@mijostyn --
The best performance comes from electrostatic speakers. They are generally mid efficiency speakers but are very amps sensitive and owner sensitive. Otherwise it is 6 of one 1/2 dozen of the other. The best performance I have heard come out of dynamic loudspeakers came from inefficient speakers driven by huge amplifiers.
One of the best setups I’ve heard comprise rather inefficient waveguide-fitted "dynamic loudspeakers" (S.P. Tech Revelation, actively configured and subs augmented). It’s the whole shebang; listening room, components chosen in every department, modifications here and there - just overall brilliant implementation by a guy who’s a total wizard in this field like none other I know. He assisted Bob Smith in the development of the S.P. Techs, has a tech background in electronics, years of experience in a high-end audio shop, crazy good ears. All this to say that whatever speaker principle he would be handed with complementary gear and all, he’d make it sound absolutely great I’m sure with mods and what not. It would be interesting though to see the absolute "level of perfection" he could wring out with whatever speaker principle he’d be given, but it’s a process that doesn’t come overnight.
Generally though low efficiency, direct radiating and not least passively configured dynamic loudspeakers (even with huge amps, which are really just a symptom of a severe bottleneck in the chain: the passively driven low eff. speakers) are at the bottom of my speaker ranking, then electrostatic speakers (which I haven’t heard actively driven nor as floor-to-ceiling height models like your Sound Labs), and at the top (no surprise there) are large(!) high eff. horn-loaded speakers, be they hybrids or all-horns. Those have been the best where they were fully actively driven with DSP filtering and solid state amps, actually, and not the perhaps more common pairing with low wattage SET’s or the likes as passively configured speakers.
You may feel inclined to give me the rundown on how I haven’t yet risen to the level of accuracy, but I’d dodge such a suggestion or even as a bluntly stated fact with mere indifference; I know what I’m hearing, I have my (live) references and preferences for how to rather effectively emulate such a ref. in vital areas, and not too few years of experience under my belt. I have my tastes (i.e.: preferences), sure - so do you - and the fully actively configured high eff. large horn-loaded approach just ticks off most of the core "pillars" in sound reproduction with the least bottleneck-feel to it to my ears. Even my friend’s S.P. Tech setup mentioned above, as great as it is, comes up short in several areas compared to my own ditto (and I’m just honest here; to hell with modesty), even though it’s not as well implemented overall as his system. Tonally though our setups are very much alike, which is interesting given the differences with our speakers in particular, but on the other hand it may not come as a surprise being that we share core sonic preferences, and also that he's been instrumental in the tuning process of my own system.
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@tannoy56 wrote:
@larryi What would you say are the attributes of low efficient speakers? Anyone?
IMHO, compared to higher efficiency speakers typically incorporating horns or waveguides at least as hybrid designs (in conjunction with a direct radiating woofer/mids) or more radically as all-horns, a very general observation could be made that low efficiency, direct radiating speakers are less dense and present/direct sounding (paradoxically perhaps when being called 'direct radiating'), while also being dynamically more muted (and less lively overall). Low eff. speakers sometimes have an airier presentation, perhaps due to involving more reflected sound and having a more laid-back, less full sounding imprinting. Very good high eff. speakers have this "lit from within" and ignited quality that really makes music spark and come to life effortlessly, and the larger iterations have a fully immersive and physical yet relaxed presence to them that's quite addictive ones you get used to it.
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@larryi wrote:
Thank you for an excellent description of what is most prized about the sound of high efficiency systems, particularly, horn-based systems.
Glad you found it worthwhile.
While good design of such systems will ameliorate midrange "peaky" or "nasal" colorations, such systems do tend to be a bit less smooth in frequency response than better low-efficiency direct radiating speakers. I hesitate to say this because so many people have heard grossly uneven horn and wide range high efficiency driver systems, and do associate such systems with such coloration, but I will say that such problems can be effectively ameliorated in better designs. Still, I can see why such systems will not be to everyone’s taste.
Smoothness, or lack thereof in frequency response can definitely be a factor, I agree. Great horns don’t really sound like horns (if there even is a decided consensus about what horns in general sound like, and with the implicit notion here perhaps that "horn sound" has a more or less distinct character), and the bigger they are even less so, I find. Yet, large and great horns definitely don’t sound like smaller, low efficiency direct speakers either, but are in some respects more reminiscent of very large panel speakers. Indeed I would go so far to claim that some don’t like horn sound just by virtue of it sounding different compared to low. eff. direct radiating speakers, even if the former are devoid of uneven frequency response or colorations in general.
@audiokinesis wrote:
Very often the limiting factor for high-efficiency systems is the on-axis frequency response at high frequencies. And one way to get very high efficiency numbers is to use a horn whose pattern at high frequencies is very narrow, such that all of the high frequency energy is concentrated in a narrow beam, thereby maximizing the on-axis sound pressure. If the same compression driver were used on a wide-pattern horn, the same amount of acoustic energy would come out, but because it’s spread over a wider angle the on-axis PRESSURE would be less.
The EV Constant Directivity horns (HP9040 + DH1A) on my EV main speakers, by virtue of not narrowing the HF response on-axis, should require equalization in its upper band above some 3kHz, at least for their intended cinema use, but surprisingly we’ve only found it necessary and most important to apply some notches and a peak suppression via a Xilica DSP (active config.). This ameliorated a slightly can-ey and mechanical imprinting for a very smooth upper band reproduction. The lack of a need for an EQ gain-boost in the upper octaves I’m guessing may have to do with the limited spacings they’re now used in vs. large auditoriums, with the former providing some boundary gain. What’s your assessment here?
Some horns have coloration, which imo eliminates them from serious contention. At the risk of over-generalizing, I’d be wary of horns which have sharp-edged internal "kinks" and/or sharp edges around the mouth.
The EV horns of mine both have a diffraction slot and sharp edges at the mouth area, and so may set the alarms ringing in many a horn-audiophiles’ head, but they actually sound very smooth after being properly implemented with mentioned DSP filter-actions above.
What’s less discussed or acknowledged even is the importance of horn size and its sonic implications. This is also a factor determined by the compression driver used here, with the very powerful DH1A being more properly loaded with the HP9040 horn compared to the smaller HP940 sibling (which I used previously). The DH1A simply seemed to "shoot through" the smaller HP940, but the sonic outcome also had to do with the horn resonance being placed higher in the upper mids on the HP940 vs. in the lower mids on the HP9040.
In any case a larger horn appears to fold-out the sound much more effectively for a more relaxed imprinting than a smaller horn, while also sounding more fully developed physically. Things being equal a smaller horn sports the more intensely "directed" sound (to many perceived as a horn-sound characteristic?), and the larger ditto has a much larger, even a huge and more relaxed sphere or bubble of sound.
I know horn geometry and diffraction eradication found in newer horns is very important sonically, but you come a long way with blunt, physical size in older more industrial (and still very well developed) designs, I find. Size is less sellable, though, and many don’t like the mere association with pro segment products.
Thanks for your great contributions, Duke.
@johnk --
Well put.
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@audiokinesis wrote:
[...]
All of the above speculative explanations are unlikely, perhaps even highly unlikely, which brings me back around to "I don’t know".
Sorry about that!
Duke
No need to be sorry - on the contrary, thanks for taking the time to investigate on the matter! And to come up with some theories that could explain why no EQ-gain in the upper octaves with my CD horns/comp. drivers is necessary. I’ve had several people (audiophiles most of them) listen to my setup, and none of them have addressed (even when eventually asked) a lacking HF performance/extension or a possible frequency imbalance, though I can say for my own part that the very smidgen of upper bat territory range they don’t cover, and I’m fine with that.
@asctim wrote:
Good phrase - "alarms ringing" since that’s what the sharp edges cause worry of - ringing. I get the impression from my listening that the ringing back to the throat is generally fast enough that it doesn’t cause the kinds of issues that I thought - peaky, ear piercing response types of sounds, although perhaps it can if the horn is big enough. I’ve heard some of the really big diffraction horns bothered people in the past but it could be they just weren’t well equalized. So I think I agree with you that properly equalized diffraction throat horns can still sound quite smooth and natural, although some imaging and detail might be obscured. The better high frequency dispersion may be more than worth it in many scenarios.
Thanks for your insights. Many factors certainly come into play on how to properly assess a given horn/comp. driver combo, and in this case a Constant Directivity horn with a diffraction slot and relatively sharp (i.e.: not large diameter rounded) mouth edges. Some people on principle just shy away from such a horn type, which is a shame being there are several examples of them sounding very, very good. It’s mostly about the implementation, size is a factor (i.e.: the bigger ones, many things being equal, sound less like horns and often downright awesome), and the intended usage. You could be right on details/imaging being slightly obscured here, but my advice would be for people to listen first and then "judge;" much of which is passed around on the supposed deficiencies in this regard is really just speculation and assumptions, or certainly could stand the test of being evaluated more closely for the relevance and degree of such speculated deficiencies.
@johnnycamp5 wrote:
I always thought it was slots or discontinuities in the THROAT of a horn that could often cause a “spitty” or sibilant sound compared to an identical horn with a smooth throat…
Relative to the specific horn in question these "spitty" effects, if they do occur, would normally only do so at prodigious SPL’s. The levels where this might happen is close to bonkers, with my own EV horns (and only assuming the effect will happen, if it even will) this would be somewhat past 120dB’s, far exceeding what most sane individuals would expose themselves to.
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@mijostyn wrote:
SET amplifiers are about as silly as cable elevators.
Don’t agree with this however - that is, regarding the SET's.
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@mijostyn wrote:
horns are a very alluring proposition. They are efficient and there is no question they can play louder than any other type of system with low levels of distortion. You can also control the radiation pattern to limit room interaction, another big plus.
Indeed. More though than the ability to play loud with low levels of distortion is their sound at more average SPL’s with even lower distortion and the sense of aliveness in music intact (which may otherwise require higher SPL’s), the ease of reproduction this offers and the prodigious dynamic headroom that allows uninhibited transient peaks and full dynamic swings. The ability to play loud well isn’t really about stretching this envelope to the max., not to me at least, but (to stay in the car analogy) to feel that the engine has power in reserve for any occasion readily at your disposal (i.e.: sense of effortlessness), as well as - and not least - a sensation of inherent power lurking beneath. The sense of power in sound reproduction (all tied into the above) is vastly underrated, if you ask me.
Unfortunately they fall short for a number of reasons. There is no such thing as a full range horn. You are forced into having a crossover somewhere in the midrange or upper bass. Many horn systems run a dynamic woofer well into the midrange, so much for low distortion. It would be a complicated mess trying to make a line source horn system.
True, the wretched cross-over(s) and where to place them. ESL’s no doubt have a big advantage here. Trying to emulate a line source is not necessarily the goal though; within the limitations given here my effort has been to reduce the number of cross-over points down to a single one in the main speakers, and focus on maintaining dispersion characteristics at this chosen point from the dual woofers up through the horn. Being that the sound emanates from this +6 ft. radiation surface is not wholly unlike that of a large panel speaker - in its overall presentation at least. With steep filters (6th order) via a DSP and a HP on the woofers at 83Hz and a LP at just over 600Hz, distortion subjectively is very low. They move zilch even at bonkers SPL’s.
Line Source systems are the only way to get into the first 10 rows. ESLs can cover 100 to 18 kHz no problem, no crossover. They maintain the lowest distortion levels throughout that range. Crossing to a sub at 100 Hz is much less of a problem especially if done with steep digital filters.
Absolutely - ESL’s are widebanders in ways dynamic loudspeakers can’t equal. You can however effectively emulate a single source merging several drivers in a single horn as Danley’s Synergy Horns, and as far as distortion levels go - depending on where we look for them - they can be vanishing low via horn speakers as well. I have an 111dB sensitivity horn/comp. driver combo looking directly into a class-A amp with no passive filter components in between, using only factions of a watt with normal playback. That’s way low distortion levels.
The only disadvantage ESLs have relative to horns is that they are much less efficient. The fact that they won’t play as loud is not a problem because they will do 105 dB and anything louder than 100 dB is certainly damaging your hearing.
The occasional peak levels of +100dB’s found in live acoustic performances or non-compressed recording playback isn’t a problem, it’s blasting away at continuous loud levels with compressed material that will take its toll on the ears. Oh and of course instantaneous mega loud blasts like explosions or other can also be severely damaging on ones hearing.
And to reiterate: to do 105dB's peak cleanly at the listening position you need way more SPL capability than that - at least if you want to know what effortless playback really is.
I am a huge proponent of actively driving loudspeakers. This does not mean that all the wizardry has to be within the loudspeaker. You can actively drive any loudspeaker with outboard components. I have been doing it for 20 or so years.
Fully agree, it’s what I do myself with outboard components (though not for 20 years - kudos).
There is no other way to get the absolute most out of any system and this is not IMHO. I have seen, heard and measured enough to know this is a fact. If there are any downsides to this they are far outweighed by the benefits. Trying to maintain a totally analog system is like owning a vintage Corvette. If you are a track junkie you will go a lot faster in a C8. I’m not into owning antiques. I like driving fast.
Won’t argue with that either, but I certainly respect and acknowledge that very good sound can be had in passively filtrated speakers.
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@mijostyn wrote:
we have to disagree about something. Try driving an ESL with a SET amp. Do I smell something burning?
And it ain’t the toast. No, SET’s for when they make sense; with high to very high sensitivity speakers to take advantage of the less than 1 watt where the distortion levels found in these amps are extremely low here, just like with the speakers they’re feeding that efficiently turns electrical power into acoustic energy. Think about the power that’s wasted as heat with low sensitivity, passively driven dynamic speakers, not to mention the poor cone/diaphragm to air coupling - waste upon waste, really. It’s all about the most efficient transfer, and lastly from the speakers to the ears and how to "capture" the acoustic ditto here, which is also a reason why I’ve never dug heavy absorption - it potentially makes matters worse energy-wise:
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@charles1dad wrote:
Yes, this accurately describes my copacetic listening scenario. 8 watt SET mono blocks driving 94 db sensitivity /14-ohm impedance speakers. My typical listening levels sitting 10 feet away are C-weighted 65-75 SPL
Can dip to the mid 50s (softer passages) most ofren peaks (mid 80s).. I can listen at louder levels comfortably, but no need to.
About the same levels for a large portion of my music enjoyment (right now averaging just over 65dB's C-weighted with my evening listen of Keith Jarrett's 'The Carnegie Hall Concert'), except with a range of well-recorded and not too dynamically compressed classical recordings, some electronic genres and watching movies, where higher peaks (via a wider dynamic range) do occur.
At these very satisfying listening levels the SET is far below 1 watt of power (Small fractions of one watt) and doing so at a very low level of distortion (As you note). The sound is very tactile, resolved, pure, natural and quite emotionally engaging. Key take away is the amp and speaker must form a compatible match.
Charles
With 8 watts of SET power given the speaker context, listening levels and distance this combo should be perfectly suitable. Sounds to me like you're hitting the right notes, so to speak, from your descriptions.
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It’s about the implementation and physics. Sure you can have, say, 97dB sensitivity and honest 20-25Hz extension - that’s from a tapped horn at 20cf. volume with a high-ish fs (35Hz) pro 15," proper motor strength, not too low mms (i.e.: +150 grams) and overall complementary parameters for its specific use. The horn does the heavy lifting and fills out the extension and amplitude gap the driver normally couldn’t handle. Way smart.
I would be cautious pairing high eff. main speakers with low eff. subs - it doesn’t really gel. You want high eff. and extension to boot you go the distance with size to follow and high eff. all the way; it pays off sonically and certainly is realistic - where there is a will to let size (and the required design) have it’s say.
Run it all actively with high-passed mains and treat it as one speaker system pr. channel incl. subs with carefully implemented delay settings and overall filter parameters via a capable DSP - not just with the latter patched on where the (passively configured) mains roll off naturally. Just my $0.02..
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@johnk wrote:
It’s just wrong to think that hi eff doesn’t do low bass I have bass horns that can bend doors and make your eyes resonate some I designed are used in military simulators to replicate explosions and gun fire. Just because in your limited experience you haven’t heard deep bass in hi eff doesn’t mean it’s not available. It just means you made major compromises in size.
Exactly, John. I expressed a similar view in my latest post on this thread page some two months ago, but it went to deaf ears/blind eyes, it seems.
It must be said though people don’t need +100cf. behemoths to experience high eff. bass to 20Hz. 21"-loaded high order bandpass subs with 100dB sensitivity will do honest 25Hz from a 16-17cf. volume, and my own tapped horns are 20cf. per cab @22Hz. Even so most audiophiles are likely to bark at such sub cab sizes, and so there’s only so much one can do.
@larryi wrote:
But, I have never heard these systems deliver really low bass at a high level. I just don’t care that much that they don’t do subwoofer stuff and I don’t really like subwoofers in these sort of high efficiency systems. [...]
Which kinds of subs have you heard paired with high efficiency mains - low or high eff. subs (i.e.: smaller or very large subs)? I don’t find high eff. mains pair well with low eff. subs, they just don’t mesh properly. If however high eff. can be maintained across the whole range, another matter - given of course mandatory care taken with implementation. I prefer crossing fairly high to the subs, typically no lower than 80Hz, and with the mains high-passed accordingly - fully actively (mains + subs), if possible. That, to me, offers the best opportunity for a coherent, fully integrated presentation.
If on the other you’re perfectly OK sans subs, all is merry, though if you have yet to experience the right high eff. subs in conjunction with your mains I would say you’re potentially missing out on an extraordinary sonic meal. Pardon, I may be presumptuous..
I like Rolls Royce’s specification of horsepower in the old days: "Sufficient."
Haha, stated with confidence indeed :)
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@atmasphere wrote:
My Classic Audio Loudspeakers are 98dB and flat to 20Hz. They employ dual 15" woofers as well as field coils to reduce distortion and compression while increasing speed.
I guess one could even argue, given their 16-ohm load, that they're 101dB sensitive from the usual 8 ohm standard sensitivity is measured by. Not to mention that many speakers today are closer to a 4-ohm load, yet without being accurately reflected by their sensitivity rating..
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@kennyc wrote:
Some members seem to advocate whether high efficiency speakers are better or not. Sonics is my priority not speaker efficiency. I only address speaker efficiency if it is required/driven by a sonic goal- wanting to hear flea watt 300b tube amp magic which would necessitate a very efficient speaker.
High efficiency speakers aren’t necessarily better, but high eff. in itself can have a significant advantage going for it that impacts (or is brought to realization by) a range of factors like size, driver types, acoustic transformation and dispersion characteristics, and this in turn has sonic implications that’s also about ’different’ rather than just better/worse. It’s not like we have two pair of speakers that look exactly alike with the same drivers and all and a similar frequency response with the one pair being low eff. and the other high eff. Comparing high eff. speakers with low eff. dittos comes with several factors "interfering" that are linked to high eff., but extracting high eff. from that "equation" would seem to shortchange the bigger picture of what’s involved and that has significance sonically.
A very high eff. speaker system over its entire spectrum with a wide frequency range (say, down to 20Hz) will by necessity be large to indeed very large and horn-loaded (its total size depending on the specific implementation of the upper bass to midrange horn in particular). If well implemented and given proper horn size and acoustic surroundings (i.e.: mostly about size also), such an all-horn system to my ears potentially is in a very different league compared to smaller, low eff. speakers, with a sound that’s much more akin to a live event presentation, be that acoustic or amplified. To some this quality mayn’t be of vital importance, nor may they be able to or don’t want to accommodate such a system in their surroundings (cost may also be a factor), but nevertheless these qualities are undeniable and on full display.
As with many things as well as high efficiency and its significance though, it depends.
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@alexberger wrote:
In my experience, each pair of speakers that isn’t driven easily by 30 Watt amplifier - sounds too compressed to me.
That outcome is also very much dependent on the specific amplifier used. I’ve heard a very good 30W pure class amplifier drive a pair of notoriously heavy load S.P. Technology Revelation’s rather effortlessly, whereas coupling them to a pair of 200W NuForce monoblocks felt like those amps struggled by comparison - even though, on paper, they’d have a +6dB headroom advantage.
Which is also to say that the sensitivity rating is only a partial signifier; a complex passive cross-over can bring many a wattage proficient (but apparently PSU weak) amp to its knees, with the same amp performing closer to its full potential and rated specs presented to an easier load. A more load benign amp requires a sturdy, powerful PSU, and those things come at a cost.
On principle though we fully agree. A difficult to drive pair of speakers, likely due to the "load severe-ness" as caused by its XO, presents a significant problem to me that only highlights why I’d rather have it configured actively sans passive XO, but that’s another discussion. High eff. passively configured, heavy load speakers would likely prove less of a hassle to the amp given that it has more headroom to deal with a complex XO.
And it easy to explain. When you put dozens watts on speakers voice coil - it overheats that leads to very sever and clearly listened compression.
In practicality I’m inclined to believe thermal modulation (as term also used by poster @audiokinesis) is the more general problem, as this comes into effect with peak heat build-ups in voice coils (and XO?) with short term transients, that dulls the perceived transients somewhat. It seems this phenomenon is less a studied field, but it could explain with why transient snap sounds more convincing with high eff. speakers.
Not to say thermal compression isn’t an issue with low eff. speakers. Dynamic prowess and their fuller swings certainly takes a hit here.
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Few bring up high efficiency subs from a point of home experience, probably because they take up too much space (i.e.: Hoffmann’s Iron Law), and yet others seem not to believe high eff. down into the lower octaves is even possible. Well, it is, and there’s no way around indeed very large size here.
What may surprise some is that despite being highly efficient, many if not most such subs still require sturdy, very high power amplifiers to properly run the typically large diameter woofers with big voice coils and relatively heavy cones. Depending on how these drivers are loaded in their specific designs could mean yet another factor that stresses the amplifier, so that even at lower SPL’s it becomes obvious whether a given amp controls the woofer/design properly. I recently went from a 500W/8 ohm class I (iteration of class D) power amp driving my tapped horn subs to a 1.3kW/8 ohm class TD ditto, and with 97dB sensitivity one would gather no more than around ~20W would be necessitated for general use, making such a swap/power upgrade seem meaningless.
However, the fact of the matter is that the more powerful/different amp is able to have the woofers of the TH subs resonate the horn much more effectively, which is clearly audible/sensed at quite low SPL’s. Turn up the volume and that sensation is viscerally magnified, so much so that one quickly realizes the intimidating (and thrilling) power such a design is capable of.
Is it all all bonkers then - why such a powerful combo of high eff., extension down to 20-25Hz (at full tilt) and a bucket load of power to boot? Because it sounds so utterly effortless, smooth, inherently powerful and immersive at any desired SPL, but not least also at more "sane" and even low playback levels. Many an audiophile isn’t aware of that. Moreover, when the bass is so clean it means that it can (and should) be dialed higher in gain, because less clean and too conspicuous sounding bass is usually dialed lower and in fact too low for it to have proper fullness and presence in the sonic presentation.
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