to certain loads. That is one of the few reasons that impedance compensation is used and often resonance compensation. In this current MTM, I drop to 3.8 ohms in the bass through the midrange while the tweeter has a peak up around 12 or 14 ohms. I had to place the crossover so that the crossover point was low enough to stay away from where the power hump would be in the response & impedance curves, otherwise you would have clearly dealt with fatigue above the crossover point because of the power paradigm. I am not experienced enough in amp to design to properly discuss power or voltage paradigms in amps. I hope this is adequate explanation(90 % accurate for explanation)to make since of a power paradigm in speakers.
Magfan, I have one slight beef also. If one were to take away the bias, one could often reverse the positions, and perhaps to better effect.
Unsound, is this the comment you want me to prove?:

Now the Power Paradigm offers that possibility of being that much closer to the music. The idea is that the technology is totally committed to the rules of human hearing, which I think all of us can agree is the foundation of audio; without our ears we would not play with audio gear at all.

OTOH the Voltage Paradigm is all about looking good on paper (IOW pays little attention to human hearing rules), which our ears could give a damn about.

So going to higher efficiency is clearly an access to transformation in sound quality. Of course its better!

The first paragraph seems to require little in the way of proof; I can guarantee that if we did not have ears we would not play with audio equipment. That part is simple enough.

Paragraph two is simply taking on the idea that the main issue of the Voltage Paradigm is that it produces good numbers without those numbers having much to do with hearing rules. The proof is one that I know you already have seem me expound on in the past: The Voltage Paradigm looks for constant voltage response out of the amp. Another part of its platform is distortion as low as possible. In 99 44/100ths of cases, this requires loop negative feedback in the amp.

Designers have known since the 1950s (see Norman Crowhurst- I'm not going to dig this up for you since it appears you need the history) that loop negative feedback increases odd ordered harmonic content. That violates the most important hearing rule- the one of how we detect sound pressure, which is done by listening and measuring the the amount of odd ordered harmonics. Obviously if these harmonics have been enhanced (distorted) even slightly, we can hear it and it will the difference between what we call 'good sound' and what we call music. The paragraph closes with the simple fact that our ears don't listen to numbers on paper. Your eyes are better suited to that task.

The closing paragraph simply points out that the higher efficiency drivers are better suited to Power Paradigm technology, which from the previous paragraphs we saw pays closer attention to the effects of distortion upon the ear. That is why I used the word 'access' and 'transformation' as when this approach is used the results are instantly audible to anyone- it takes no golden ear to hear.

Did we have the conversation about what Chaos Theory has to say about amplifiers with negative feedback?
Atmasphere, thank you for your thoughtful response. It's a bit late at night now, but I thought you deserved a speedy reply.

You have not offered any proof that: "Now the Power Paradigm offers the possibility of being that much closer to the music."
Or that: "OTOH the Voltage Paradigm is all about looking good on paper (IOW pays little attention to human hearing rules), which are ears could give a damn about."
or that: "So going to higher effciency is clearly an access to transformation in sound quality. Of course its better!"

I'm confident that some of us can quite easily hear some of the results of those measurements that you choose to discard. It would be just as easy (if not easier) to make a speaker with a lower impedance ( and hence probably less efficient, at least for amplifiers that might typically be classified as power paradigm amplifiers) to have a narrow impedance swing. In fact many such speakers already exist. The use or non use of negative feed back is not the exclusive province of any of the popular audio amplifiers technologies.

At exactly what levels do we find odd harmonic content objectionable? It has been suggested for example that some people prefer 3rd order harmonic distortions to 2nd order harmonic distortions. I would suggest to you that it's quite possible that some of the objectionable artifacts you describe could easily be swamped by other greater objectionable artifacts that the alternatives replace them with.
We might not listen with our eyes, but we can certainly put measurements in proper scale and use them to confirm and compare. Without such tools, we're only left with opinions.
What is efficient use for one tool, might be inefficient use for another tool. Though I'm not convinced that it's the most important consideration, so called less efficient speakers can and do comply with the power Paradigm. Fortunately, the amplifiers best suited for those speakers are also capable of adjusting when necessary, without stumbling to the inevitable peaks and valleys that real world speaker loads present.

You have previously posted here about Chaos Theory and amplification. With all due respect, a loose connection to a theory doesn't provide proof.

As always, I enjoy our conversations here, I've already begun to look at some of the items you've referenced. Thanks for the leads.
Un,
I'm not familiar with the rest of the conversation about Chaos......But will say that a proper theory allows predictions which can be verified.
The answer to this question will be based on your personal set of preferences. There is a clear differnce between SET's, higher power SS amps, horn and cone speakers.

Personally, I have rarely heard a higher output Class A/B, SS amp I could live with. The only exception is an amp I could'nt afford, the Dartzeel integrated. In general, I find the set of choices implicit in a higher powered design, produces a sound I dislike. I like tubes and SET's in particular. On the other hand, I have'nt found a Horn speaker I have enjoyed, which means I am not going to find a speaker with 100+ DB sensitivity.

My choices then, tend to be limited to conventional cone speakers of higher sensitivity, with higher output SET or other Class A Amp. I am willing to accept the loss of base extention you tend to find in cone speakers about 92 to 96DBs, as I am a classical, Singer Songwriter, Jazz kind of listener. So, I am using 96db sensitivity Daedalus DA_RMA's with both a 20watt Ayon Spark SET and 50watt Class A hybrid, Pathos Inpol. This combination is ideal for me, it won't be for others with different priorities. It also means there is'nt an ideal combination, just as others have mentioned, a particular set of compromises in Speaker and Amp design, that suits your needs. Vive La difference
Magfan, there are other posts, but IMHO this one might be the best example:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1264342155&read&keyw&atmasphere+chaos+theory&&st50
David12,
Very well expressed post, I imagine your system sounds very natural and emotionally involving. Enjoy!
Hi Unsound, thanks for the greater specificity.

You have not offered any proof that: "Now the Power Paradigm offers the possibility of being that much closer to the music."

Here's how that one works: The Voltage Paradigm places its highest regard on flat frequency response. This is as close as the VP gets to obeying hearing rules. Now what we are talking about is the idea that the amp can make constant voltage with respect to load- that gets you flat frequency response when the amp is used with a speaker that has box or driver resonance as part of its impedance curve (in a nutshell). What this *ignores* is the fact that the human ear hears non-clipping harmonic distortion as frequency response variation. In fact the ear is just as sensitive to this if not more so then *actual* frequency variation.

This is why two amps can measure identical bandwidth on the bench, but one can sound bright while the other does not- it has to do with distortion.

So if the amp is *required* to use loop negative feedback either in pursuit of a low output impedance so it can have a constant voltage characteristic, or in pursuit of low distortion (the other 'looks nice on paper' spec) the result is that the amp will sound brighter since the 5th, 7th and 9th harmonics will be distorted due to the feedback. It happens that the ear uses these harmonics to measure how loud a sound is. So distortion in this regard of slight, barely measurable amounts is audible due to the fact that this is one of the ear's most sensitive aspects: our **survival** might depend on it!!

IOW, the use of feedback violates a fundamental hearing rule- how we detect the volume of a sound. This is why I say that the VP is made to look good on paper, because it ignores this fundamental process of human hearing. Now if you can achieve low distortion and constant voltage without feedback, then you might have something. I know of only 2 amplifiers that can do that. I regard this as the cutting edge of technology and is the frontier where development can still yield results. If this obstacle can be overcome then I'm all for it.

The way the Power Paradigm works is that it acknowledges that reducing the distortion can be more audible than flat frequency response, and that certain distortions are more important in this matter than others. IOW, it is placing a greater value on the hearing rules than the Voltage Paradigm is. To this end, loop feedback is eschewed due to the facts I previously explained. To maintain frequency response due to interactions with the speaker, different crossover techniques are used. To reduce overall distortion, non-feedback methods are employed, although depending on the designer a greater or lesser emphasis may exist regarding the presence of the lower orders (2nd, 3rd and 4th, BTW the 3rd is the only odd ordered harmonic that the ear does not hear as harshness- it regards this harmonic as musical like the 2nd and 4th).

Personally I don't like the presence of the even ordered harmonics as they contribute to 'tubey sound' which I regard as a coloration (remember, the ear hears harmonic distortion as frequency response variation and this is an example). They can be eliminated by fully-balanced circuits.

Or that: "OTOH the Voltage Paradigm is all about looking good on paper (IOW pays little attention to human hearing rules), which are ears could give a damn about."

Now I did explain some of this already but in a nutshell the Power Paradigm holds as its highest ideal that the more the equipment is able to obey human hearing rules, the more its reproduction will sound like real music. The logic is obvious...

The Voltage Paradigm by comparison holds the value of flat frequency response and overall lowest distortion as its ideals, regardless of the fact that in doing so a fundamental hearing rule is abused. That is why I say it cares more for appearance than sound.

or that: "So going to higher efficiency is clearly an access to transformation in sound quality. Of course its better!"

I already commented in other posts- this is the one about higher efficiency drivers being more reactive. Amps with feedback don't react well to this- this is one reason why horns sound shrill and honky when used with amps that employ loop feedback (again, in a nutshell).

The point with this comment is that highly reactive drivers, if you want them to work right, are best used with an amplifier of little or no feedback. So the interaction between the amp and speaker is good, and the amp will not make the distortions that the ear finds to be the most objectionable (ideally- there are good and bad amps IMO regardless of what side of this debate they are on). That is the transformation- the access where the line between a good sounding stereo and a stereo that sounds like real music is crossed. IOW one has 'good' specs but the other is designed to obey human hearing rules. That difference is audible and is measurable too, once you know what to look for.

Two side notes:
1) all headphones are Power Paradigm technology.

2) Its important to point out that with a lot of traditional horn speakers, the crossover will not work very well with a modern transistor amp. The reason is that the crossover rules for a Power Paradigm speaker have different assumptions than those of a Voltage Paradigm speaker, based on the way the amp behaves. The result is that a horn running with a transistor amp will often be playing out-of-band information at volume levels that the designer did not have in mind at all!
Atmasphere,

I tend to agree with most of what you've said. In addition to these points I'll add that the distribution of the harmonic spectra is also important: their amplitutes should be inversely proportional to the order of the harmonic(ie. 3rd>4th>5th>...>Nth), in a more or less linear fashion. I don't for example like to see the 6th harmonic being highger than the 5th even though the even order 6th is the more "bening" one.

One of the best articles I've seen on HD perception (link bellow) is by Lynn Olson. For those not too technically inclined skip through to the middle where the heading is "The Sound of Different Harmonic Spectra". Also, for those believers in power cables there's a little bonus in the form of a technical explanation as to why power cables do indeed make a difference in many cases.

http://www.nutshellhifi.com/library/FindingCG.html
The best is whatever you prefer. There is no intellectual way to establish actual factual superiority without measurements and these forums generally decline that pathway when it is presented. This is an emotional experience that cannot be assessed and evaluated by cold, unfeeling machines.

So -- we pirouette endlessly basking in polysyllabics and wielding cliches and formulae to no end whatsoever.

I prefer the comfort afforded by stable and manageable impedance and high efficiency. It allows for easier amplifier matching and vastly broadens the number of amplifier options I can consider. Likewise, it reduces the amount I have to spend to purchase the horsepower necessary to drive my speakers.

But don't get me wrong. I haven't forgotten the other option. I remember all too well how I could have a big name speaker which sometimes drops to 1 ohm impedance and requires 600 watts of Class A power to move it's constricting and elaborate passive crossover network. Naturally I give that option the exact amount of consideration it deserves every time I consider changing my system.

So far, I have not seen fit to return to a choke box. Maybe I'll have a panel speaker again someday but it seems unlikely to happen as of now.

Nonetheless, tastes change --- even if practicality and common sense do not.
Macrojack, plenty of good 400-600 watt SS amps available from $1500 - $5000 new and used. I paid $1500 for mine. No need for all Class A power either.

I like the comfort and ease of no tubes in my power amps plus the fact that they can stay on 24/7 and always sound their best. My SS amp never even gets warm - always running cool.

My panel speakers are really a one driver - point source (Soundlab) speaker that uses one capacitor, one inductor and one resistor in the crossover (slightly modified by me). Sure they also have transformers also, but so do your tube amps.

Seems like a pretty simple, practical and common sense system option for many.
Okay! I'm not using tubes either although I have a pair of tubed monos stashed. The topic really is speaker efficiency and whatever advantages it provides.
Macrojack, I agree and I just gave a different opinion to your wise crack remarks about what others deem to be perfectly reasonable and rationally put together systems. Just wanted the reader to have a fair and balanced read :-)
Please don't use the phrase "fair and balanced" if you want to be taken seriously. I have been conditioned to expect partisan lies to follow whenever I see or hear that slogan. Southern accent is another flag.
I will always hope for fair and balanced - always! May not get their perfectly, but I and we can attempt to do our best. Sorry for your past experience with that phase and motivation, however it is a genuine hope of mine.
Don't know about anybody else but I found this conversation simulating and educational. It visited interesting territory, territory a rigidly specific destination would never have found.