Are high efficiency speakers necessary? 

Awesome! will do! thanks again!

There’s yet another compromise: the greater the speaker driver’s excursion, the higher the distortion. It’s actually a linear relationship. As one goes up, so does the other. Therefore, as the volume gets higher and the cone moves further to produce that volume, the distortion goes up, too. However, with a very sensitive speaker, the driver cone moves much less while producing the same volume, and producing much less distortion. It will also be able to resolve lower level details in the music better. You can make the cabinet bigger, which increases sensitivity by reducing the effect the air in the cabinet has on the back of the driver, or you could add a horn to the front of the driver. The horn functions as an acoustic amplifier, by letting the driver couple better with the air in the room. You could compare the effect of adding a horn to the difference between swimming barefoot and swimming with swim fins on. When you’re barefoot, lots of energy is used, but not much forward motion is produced, because your feet can’t get a good grip on the water. When you add fins to your feet, now you can swim at higher speeds with half the effort, and can easily swim much further before you get tired. A horn does something similar to a speaker cone: now the cone barely moves, which really reduces the distortion, but the maximum volume it can produce goes up, while using a fraction of the power needed by the low-sensitivity speaker.

Horses for courses

Klipsch are garbage if you actually like to listen to music. Their "horn" design may be highly efficient, but you might as well listen to music through a traffic cone if you think Klipsch has high sound quality. Cover your mouth with you hands and sing your favorite song and that's what a Klipsch sounds like. I'm guessing that Klipsch left a lasting impression with their advertising, back in the 70's, so people recognize the name and associate it with, "high end". Listen to a pair of Tannoy's and you'll realize what you've been missing.

@@scooterpickle8625 I got tannoys revolution xt8f and they are quite similar to klipsch in overall feeling. Bass is quite strong but there is more midrange than heighs in tannoys compared to klipsch.

Q varies along with efficiency which changes box /enclosure requirements. You covered that already. Something you might have overlooked is the distortion. High efficiency motor requires lower current which ultimately leads to lesser flux and inductance modulation for same SPL output, hence lower distortion.

AcousticTheory while paper woofers reinforced wth special resins, glues do have good strength to weight ratio. There are many other materials with better strength to weight ratio. Low mass stiff carbon fiber woofers have a much greater strength to weight ratio than paper woofers. That is a scientifically proven fact. And they are only getting better and better. The new TeXtreme ultra thin ultra stiff ultra low mass carbon fiber woofers enable woofers, mids and tweeters to perform much better performance wise than normal woofers, mids and silk dome tweeters. With much lower distortion and cleaner more detailed sound. And better break up frequency.

@@C--A of course carbon fiber has much higher stiffness to weight ratio but what about internal damping?? A stiffer membrane will have a much worse breakup mode though at higher frequency. So, eventually everything depends on designed bandwidth of the driver and implementation. A paper cone might perform much better than a carbonfiber one in some cases. It would be inappropriate to generalize the end results.

Chinda Ajoku TeXtreme diaphragms’ main benefit is reduced section thickness by using wide, flat fiber tapes. A carbon fiber cone needs to consist of the fiber weave (many tapes woven together), resin impregnation of the tapes, and a drip coat that creates the final air seal. When you can make a woofer with large diameter relative to the section thickness of the cone, then conventional woven carbon fiber (not TeXtreme) can compete with paper for strength/weight, but with conventional carbon fiber a great deal of the mass of the diaphragm is its resin content, so smaller cones with the same section thickness and same carbon fiber weave construction do not achieve the same strength to weight ratio as paper because the paper diaphragm can be made thinner with less resin content. That’s where TeXtreme comes in, but the only applications where TeXtreme has been commercialized are those where the relatively high price of the branded TeXtreme material does not increase the price of the end item unacceptably. So we see it only in very high-end cone/dome drivers (like the SB Acoustics product) and in the Eminence compression driver. (Also, RCF and Community have used woven carbon fiber diaphragms for compression drivers in the past.) I would also like to see TeXtreme used for some high end pro audio mid bass drivers from companies like 18 Sound, B&C, or RCF, but that’s viable only because their drivers occupy the high end of offerings, otherwise the price and processing of TeXtreme would be a major issue.

Glad you said it, now I don't have to!

Yup. LF extension, sensitivity, economy of size: pick 2.

+Michael Lee "The key thing to remember is that once a driver is made, you cannot put it into a bigger box to make it more efficient." A lot of drivers don't even have specified enclosure recommendations. With most off-the shelf cheaper drivers, if you have a bigger box, surely the bass will be louder even if med and treble is not. With a bigger box, you need to tune the vent to match the driver/enclosure setup. With a larger box you don't need such big chokes on the woofer that you would need with small boxes (a big factor causing small enclosure inefficiency). With less chokage and a bigger box wouldn't it be more efficient (at least in the bass)? You may get too much bass for the tweeter used, though and it may sound "muffly". Just get a more sensitive tweeter and you then would have more efficiency all round. Bullet tweeters!

Also distortion comes into the equation. You can get lower and smaller with more distortion too, although obviously no one wants that. So I think we have to assume the standard tradeoff puts distortion above all else and forces all compromise on the other factors. Am I wrong on this? I thought/think distortion was also dependent on these other factors.

Depends on the designer, this applies for FLH and related applications.

I have a pair for sale. I am the original owner of a pair of Altec Valencias from the 60's.

You’re right that musical instrument speakers often are not neutral sounding. That doesn’t matter to many musicians, because that speaker is a sound producer, not a sound reproducer. As long as it makes sounds that the musician likes, it’s a good speaker. Many musicians want to create a sound that’s immediately identifiable as being produced by them. Think of Carlos Santana, Mark Knopfler, or Stevie Ray Vaughan. That’s why some guitarists went as far as poking holes in the amplifier’s speaker cones: to get a different sound. Nowadays, you can pretty much dial in the sound you want, but everyone still wants to sound different, unless they’re playing in a tribute band.

Everything sounds amazing, until your hear something amazing

@@mikevincent6332 LOL thats so true. Ignorance is bliss. I went from loving my system to counting down the days for upgrade

I see.

shaun agreed with shaun build ya own but research every book and online thing youbcan plus read most of the loudspeakwr cookbook

I have done this before the Internet . The books tell /you how they build there own . All speakers very from the next . advice from others can lead you off . I always prefer 2 way .

Yeah, its fun, but you quickly realize that, unlike building amps and preamps, you need a lot very expensive equipment to rival ready-made or ready-to-build kit multi-driver speakers. You can make a convincing speaker pair using full range drivers as they typically use no or very simple crossovers, but traditional 2 or 3+ way speakers become more a proof of principle project than speakers you will live with for a long time.

+shaun When they make the formulae, it's only an "average" driver characteristic (which like doesn't exist) the drivers are always a bit different. Formulae only really work if they are for an exact certain driver (brand and model) as long as you use that exact same driver and proper cabinet specs. Otherwise you have to listen and change the crossover to make it sound better (after first following the formula) that's if the formula is just a basic general design (not for specific drivers). Lets start with a med choke example, cos it's hardest and you can get the idea and apply it to other parts of the crossover. And remember the crossover makes the speaker sound any way you want, it's just a nightmare doing it, that's all. Anyway here we go...If it says in the formula (for example) to use a .8 mh choke resisted by 15 ohms (for the med or secondary woofer choke) do it but don't solder the crossover (use alligator clips) and listen first. Use one or two "pet' albums that you know that is the "right" overall mix. Don't use different albums, you will be getting nowhere (just stick to a couple of "pet" albums). And use a good FM radio station as well for variation of songs. (Same example) Leave the choke in for a week (or as long as you can tell what's wrong) and after a few days it will hit you like a to of bricks. If the bass/med/treble mix is wrong you will know after that time (that's for sure) and it will be obvious (but not straight away, only after some time). And how much time will depend on how severe the mix is wrong. (Same example) If med is mostly too strong and sounds too high, simply go to the next choke size up (1mh) and so-on. Or if the med is too weak and too deep, simply go to the next choke size down (.68 mh) and so-on. In both cases the difference would not only effects depth of voice notes but voice intensity as well (and tending to be doing it the right way) and so usually not having to change the resistor. But if the med is just more (or less) intense than it should (no need to change the choke) just change the resistor (like how I described with the choke). And another thing, budget HIFI speaker manufacturers don't go fine enough increments especially when it comes to woofer/tweeter balance. Changing it by resisting one or the other just a little bit (like .47 of an ohm each way) can make the difference between a "husky" voice or a "boxed-in" voice. And always try to judge if the voice is "in-the-box" or "out-of-the-box". When the voice is "husky" it's "out-of-the-box" but sounds shit. The middle stand (so voice not "husky" or "boxy") is a real "knife edge" and that's why I say woofers and tweeters can NEVER be magically perfectly matched just connected straight up (even if one only needs .47 ohms).

terrywho22 Most people can't do this without equipment and a sound proof room. But I do it and I have 2 great pairs and I am making more (as a hobby). I started 5 years ago and practiced all that time to make crossovers just by hearing it. No formulae, no equipment, just a room and my ears. I can make a crossover that sounds great in a hour, now (and another week to fine tune it). It takes nearly that long to find faults after building the crossover... until suddenly it becomes obvious (but hardly ever straight away). Unless of course it's way, way out. But in this case I'm talking about fine tuning with really tiny increments. I do it cos I am a point source speaker nut (like the KEF uni Q). If my speakers weren't point source I wouldn't do it. I buy selected drivers from eBay and I match two ways so the tweeter fits inside the voice coil cavity of bass/med drivers. I have two sets of speakers working so far and are the best speakers I've heard. Simply cos they are point source and phased aligned. I line the diaphragm of the weeter to be just above where the "woofer" cone meets the voice coil tube. I use PA type bass/med drivers (not woofers) cos the bass/meds have thinner cones for better med than (cheap) woofers and (on some) the voice coil is large enough to insert a tweeter inside. But with woofers it is not possible cos the voice coils are too small diam. My First point source set of speakers cost about $600 to build and are 10" PA speakers with a 3" bullet tweeter set inside the over 3" voice coil cavity (bolted in through the vent hole) of a good 10" bass/med PA driver (with huge magnet). The Tweeter has to be ridged cos the tweeters are heavy. One girl described the sound of the PA speakers as "live" and another person raved about them heaps. I "cranked" them and the sound is so loud but "undriven", the tweeters are cheap but good and efficient and sting loud without sounding forced, the sound just oozes out! The tweeters are horn loaded and have heaps of go. It sounds "live" cos it has cos there is enough high end, and med is as non colored as I can make it and also point source phased aligned sound. Full range speakers are point source but unless you pay through the nose for them, they won't have near the "image" as two-way point source speakers do. I reckon it's simply cos cheap full range drivers don't go high enough. They have good "clang" and good "ding" but no high "tizz". No ride cymbal and so no really high stuff that seems to make the "image". And no matter what you do to a cheap full range driver it won't go there, that simple. It must be cos the cone and the coil etc. is so heavy compared to a tweeter's (even with satellite full range speakers). My second set are 8" two way point source speakers and cost about $500 to build. A lot of the cost is the crossover (especially the chokes) and making the crossover to my satisfaction is about the most difficult part (but I'm much better at it lately). The 8" bass/med is a good quality "Guitar" driver (with a large magnet) and it has a 2" voice coil and I mounted a 1.5" soft dome tweeter inside the voice coil cavity. Same "live" sound but better at low volume than the PA speakers and the PA speakers are way better at high volume than the lounge speakers. The large drivers of the PA speakers need to be driven to sound their best (poor transient response at low volumes). But I have compensated so they still sound good low, I put some med (highly resisted) into the tweeters (that have way better transients). This isn't new, KEF did it with the tweeters in their (vintage) C20 speakers. I know, cos I got some. lol But I didn't copy the med in tweeter idea, I did it before I got my KEF C20's. lol It makes a large driver sound amazing in the voice (for how large they are). I invented a new type bass vent. The bass vent is all around the bass/med driver (point source) and still works as well as any bass vent. I experimented with an acoustic ring (at a certain depth) attached to the speaker driver hole and running inwards. And the driver is also "floated" by spacers like 3mm above the speaker hole. It not only acts as a point source vent (making the speaker 100% point source) but it also "chuffs" up the med and makes it sound way less "boxed-in" with the voice sound. With large drivers this makes the voice sound less "boomy". I have this type vent on both sets of speakers. And that was the original reason I tried “floating” the speaker over the hole, to try and improve voice sound with a large driver, not for point source reason. Then I innovated to improve the shocking bass sound and came up with the acoustic ring, point source bass vent. It pumps. I'm going to build two more sets of speakers (different concepts). A two way point source with extra woofer, with a 3" bullet tweeter and 6.5" med (with over 3" voice coil) plus an extra non point source woofer. those drivers are one-of-a kind and discontinued. And a planar type speaker (I want to build from a drum skin, driven by an old driver). A tweeter will be (not quite) in the center. "Not quite in the center" in the hope to tame resonance. A hole will be cut in the drum skin (not tightened too much) and the back driver unit (driving the drum skin) will be applied to the drum skin in the right way and a tweeter set in the hole in the drum skin. Also a separate woofer will be fired onto the floor (downwards) like a half inch above the floor. I'm also building my own bass/med drivers from old drivers so I can make the hole in the center of the cone larger than the voice coil cavity. First I get rid of the original cone, then I am making a base 2" diameter out of soft foam (stiffened with toothpicks) glued on top of the voice coil tube. Then another 2" "voice coil tube" connecting the soft base to the new remade thinner cone that will be higher in the center than the original cone (less conical) and connected to the top of the surround, not the inside (so it's higher). Less excursion but a med cap will be on it to stop bass below 100 hz for a more “still” more defined med (and extra separate woofer). The soft material base (in my built med driver) won't make much sound even being horizontal and the vertical cardboard tube won't either (being vertical). After hearing my point source speakers I will never listen to "normal" speakers again.

me three Paul

Again it is a tradeoff. For a given SPL, if you want low distortion, you need to lower the displacements of all the cones. More cones = less distortion BUT bigger boxes. Remember this. You create SPL by displacing air. You either love a large surface a little or move a small one a lot more. More movement generally means more distortion. But large surfaces require bigger boxes. The tradeoff of box size is eyeopening and Paul should do a whiteboard on that. It will be easy to understand why the last octave is so hard to get.

Laporello Gatos sorry, I am not Paul, but in my humble opinion, high power amplification is always a better starting point for everything (regardless of whether efficient or not efficient speaker). It's like motor in the car, at the ''end of the road'' is always better to have a motor with a large volume and lots of horsepower, it can run whatever it wants... The only condition is that there is ''gasoline''... (Sorry, again, on English.) Peace

Thank You Dragan! Personally, I follow that philosophy too. Having said this, there's people that suggest that, with high power comes more difficulty to control distortion to acceptable levels and of course, if we talk high power Class A, we need physically huge boxes with ample cooling heat sinks etc. etc. In our local audio club, there is people that use 'flea' power ( 2 - 8 Watts !!) with single end triod amplifiers and horns that are 100 + dB! Thence my question to Paul. Thanks for answering me though, always interesting to read what other audiophiles think. :-)

@Fester Blats, Power in amplifiers does not always translate into "better" or expensive. Most low power amplifiers come in the form of a Triod single ended valve (or tube) that are very well constructed and, some, cost the earth! Look here: www.6moons.com/audioreviews/ancient3/single6_2.html and here: www.dagogo.com/teresonic-reference-2a3-integrated-tube-amplifier-review/ ..and an extreme case from Japan at $ 79 k (!) here: www.dagogo.com/audio-note-ongaku-integrated-amplifier-review/ I hope I convinced you that power / better / price don't always go together.

Thank You. 😀👌

Neo allows for better venting and less reflections from having a big object in the way :)

the only downside to Neodymium is the heat problem..maybe if doped with Dysprosium it could handle higher heat without losing its magnetism.

steve mcdonald thank you for the help. 😀👍

"what magnet type do you like neodymium or ferret?" Defintely neodymium! Ferrets object to being magnetised and will inflict a nasty bite if you're not wearing leather gauntlets. My missus doesn't like that they also piddle on the carpet.

I heard a pair of Zu's once powered by a $13,000 4 watt tube amp (Whammerdyne Ultimate Truth). I wasn't doing any critical listening, but they sounded impressive for such a small amount of juice. Still, this more careful test and teardown of them was much less impressive: noaudiophile.com/Zu/

They have made a lot of changes since that review. LOL.

sorry that they sound just average....

Dinamo I got some old Seas speakers from my granddad. They do sound better than any of my newer speakers

B&Ws not that great at all and with a sensitivity of 90 I don't consider that to be anywhere close to being high sensitivity.

Nerium Oleander I had some Cerwin Vega E715 a few years ago. They were rated at 102dB! Zero soundstage but made a nice sound!

See? Compromises.

cp070476 Missed your response somehow, It depends on the design. If a design is done properly with said sensitivity you can certainly get a sound stage. The type of application and design would also allow for it as well. John, Engineering is about compromises, but high sensitivity does not mean there will be no sound stage. If you have no sound stage, something is not done right or it maybe characteristics of the driver or design. Competent designers are necessary to be able to able to do this and there isn't too many. I'm talking 105dB + sensitivity 25hz to 20khz not a one note measurement. And to add on top, no weird peaks or horn designs where something would sound off. Further? Acoustic power of 140dB + without kilowatts of power that you see which is the easy way out. Another often miss is Mid-bass. My current system is does not have said capability and is only 101dB/w for the mains. However, a high motor strength motor with cooling for bass and especially mid bass handling is outstanding for size considered. But that's with 4.5kW, a 2nd amp would allow for 10, motor has been tested at peaks far higher however. Likely the most powerful sub for it's size with this amount of mid bass capability, dynamics, distortion and impulse response is also excellent. This would be beat up by the next system, thoroughly and will be built by someone else that has vastly more experience than I do and will not be the same person that built my current system. Hopefully getting my hands in the process. Possibly a look at the design process of said drivers too as well. The engineer can also be the compromise of a system even when you have outstanding drivers. Compromises can always be minimized. It simply depends on how capable the engineer is and how far and how long he will take it to refine the performance.

B&W are gimmicky speakers built for lawyers and doctors to show off how much money they make..like the Genesis 900

Gary Smith I doubt Paul M will give Paul K a nod but i will!

Thank you Scotty! I find it interesting that Paul M.'s beloved friend 'dabbled' with Klipschorns back in his day... Yes, Arnie himself mentioned this during HIS OWN introduction in another video on youTube (Rocky Mountain Audio Fest #15)... You can find it easily enough by doing a search on that title.... (O;

Yes, it’s call the Iron Law of speaker design. You can have high sensitivity, deep bass, or small cabinet size. You can have any two, but never all three at the same time. As for the Klipschorns, they do produce deep bass, deeper bass than should be possible for a cabinet that “small”. The trick, Paul Klipsch’s master insight, was to place the Klipschorns tightly into the corners of the room, and use the walls as extensions of the woofer horn, which the cabinet already folded, so as to give the effect of nearly an 8-foot horn inside the cabinet. Deep bass notes have very long wavelengths, measured in feet, not fractions of an inch, so deep bass horns are huge, like 10-20 feet long. The Klipschorn gets around this very cleverly. However, not every home has suitable corners for Klipschorns, so the La Scala is the logical next choice. Its bass horn is less than 4 feet long, so its bass response doesn’t go as deep as the Klipschorn. Luckily, we now have a big selection of subwoofers to help it with the bottom 2 or 3 octaves of sound. A La Scala and a good sub or two can actually sound better than a Klipschorn, so you can get that great Klipsch sound in a smaller package, and not have to stick your speakers tightly into the corners. As for wife’s impressions, Paul Klipsch was way ahead of most other speaker designers. As he became more successful, he could afford a home with bigger rooms, but the Klipschorns still had to fit tightly into the corners. The problem was that once they’re more than 16-18 feet apart, there’s a “hole in the middle” effect. To fix that, Paul invented the world’s first centre speaker in 1957: the Klipsch Heresy. He also invented an electronic box that could sum the Left and Right channels to feed the little Heresy. Later, after he invented the La Scala in 1963, he decided that it would be a much better match with the Klipschorns as a centre speaker. He was right. The combination of the 3 speakers sounded great, but his wife Belle objected to the looks of the stage-ready black-painted Utility Finish of the La Scala. It was the first recorded instance of WAF (Wife Acceptance Factor). Don’t laugh. That’s a real concept. To please his wife, Paul Klipsch built a “house-trained” version of the La Scala: the Belle Klipsch. It was much prettier, and it was named after her. We can only assume she was pleased, because I’ve seen no record of her reaction. The Belle Klipsch was in production from 1971 until 2005, when the La Scala II was introduced, which had many of the style features of the Belle, with slightly higher performance, so the Belle became redundant and production of it (her?) ceased. Paul’s wife Belle died years before then, and he remarried. The new wife, Miss Vickie, got a speaker of her own as well: the Golden Jubilee, but only one pair was produced, for her only. Paul died in 2002, but Miss Vickie, his widow, still happily listens to her Golden Jubilees.

It's already available..

Indeed, it's a shame there aren't more loudspeakers out there that are true all-horns to maintain high to very high sensitivity across the entire frequency range, and by the same token share the same and very important sonic traits like effortlessness. It pays off big time, sound-wise, so If they're making a statement product at those price levels, why don't go all the way? There are excellent tapped horn subs out there that extends to almost 20Hz flat, deeper yet in-room, and at a relatively sane 20 cubic feet enclosure volume, like Danley's TH50. It's "only" some 97dB sensitive, but that's the price for a close to 20Hz low corner.

And they are about $3500 each. Many of us cannot, or do not choose to spend, $3500 on a sub. Compromises.

Google "Royal device" marctwyman.blogspot.com/2006/05/royal-device.html

Yes. Absolutely. If you want to use a low powered amplifier it is important to use very sensitive ("high efficiency") speakers. If you have a very powerful amplifier you have more flexibility, but sensitivity is always desirable in speakers. The problem is that high sensitivity speakers are usually larger and/or have less ability to produce bass sounds. The trade-off formula is usually seen as three parts from which you must choose two: bass response, cabinet size, sensitivity. Obviously there is a compromise to be made. If you can have massive speakers, you can drive them with a low powered amp and have great sound. If you have a very powerful amp you can have small speakers with decent bass. If you have small speakers and a low-powered amp, you can have great sound without much bass. Or you can spend a lot of time (and quite possibly money too) to find the speaker that strikes the perfect balance for you. It's the sort of pursuit most audio nuts find thrilling. Good luck!

I have a pair of Altec Valencias for sale. Perfect for a tube amp system. They need a good home with lots of space. I am the original owner.

tonkatoytruck Thanks but I'm looking new

tonkatoytruck what state or metro area are you in? Those Altec Valencias would be great for the right person, but I wouldn't want to have to ship them.

Houston, Texas Thanks for taking time to comment. They have been a lifetime of enjoyment and deserve a good home.

How much spl is really wanted and what is sensitivity of one's ears too matters here. Also needs a frame of reference to yearn for the awesomeness one perceives. I am almost always happy with THX audio even for my mediocre listening needs and tastes. I am not a serious listener of music and have more inclination towards home theaters. For music a pair of Sennheiser and Wolfson audio with super curio mod for android still is best overall performing audio combination for those on budget like me. The next step could be THX AAA amps. Having a dual Wolfson dac amp with discreet power supply etc remains a dream for me. If I can afford a linkwitz 521 with hypex and ncore remains the ultimate dream setup for me. I hope it just gets better and cheaper with innovation. Late Siegfried Linkwitz has shown the way forward imho.

Ser Loin of Lamm I'm super curious about what those are. Did anyone identify them yet, perhaps in the video from yesterday?

Andy B I'm assuming the electrostatic with a bass bin

Mine are upside down on my desk to make it ear level

Found the answer with help from Paul's response to another person: ERA Design 10. They are out of production now.

Many class D amplifiers get lower distortion with higher power before they clipp and the distortion goes through the roof.

This varies depending on the type of amp. Class AB this might be true, class D the opposite is the case.

The "perfect speaker" is the one that reproduces sounds like the sources with which you are familiar. I love the grand piano. In my place, we sing around the piano. I go upstairs to my studio and crank up my big speaks and they sound within 99% of the live performance I just left. But we are talking about systems weighing 236 lbs. a pair and having an efficiency of 102db from 1 watt@ 1 meter, hardly the thing the average music lover wants or needs. None of us need to go 200+ mph in a supercar , but it's fun once in a while on a desert road.