We should reject hard-to-drive speakers more often

So far nothing perfect has ever been found by humans in this Universe and from my understanding of physics if it did exist all molecules in our universe would be equally distributed thus we wouldn't exist. It's all variables and compromises in any human endeavor these perfect loudspeakers could never exist since perfection itself doesn't exist. As far as rejecting lower eff that's more of a taste and experience or bias issue hi- eff low- eff most can have a good system built around them if you embrace strengths and mitigate known issues. If one wants dynamics, large image size, great transient response, and the ability to run off lower power but can accept a bit of size, different appearance from audiophile standards and can handle the limited market options or you can DIY, Hi Eff would be the logical choice. If you want what almost all audiophiles use and approve of, like to have many easy-to-source options, enjoy large power or need a small speaker. Low-Eff may be the best choice for you. There are still loudspeakers that are neither low or high eff those also may be worth checking out if you feel you want a bit of both worlds.

@atmasphere  - I'm trying hard not to use absolutes.  I'm sure your amps do fine!

Rather, I think ESL's bring a lot of other qualities to the listening experience which makes us swant to overlook the hard to drive aspect.

We buy ESL's in spite of the low impedance, not because of it.

High power class D amps more than make up for the difference in dynamic contrast between low and high efficiency speakers. High efficiency speakers have way worse problems than thermal compression.

@jon_5912 Rather than innuendo, could you be specific about ’way worse problems’?

If any amplifier is properly designed and operating properly, it will not add dynamic contrast to the signal. The signal itself is the source of dynamic contrast. Loudspeakers only take away from that; if you value dynamic contrast, using a speaker that has the least thermal compression will bring you closer to your goal. In this light, ESLs have the least thermal compression owing to no voice coil at all; a close runner up is higher efficiency loudspeakers, in particular those that employ field coils (since the magnetic field in an electro-magnetic loudspeaker does not sag when current is applied to the voice coil).

Some argue that SETs are the most ’dynamic’ of all amplifiers, but if you use a sound level pressure meter you find out that isn’t true- its really distortion on the leading edge of transients interacting with the way the ear perceives loudness that causes this impression.

Amplifiers cannot ’make up the difference’ in terms of dynamic contrast.

My experience with ESL’s says that this low impedance (1/3rd of an Ohm) in the upper octave is quite noticeable and often pushes owners to beefier solid state amps.

@erik_squires FWIW, about 90% of our MA-2 (a 220Watt class A triode OTL) production are running on Sound Lab ESLs. Tubes work quite well with ESL57s, ESL63s and ESL98s. Most solid state amps behave as a voltage source and since ESLs in general tend to have an impedance curve that varies by about 9:1 or 10:1 from the bass region to the highs, quite often a voltage source will sound bright as the amp doubles its output again and again as frequency is increased.

For this reason, some ESL producers make their speakers low impedance in the bass and nearly a dead short in the highs, limiting the ability of the amp to drive the higher frequencies (partly due to the speaker cable impedance becoming a significant portion of the source impedance).

Even then, brightness is an ever-present danger with such amps, particularly if they have distortion rising with frequency.

I think the answer to that is the so-called Hoffman’s Iron Law

@lanx0003 Exactly!

@atmasphere  what about large multi-driver full range speakers that are really hard to drive? They don’t get the Murphy that a smaller speaker does for low efficiency.

Thx for the comment.  You got me to think a bit while longer but it is definitely worthwhile. I think the answer to that is the so-called Hoffman’s Iron Law that someone more knowledgeable has pointed out. It states that the speaker designer could pick two parameters out of the bass extension, sensitivity, or small cabinet size in any given design, but in doing so it will compromise the third.

So extending that notion to your question, you can have efficient larger floorstander containing multiple, larger drivers in combination with cabinet designs to give great bass, small speakers with great bass and low sensitivity that I have craved for, or small highly sensitive speakers that can’t reproduce bass well.

yes low impedance in upper registers is nothing to worry about but tuning impedance curve in the lower registers to design a speakers desired characteristic.

My experience with ESL's says that this low impedance (1/3rd of an Ohm) in the upper octave is quite noticeable and often pushes owners to beefier solid state amps.

“I’d also like to point out that there’s a sub-thread here about high efficiency speakers which is not mine, I take no responsibility for those statements regarding efficiency vs. sound quality.”

@erik_squires  With your post headline I’m not sure how you would expect anything else here on Audiogon. We’re a subjective bunch, often ignoring objective facts about “why we should reject hard to drive speakers more often “

Perhaps “bragging rights” with cost or watts?

Nothing is more disappointing than too spend a small fortune on “hard to drive speakers” and mega watt amps only to come away disappointed or longing for something that seems missing.

So getting back to my point (or highjacking). Personally, trying to use and/or enjoy “hard to drive speakers” repeatedly has been a

“The Emporers new clothes”  thing.

My point was, there is no ONE speaker for all of us, let alone a perfect one. 

WRONG. Of course there is a perfect one. Why shouldn't there be? The perfect speaker is by definition one that satisfies all of us. We must stop creating imperfect speakers and start aiming for perfection. Also perfect speakers require perfect audiophiles. Some audiophiles dont WANT perfection. That is a completely different issue. I am one of the finest tuners in the industry. I have never met anybody who is as obsessed.

@bdp24 I have no idea what was said by kenjit, as I pass him over when reading. My point was, there is no ONE speaker for all of us, let alone a perfect one. Sorry if I was vague in my communication of that point. 

Geez @mrdecibel, my post above (or at least it’s last sentence) WAS offered in the spirit of lightening up. Too subtle?

I can't believe I am asking this question: Do you actually take @kenjit seriously?!

@atmasphere thank you, speakers designers can flatten out higher impedance in 4 Ohm speakers not sure how I got it mixed up.

@bdp24.... What if a few of us got together to try to design a speaker, we all liked.......This is the thing, and it is ok. We each like what we like, without need to defend why. Unfortunately, many are still searching for that " perfect sound forever ". And Eric, I meant zero offense. We all just need to lighten up a little. My best, always, MrD..

Fortunately for we humans, distortion of lower frequencies isn’t as audible/objectionable to our ear/brain mechanism as is distortion of higher frequencies. Right, Ralph? Since the beginning of hi-fi and continuing to this day, woofers commonly produce 10% (and higher) harmonic distortion. If a tweeter produced that much distortion it would be unlistenable.

If only @kenjit would put into production one of his perfect loudspeaker designs. The selfish sob is keeping them all to himself.

yes low impedance in upper registers is nothing to worry about but tuning impedance curve in the lower registers to design a speakers desired characteristic. I am thinking Wilson speakers would be a good example some Wilson’s are known for having great slam in the lower registers, does this make sense or am I completely off base here?

@jeffrey75 I don’t think Wilson is doing what you’re suggesting, if that’s what you mean by ’off base’.

Take ATC speaker/driver as an example, if one desires a good low frequency extension out of a small-to-medium sealed enclosure (which I prefer) design speaker with a given size of driver, efficiency has to be sacrificed.

@lanx0003 While this is certainly true, what about large multi-driver full range speakers that are really hard to drive? They don’t get the Murphy that a smaller speaker does for low efficiency.

I might see this a bit differently because our ears hear on a logarithmic curve. I figure if 100 Watts won’t do the job, 200 or 400 Watts won’t either because 2 or 4x more power isn’t that much louder- 3 or 6dB. To get to a perceived ’twice as loud’ its generally accepted that you need 10x more power. In radio parlance this is known as ’gold plated deciBels’; 1000Watts, I think we can all agree, simply isn’t practical.

In the opening, the OP said out loud that "We need to reject hard-to-drive speakers as being Hi-Fi". Now the tone was evolved to "... It's fine with me if you buy a car that gets 10 MPG. What I disagree with is the awe and bragging rights associated with that..." and followed by "No, your car is not better to ride in or more exclusive than high MPG Cars just because it's low MPG."

In reality, in the hi-fi world, I think very few audiophiles (if there is any) will procure speakers just because it's low efficiency. The speaker designed to have lower efficiency has its good reason. Take ATC speaker/driver as an example, if one desires a good low frequency extension out of a small-to-medium sealed enclosure (which I prefer) design speaker with a given size of driver, efficiency has to be sacrificed. Manufactures/designers could achieve higher efficiency by utilizing vented enclosure like tube/flat ports, lighter material for moving parts, horns, etc., but the sound reproduced from those designs may not suit some audiophiles' taste. In addition, quoted from the ATC designer, "The low mass parts are often not suited to the forces and resonances generated when reproducing audio at high SPLs and the structures that behave well at low levels can become unstable.  When the driver was reinforced for its stability and high internal damping, reduced sensitivity is unfortunately a trade-off.

I still say it’s just different human perceptions of what sounds good

I had some 3-way tower speakers that were supposed to be the bees knees- scan speak drivers with Ber. tweets) at around 87db sensitivity (translation more like 84 db) 

Same thing, comments on how “smooth” or “even” they sounded…

Every time I tried to turn them up loud for a more live concert experience (rarely), they always seemed to fart out (probably the thermal compression mentioned)

Im talking loud as hell here (balls out) for just a song or two.

My floor to ceiling line arrays do seem to get there db wise, but still sound smoothed to hell in terms of dynamics

Only thing I really like about em is their uniform loudness wether listening close or far (they don’t blow your head off up close, or fade way off if far away…)

As always.…YMMV

If we are to reject hard to drive speakers then we must reject the SNR1 immediately as they are horribly hard to drive with all the terrible components in the passive crossover. Get that dreadful thing out of there and go active Nigel I implore you!

Let me try to use a better metaphor.

It's fine with me if you buy a car that gets 10 MPG.

What I disagree with is the awe and bragging rights associated with that. No, your car is not better to ride in or more exclusive than high MPG Cars just because it's low MPG.

Also, if you lie about your MPG you should be held accountable.

That's my complaint about hard to drive cars.  I personally have no stake in high vs. low efficiency.  It's the reviewers and machismo that says "Oh, look, my car needs to have 99 Octane fuel to run therefore it's a real sportscar!" that needs to die. 

@jon_5912 wrote:

High power class D amps more than make up for the difference in dynamic contrast between low and high efficiency speakers. 

And how do they make up for that? There's only so much heat that can be dissipated in a given voice coil, not least a smaller one through typical low sensitivity. Power is power, and the less efficient receiver, unless extremely capable in power handling (which could have other, potentially detrimental effects), always ends up storing more heat, with all that entails. Thermal compression as in actually overheating the VC and causing heavy compression or sending the VC up in smoke is hardly the only, if even the main consequence following here, but rather what happens way earlier as something that has actual, audible effect. The degree to which this is pronounced, and at the (early) juncture this occurs and starts becoming a problem (referencing not least to a higher eff. scenario in which it isn't) would seem to be the more important aspect to investigate here. 

High efficiency speakers have way worse problems than thermal compression. 

I don't see how they do when properly implemented. 

Class D has high power and no audible distortion.  Amplifier distortion is no longer a factor.  High power class D amps more than make up for the difference in dynamic contrast between low and high efficiency speakers.  High efficiency speakers have way worse problems than thermal compression.  

Live music needs efficient speakers to reach suitable SPL levels but for smaller spaces speaker designers can flatten the curve but the impedance does go down.

@jeffrey75 If the amplifier is behaving as a voltage source and the speaker is designed for that (and 99% are) then a flat impedance curve isn’t important, and if you look at the impedance curves of many speakers, you’ll see that most speaker designers don’t value a flat impedance curve.

Class D is going to make high sensitivity speakers obsolete.

@jon_5912 As a manufacturer of class D amplifiers I can tell you this statement isn’t correct. The advantage of higher sensitivity combined with higher impedance will always result in lower distortion from the amplifier and the speaker will have greater dynamic contrast owing to less thermal compression in the drivers, plus the speaker will be less critical of speaker cables.

Until those three problems are solved easier to drive speakers will have an advantage.

I am not sure if I need to tell you it doesn't make sense.

See above.

Why?  Choosing speakers to buy / avoid based on efficiency is like choosing a new car based on a sole factor such as weight or acceleration.  I am not sure if I need to tell you it doesn't make sense.  ATC drivers/speakers are one of the most inefficient speakers (around 85dB/w/m) but, with due amplification, I am pretty sure that I do not need to tell you how good they are.

Class D is going to make high sensitivity speakers obsolete.  Amplification is a solved problem and the only thing left is to make it cheaper.  The high end audio world has to a decent degree accepted that the Benchmark amp is essentially perfect.  Some people want a particular flavor and that's fine, they can buy what they like.  For those of us who want a straight wire with gain, class D is there.  It's taken decades but there are now a bunch of class D amps that measure about as well as the Benchmark.  And some of them are very powerful.  The Hypex NCx500 module measures about as well as the Benchmark and is starting to show up in finished designs.  

This topic deserves 🙄

Late to the party, but I’ll never understand why folks don’t put systems together as a system and not just parts. Seems like folks just run to the net any buy used thinking it will all play well together. So many great products for all to enjoy, but not if they don’t play well together in the sandbox. Jmho. Not always about hard to drive, but I can say for my ears I usually gravitate to speakers that are easy to drive for most amps. 

I guess I missed the point of this statement,

Yes you completely missed the nuance I meant this with, and explained in depth later, and instead applied your own meaning to those words.  Try reading the next three sentences also.  It seems you are conflating my words with those of others who are making other, related points, which I am most certainly not.

Further, I really appreciate the camaraderie you have shown me by immediately suggesting I don’t belong here and should be at ASR, regardless of how you interpreted my statement. That was really elegant and I’ll absolutely attempt to emulate your behavior when I interact with others going forward.

We need to reject hard-to-drive speakers as being Hi-Fi.

I guess I missed the point of this statement, and yes I have read many that is why I mentioned amirm.

saying a 16 ohm speaker design is better than 4 Ohm speaker design strikes me as hyperbole.

@jeffrey75  Since I've never said or alluded to anything like that statement I don't feel obligated to defend it either.  I encourage you to read all of my posts, in addition to my original on this thread.

So Erik when did you start drinking your wine with amirm at Audio Science Review, specs are important but saying a 16 ohm speaker design is better than 4 Ohm speaker design strikes me as hyperbole.

It was more specifically the Crown Studio Reference. It was awesome, back them. I have not heard a GAN amp in my system yet. I have tried other class D, none which did anything new I do not have with my current collection of amps. As I enjoy class A, and I enjoy mosfets, I am sure there will be one coming my way ( Ralph, are you listening ? ). I am behind Wolf in the line....MrD.

Buddy of mine a long time ago owned the TOTL ( at that time ) MBL. He was running them with the TOTL ( at that time ) Jadis gear. Vinyl and cd were used. The system sounded remarkable, as far as tone and spatial properties were concerned. One day, I brought over my Crown Reference ( whatever the " audiophile " home version was at the time, as I no longer own it ). Talk about dynamics and control. MBL / Crown were a match made in heaven. IMO, for what I wanted, that pairing was dabomb. Owning Lascalas at that time as well, my buddie’s system, with the Crown ( fully balanced, 2 20 amp dedicated circuits ), was a revelation. I played my vinyl of Santana’s Amigos album, and when Europa came on, I cried like a baby. Knowing the story behind the song, written by Carlos and Tom, it has always been a deep deep listen for me....but.........I never had that same reaction using my Lascalas, or anything else for that matter. I might say, it was the BEST listening experience I ever had, listening to a system. I give the credit to the MBLs. So, they needed power. I sure did not care. Phenomenal ! Another point. My analog rig did not equal his, and digital did not equal analog ( back then ).My best, always. MrD.

Speaker designers are driven by their education, experience, practice, and their personal sense of hearing, and they're sometimes also biased by what they or their marketing partners believe is consumer preference at a certain price point. How each speaker designer arrives at his product goal creates a whole variety of synergies, dependencies, and sound profiles. None of those resulting designs are wrong or hard to drive unless the home audio consumer market stays away from the product or the reviewers kill it.

Basically today, there is so much speaker choice in the marketplace at literally all price points that something perceptibly hard to drive is essentially a side issue because there are always identically excellent choices that are ideally suited to someone's existing amplification and room and physical cabinet size preferences. 

Suggesting that "hard to drive" is a no-no implies that development decisions by speaker designers should be limited. I think that's counter-productive. 

I drive my W/P5.1 with Pioneer M-22 2×30 Watt A-Class, sounds amazing.

@ bigkidz +1

The theory doesn't always hold true.

Having recently place the Vandersteen Sevens in our Listening Room.  83.5db.  Never would have thought to pair them up with a SET 28wpc stereo amp but there you go, drove the hell out of them.  So you need to try things in order to find what will work in your system.

Happy Listening.

That does indeed read like a good bet Ralph.  

Don't know how to explain it; driving our North Creek crossovered B&W Matrix 801 S2 speakers (87dB sensitivity, nominal 6 Ohm with benign phase angles and amplitudes) with only our 100 watt monoblocks (2x6BL7 + 4xKT77) sounds both better...and louder!...than driving the woofers with a Jon Soderberg modified Threshold Stasis 2 (~225 watt/ch.) and the tube amps driving the midrange and tweeters. 

I chalk it up to coherence tricking my brain into thinking it's louder...are there decibel meter apps for smart phones?  No need for responses to that...Google here I come.

That a speaker is difficult to drive just means you need to get gear capable of driving it. I think the great majority of people who own such speakers have got suitable power for them. 

Of course that is very true. But like I mentioned earlier, if it were a simple thing to have the speaker be the same but otherwise higher impedance/easier to drive, it would be instantly smoother and more detailed both at the same time since the amplifier would be lower distortion.

This is audible; Steve McCormick makes a very competent solid state amplifier that can easily double power into 4 Ohms as opposed to 8 Ohms. The Anticables guy makes a device called the ZERO that is an autoformer that allows you to drive a 4 Ohm load while the amp sees an 8 Ohm load. He has a letter from Steve that states while Steve's amp can easily drive 4 Ohms, it sounds better driving the same load through the autoformer. I'm sure the autoformer has losses and the like; its pretty good bet that if it were not needed the result would be even better.

@atmasphere  The question for me is not whether the sensitivity of one's speakers matters in terms of integrating them into a system. Obviously it does. Nothing you are saying is new to me. The question is whether low sensitivity speakers are bad and they should be avoided. I think that's silly.  That is just a silly as if I said from my experience the high sensitivity is bad. That a speaker is difficult to drive just means you need to get gear capable of driving it. I think the great majority of people who own such speakers have got suitable power for them. 

Yes, the 705s are not that hard to drive. But whether the speakers were sensitive or not was not the issue. Did I like the sound? I know two people who have Maggie's and 400 watts in each monoblock to drive them. They love them.  I see no reason to consider the fact that a speaker is hard to drive as a negative in and of itself. If you don't have or can't afford the power to drive them, then sure, it's a factor. 

@brev 

This is why it makes a difference: the harder you push the amp, the more difficult the load, the more distortion the amp will make. The other thing to consider is that not all really high powered amps are all that musical- its pretty well known that smaller amps tend to sound better.

I suspect you're using the same amp since both the speakers you mentioned are fairly easy to drive. But consider that if 100 Watts won't do it, you'd need 4 to 8x more power to do the job and as you point out, that can be expensive.

Also keep in mind that while the ZU is easy to drive, its not the only speaker that is meant to be easy to drive and there a number that IMO are also better sounding (while also being more efficient).

@atmasphere  Yes, the 705s are not that hard to drive. But whether the speakers were sensitive or not was not the issue. Did I like the sound? I know two people who have Maggie's and 400 watts in each monoblock to drive them. They love them.  I see no reason to consider the fact that a speaker is hard to drive as a negative in and of itself. If you don't have or can't afford the power to drive them, then sure, it's a factor. 

@erik_squires I encourage you to read about Hoffman's Iron Law. Can't have your cake and eat it too. ;-) 

https://www.salksound.com/blogtopic.php?id=3

If this were the case about Loudspeakers not the most efficient like  Truly Great speakers like the MBL 111. Omni directional speakers would be ignored , or the Excellent Apogee ribbon speakers from our great audio past , or Maggi Magnetic 🧲 planer speakers .if you have the extra watts  they like and a bit of extra room , they provide very life like reproduction 

of music ,their longevity in Audio is a testament to their popularity with other Audiophiles, myself also  owns Dynaudio speakers That are 86 db efficient ,they sound very good but they too like a few watts to. Bring  them front and center 

we are talking literally a few extra watts to bring out all the low level details , to me a small sacrifice .why don’t Erik state what exactly his Audio system is made up of 

so maybe he can point out what we maybe missing  !!

@brev I get that this was your experience which I don't argue. But the sensitivity of the speaker does matter. FWIW, if you have the standmount version of the 702, its a pretty easy speaker to drive despite being a little less sensitive.

I just returned a pair of zu audio dirty weekend speakers. Very sensitive speakers.  Tried a pair used Bowers and Wilkins 705s. The original version. Much less sensitive. To my ears, more natural and clear. I don't think sensitivity is an issue at all. Just whether I like the sound.

I always wonder that too. I think the original reasons were that the loudspeakers were cheaper and so were the higher powered solid-state amplifiers. But that’s not really true anymore.

Also for cone speakers (generally) just shrink the voice coil and widen the gap and “bingo” you’ve got a much flatter frequency response (and usually less expensive manufacturing cost)

I have tried multiples of pairs of rather low sensitivity loudspeakers.

Dozens of them…not 100’s though (likely BS on anyone having tried 1000’s of pairs lol)

They always leave me dry, but many of friends and family seem to enjoy them so again it’s all subjective.

I’ve got  both types of systems now (one in the basement another in outer building)

For the low sensitivity system I’ll get compliments on how “smooth” or “nice” they sound.
To me I’ve come to take these adjectives as code words for “flat”, un-exciting or “not dynamic”

But it’s the never ending story, and taste can’t be argued.