How important is the efficiency of a speaker to you?
I went to an audio meeting recently and heard a couple of good sounding speakers. These speakers were not inexpensive and were well built. Problem is that they also require a very large ss amp upstream to drive them. Something that can push a lot of current, which pretty much rules out most low-mid ( maybe even high) powered tube amps. When I mentioned this to the person doing the demo, i was basically belittled, as he felt that the efficiency of a speaker is pretty much irrelevant ( well he would, as he is trying to sell these speakers). The speaker line is fairly well known to drop down to a very low impedance level in the bass regions. This requires an amp that is going to be $$$, as it has to not be bothered by the lowest impedances.
Personally, if I cannot make a speaker work with most tube amps on the market, or am forced to dig deeply into the pocketbook to own a huge ss amp upstream, this is a MAJOR negative to me with regards to the speaker in question ( whichever speaker that may be). So much so, that I will not entertain this design, regardless of SQ.
Dear @lonemountain : Yes, today TAD speakers are not exactly high efficiency at 90db and are expensive but its sound quality level performance is excellent.
In the past Exclusive in Japan ( Pioneer ) had the 98db big 2401 Twin model obviously all TAD drivers and in Japan in those early 80's its retail japan price was 1,200,000 Yens and a direct competence to JBL and other USA speakers or from England as the Vitavox.
TAD today monitors for home audio are in the 85db efficiency and excellent performers too.
@lonemountain : Now I understand why for you is important but not so important the speaker efficiency issue. I visit your virtual system and seems to me that you are an audio distributor od low efficiency ATC speakers.
@phusis " the claim that high efficiency is necessarily and always bound to be attained "with a price," sonically speaking, is a fallacy. Typically it comes down to (the need for) large size and a different speaker principle.."
Well , that large size is not exactly typically " because depends on the kind of drivers other than horns and an example are my ADS speakers that yes are " large size " but the size is due that the speakers can goes down to 16hz through two 14" acoustic suspension woofers but today I have the ADS from around 100 hz and up and the soft domes ( silk ) acoustic suspension 2" for the mid-range and 1" for the tweeter ( one a top the other:nearest as it can be. ) needs a very small " box space " due to its very high gauss magnets ( are not vented and non-ferrofluid. ) around 24k in the tweeters and 18K in the mid range, both drivers made it in Germany for ADS and its efficiency is 95db ( almost a horn . ). Unfortunatelly the drivers manufacturer just does not exist any more.
it’s true - I am ATC USA and do not want to hide that. Previously I’ve worked for EV (their rep out of Chicago including OEM)and JBL (in charge of cinema and installed sound in the USA)and now ATC ( I’m the importer for both pro and hi fi for the entire US). I have the privilege of being able to ask an engineer who does driver design for living what’s what. My goal is as much for me as for my customer: the more you know the better, as most bad decisions in audio are made based on bad info or lack of info. There is a lot of misleading info posted on forums - this is what motivates me to post, to represent a different perspective, to represent what I know to be true.
You’re referring to a boutique element of high efficiency drivers that aren’t representative of this segment. Low eff. drivers have their expensive iterations as well, and when you count in the typically larger size of high eff. drivers, bigger voice coils and more magnet material, not least from the more widely accessible pro sector, their pricing compared to low eff. "hi-fi" dittos is actually very fair. Most of these very expensive high eff. drivers are vintage designs of limited production, btw., and it’s not that the production tolerances here are somehow magically "tighter" to reflect and account for the higher pricing.
Tidbit: just going by specs the EV woofers of my main speakers share the 97dB and 22Hz Fs TAD numbers of yours (Fs 21Hz, "broken in"), and I’m guessing they’d have retailed for about 1/10 of $4,000.
@phusisI think the power handling might also be part of the difference in price. My speakers also use a set of field coil powered 15" units, hand made by Classic Audio Loudspeakers that seem well north of the $4k of the 1602s.
Being few of these designs are vintage, or so I suspect, it hardly reflects a strict need for a particular driver-amp type adherence. My guess is many like for horn-based designs to be "toned down" a bit (tubes generally would seem to do just that) so to likely please a former habitual exposition to less dynamically/transiently capable direct radiating and lower efficiency designs.
Horns were used in the old days because tube amplifier power has always been expensive so you had to get the most out of the power you had. The use of controls on these older speakers clearly places them in the Power Paradigm.
I merely implied that context is paramount, and moreover suggested that what you advocate design-wise could as well end up being refuted (i.e.: the ears being the most important and last "judge" of things), not necessarily to say some people wouldn’t like the sound of your amps, but that they may prefer a speaker-amp combo that goes contrary to what you recommend :)
FWIW I'm one of the few that see a direct line between what we measure and what we hear. I'm of the opinion that the implications of what the measurements are telling us are not well understood so people still trot out the old saw of our ears being able to hear things we can't measure. So I'm of the same camp as Daniel vonRecklinghausen.
Moreover, the claim that high efficiency is necessarily and always bound to be attained "with a price," sonically speaking, is a fallacy.
Generally, high efficiency speakers have sounded unrealistic. What do the masses think of and come to conclusions when they’re thinking high efficiency? There it is, it can be attributed largely to bad actors like Klipsch, who’re all over the place and generally made plenty of flawed speakers with a couple of exceptions perhaps. It also seems like any other jester will come up with some horn speaker whilst tinkering in his garage, bring it to shows, etc and they’ve sounded stupid.
Nevertheless, when you buy a high efficiency speaker from guys who really know what they are doing, they seem to sound truthful. ...
Dear @ghasley : You say that prefers no negative feedback and maybe because you have a deep misunderstood on feedback amp issue but some of us can learn about in this link coming for a truly expert engineering:
Several years? I was with ADI- designing a wide variety of ICs for almost forty years and was most fortunate to become an ADI Fellow and Senior Fellow.
I am not a free-lance engineer. I retired from ADI a few years ago and I design audio (and other gear) for fun and for free, "
Sometimes post in Agon and is a gentlemans that we have to listen and read him. But as always are other people that just never learned due to their own or audio sale agenda, especially in electronics items.
Dear @lonemountain " most bad decisions in audio are made based on bad info or lack of info. There is a lot of misleading info posted on forums "
yes, but in the forums are many very good information ( not bad information ) where we can learn. I learned in this thread with several of the posts of gentlemans that have higher knowledge level in the specific regards that me and one of them is @phusis and other like them.
Btw, I remember listened 4-5 times in the past the original Wilson Watt and this is a fantastic true monitor not high efficiency as a horn but measured 91db and this Watt has a problem for any amplifier ( tubes forbidden with ) at 1khz its impedance surve measures 1ohm and near 2khz 0.32 ohm . IN those times the preffered amps for it were Krell and Spectral.
As a fact David Wilson made it all his Wilson Audio LP Recordings using in the studio the Watts and at Wilson place the WAMMs. I own all those fantastic recordings that are impressive: microphones by Sennheiser ( recordings in the late 80's ), Recorder by John Curl, cables by Bruce Brisson. We have to remember that DW before started in the speaker design was a recording engineer for several years.
Dear @daveyf : I think that in many ways the speaker impedance curve and phase is way more important than efficiency.
Almost no speaker manufacturer ( if not all of them. ) gives to the owners that speaker measured characterisatics and normally only gives the speaker " nominal " impedance.
With out those 2 characteristics how any speaker owner could mate in a " decent " way the amp for his speakers audio system?
The Watt had pretty decent efficiency at 91 db but those very low impedances happens in a very usual frequency range where MUSIC comes.
That's why several audio system owners are not satisfied with the speaker or amp or boths.
Very good point and great example that there is more to know about a speaker than a 1w/1m spec. Could a 86dB 1w/1m speaker with a very flat impenace curve outperform a 91db 1w/1m speaker with a wildy changing impedance curve? Yes.
@rauliruegas I think we need to be more clear as to what we are discussing when it comes to lower sensitivity. There is little question that a lot of great speakers are in the less efficient camp, meaning that they are not in the 100db/w mode, but closer to 85db/w etc., These very same speakers may drop down into the 3-4 ohm load in the bass, which might present a more challenging load to some amp designs, but like pointed out, with a sufficiently beefy power supply, will still work fine. These are not really the speakers that I am talking about here..
@daveyfThis makes more sense. Your original post seemed to suggest your dissatisfaction with speakers not efficient enough for “your” tube amp vs speakers that are inefficient way below the average speaker.
I’ve demoed many good/great speakers at brick n mortar and audio shows, but very few subjectively “resonated” with me. That’s why I thought it a good thing that the OP found such a speaker. Unfortunately, the speaker requires significant power. Maybe a tube pre + SS amp might work out economically and sonically. Good luck with your search.
Btw, I remember listened 4-5 times in the past the original Wilson Watt and this is a fantastic true monitor not high efficiency as a horn but measured 91db and this Watt has a problem for any amplifier ( tubes forbidden with ) at 1khz its impedance surve measures 1ohm and near 2khz 0.32 ohm . IN those times the preffered amps for it were Krell and Spectral.
This is mostly incorrect.
At the time this speaker was made, the national sales manager of Wilson was using Atma-Sphere OTLs in his home system. The Watt was an easy load for any tube amp (David designed his speakers using ARC amps and often showed with them; my first exposure to Wilson was at the ARC factory).
That 1 (or 2) Ohm load was at about 2KHz where there wasn't a lot of energy. The tweeter had a resonance problem and so there was a 2KHz trap that presented the amp with a low impedance, thus knocking out the resonance pretty well. This worked great with tube amps! Not so much solid state, as solid state amps would often make more power into a lower impedance rather than less.
Well , that large size is not exactly typically " because depends on the kind of drivers other than horns and an example are my ADS speakers that yes are " large size " but the size is due that the speakers can goes down to 16hz through two 14" acoustic suspension woofers but today I have the ADS from around 100 hz and up and the soft domes ( silk ) acoustic suspension 2" for the mid-range and 1" for the tweeter ( one a top the other:nearest as it can be. ) needs a very small " box space " due to its very high gauss magnets ( are not vented and non-ferrofluid. ) around 24k in the tweeters and 18K in the mid range, both drivers made it in Germany for ADS and its efficiency is 95db ( almost a horn . ). Unfortunatelly the drivers manufacturer just does not exist any more.
True 95dB sensitivity is certainly quite efficient compared to the general norm of speakers (that are closer to a typical 85dB’s, making for a ~10dB difference here), and in conjunction with your ADS L-2030 speakers extending as low as they do with dual 14" woofers per cab there’s no escaping the implications specified by one Mr. Hofmann and the following larger size.
My efficiency context is higher, and once horn-loading becomes necessary/preferred, not least when you want them to act like horns in their entire frequency span, up to very large size is unavoidable. In my setup context I’ve not yet fully exploited the efficiency factor (save for the midrange/tweeter horn); if I wanted at least ~105dB sensitivity top to bottom (i.e.: 20Hz-ish on up) it would require non-truncated front loaded horn subs and similar type horns for mid bass (but with the fewest and low degree horn path bends) or star quad 15" direct radiators, which is a significant upgrade size-wise below ~500Hz easily by a factor of 2 compared to what I have now. Having said that my corner mounted tapped horns subs takes further advantage of significant boundary gain (1/8 space), and so the least efficient driver section is the midbass bins sitting at ~98dB’s (hardly slouches, also considering they’re high-passed).
Trying to make some sense of the madness one could ask whether an efficiency that high is really necessary in a home environment. Obviously that’s up for each to assess and decide, but to me at least it isn’t about bonkers SPL’s; it’s about maxing out the sonic potential of horns and aiding the best integration, also with direct radiating sections. Ease of load of the amps, not least with active config., is another boon. Indeed sufficient headroom is a prime takeaway here (regarding both speakers and amps) - that is, it’s that it actually matters, and far more than people seem to realize.
What keeps most audiophiles (who’re already inclined towards high eff.) from venturing into very high efficiency and directivity control in the entire audio band - with all that entails - is mostly about large size becoming an obstacle, be that aesthetically or practically. However it’s also about a particular mindset, because it requires of one to acquire pro segment, DIY or vintage gear when such large designs are hardly available domestically, not least at less than astronomical prices. It’s a radicality of approach few (but perhaps more and more) are willing to pursue.
Generally, high efficiency speakers have sounded unrealistic. What do the masses think of and come to conclusions when they’re thinking high efficiency? There it is, it can be attributed largely to bad actors like Klipsch, who’re all over the place and generally made plenty of flawed speakers with a couple of exceptions perhaps. It also seems like any other jester will come up with some horn speaker whilst tinkering in his garage, bring it to shows, etc and they’ve sounded stupid.
Nevertheless, when you buy a high efficiency speaker from guys who really know what they are doing, they seem to sound truthful. ...
Very good point and great example that there is more to know about a speaker than a 1w/1m spec. Could a 86dB 1w/1m speaker with a very flat impenace curve outperform a 91db 1w/1m speaker with a wildy changing impedance curve? Yes.
That’s not really saying anything about the argument of high efficiency, in fact it goes without saying. Your effort to isolate a high sensitivity rating as a singular, non-determinant factor in no other context than itself is just trying to serve an argument against it, and not seeing it for what it can do in the greater scheme of things. Come on :)
Over the years I have found that lower power amps (35-45 wpc) always sound better to my ears. That makes low efficiency speakers (83-87db) a non starter for me
Well, D.Wilson ( paw, unfortunatelly. ) was not so stupid and " deaf " as his national manager and he used only Krell/Spectral amplifiers with the Watt/WAMM speakers to monitoring all his great Wilson Audio recordings.
"
The manual suggests that direct-coupled Futterman and similar tubed amplifiers are inappropriate, but gives the OK for other tube models when used on their 4 ohm tap. I have to disagree. A 1 ohm load severely limits the output power from a tube amplifier. For example, a 100W output (17dBW, 8 ohm) into a 4 ohm load will typically fall to 7dBW, or 10W in level terms, when faced with 1 ohm. Simply, this means that the amplifier will clip 10dB earlier if a strong musical signal appears at 2kHz, which is not unlikely, since this frequency is well in the main music power band.
Let us also assume a typical case where the tube output impedance and cable loop are limited to 0.4 ohms. Overall there is a loss of 0.8dB over the whole range, but at the 2kHz minimum impedance the loss increases to nearly 3dB, this inducing a dip in acoustic frequency response of 2.2dB which may well alter the sound of the speaker.........................................................Last and by no means least, there is the matter of that awkward load impedance, and the corresponding, almost unforgivable dip to 0.33 ohms noted on the review pair.......................................................Depending on the amplifier used, there was also a touch of hardness on, or edge in, the upper midrange which was ameliorated by using the Goldmund Mimesis 3 power amplifier and one or two of the other high-current amplifier types such as the Krell. This mid-treble problem was rather amplifier-dependent (due to the impedance characteristic...."
Btw, we have to remember that that 1 0hm and 0.32 ohm at those frequencies is not a discrete impedance value but part of the speaker impedance curve and the adjacent frequencies and developed harmonics are " touched " too.
Stupid people are all over the world and just fine with me.
My argument is that this efficiency as it relates to speaker performance is a complex issue, much more than a simple number. You forget I am engaged with dealers and end users who ask these questions (and similar ones) quite often. The desire to reduce a complex issue down to a simple one is very attractive when the subject is complex. THAT is my point, not that there aren’t times when facts are facts.
Since you own DH1A, I can use a historical reference: I bet you remember many people arguing the advantage of 1.3 inch throat driver/horns (EV) vs 2 inch driver/horns (JBL) and vice versa. That discussion was often reduced to focus on one attribute (throat diameter) when really it was a far more complex issue than that, depending on what you were trying to accomplish.
Dear @phusis : " Indeed sufficient headroom is a prime takeaway here (regarding both speakers and amps) - that is, it’s that it actually matters, and far more than people seem to realize. "
Normally audiophiles do not cares enough about " headroom " eve3n some of them not even know what it means in electronics and especially when we are talking of speaker/amp combinations.
As a fact I learned through my first hand audio experiences when I owned thr Classé DR3-VHC This amp is a pure Class A design with a power of " only " 25 watts but in its times was only one of the few amps that handled with aplomb the Apogee Scintilla that gone even lower than 1 ohm impedance and with not high efficiency but around 79db at 3m. but ( if I remember the Classé came with 7db on headroom and from here its VHC denomination: very high current. ).
Its very important to some so much so that they house giants. Its also of very little importance to some so much so that they house giant amplifiers. If you don't want high power it would be important to you.
@lonemountain Brad, I think one of my points is that the free choice of speakers and amplifiers are connected. IOW, a highly inefficient speaker is going to severely limit your amp choice, and conversely a very low powered amp ( or an amp with minimal current drive capability) will also be a non-starter with a speaker that cannot be properly driven by said amp. Therefore, picking out either one of these designs invariably leads one down a path, that may or may not be where one wants to go.
One of my points is that this very issue of "what amp is enough?" is based around very fuzzy poorly defined/poorly understood info about speaker efficiency, Would you call a 90dB SPL 1w/1m speaker efficient or not?
@lonemountain Brad, you make an interesting point. While most folk would consider your example as efficient, the other variable, which could effect how an amp interacts with this speaker is how the load the speaker presents varies across it’s frequency spectrum. For example, I know of a very good metal box speaker that has specs similar to what you post ( not quite as good, about 89db vs.90db), but this speaker drops down to less than 1 ohm in the bass regions between 35hz and 55hz. Therefore, I’m not so sure I personally would consider this speaker as an efficient speaker, or easy to drive.
Asking the question "What is efficient enough?" brings up mutiple challenges. the first being hardly anyone listens much over 90dB SPL!
I was at AXPONA this weekend and in our room we are demong ATC. I meassuredIf the SPL when things got "loud" : it was around 92dB SPL. If the 1w/1m spec of a passive was 90dB, it would require less than 2 watts to get that speaker to play at 92dB 1M. If it was 86dB 1w/1M it would require 4 watts to get it to 92dB at 1M! 92dB SPL is very loud for many of us, most audiophiles wouldnt even want it at 90-92dB SPL in their living room or listening room.
It appears in reading this thread that most would agree that above 90dB 1w/1M is efficient and 86dB 1w/1M is "not efficient". We need 2 watts to get our 86dB speaker to 89dB SPL, which is indistinguishable from 90dB to most of us. This 2W instead of 1W is really a critical issue and one that drives a purchase?
My point is that very very few of us listen at 92dB SPL. The argument for an "above 90dB 1w/1M speaker" is not a relevant argument as no one even wants to listen that loud. 90% of our listening is WAY under 90dB SPL. If this is true, why is 90dB+ 1w/1M efficiency such a important spec that we all need to pay attention to it?
I meassuredIf the SPL when things got "loud" : it was around 92dB SPL. If the 1w/1m spec of a passive was 90dB, it would require less than 2 watts to get that speaker to play at 92dB 1M.
? Only if your listening distance is 1 meter....SPL drops by 6 db, every doubling of listening distance. If your listening distance is 13 ft, a 90db (1meter) sensitive speaker will produce 78 db avg at your listening position (13ft) with 1 Watt of power.
Headroom and the variables that play into it is a debated topic and it will tend to dictate higher powered amps. Higher powered high fidelity amps could get expensive.
P.S.
Take a SPL meter with you to nightclubs, concerts, discotheques, etc. When you’re really enjoying the beat (having fun), take the SPL meter out and you will often note that it is higher than 90 db and a lot more...Or just go watch an orchestra. You’d be surprised at what your db meter reads.
Asking the question "What is efficient enough?" brings up mutiple challenges. the first being hardly anyone listens much over 90dB SPL!
Brad,
As you’re no doubt aware of, comparing lower efficiency speakers with true high eff. dittos isn’t an apples to apples scenario. It doesn’t only come down to how loud one enjoys playing the stereo, but rather and not least how a given volume is reproduced - i.e.: the very nature of the sound. Many aspects come into play here, like speaker principle/driver types, directivity pattern, headroom (or lack thereof), cone area and overall physical size, specific design choices, etc., and these aspects can be a product of or otherwise relate to a given sensitivity, which again has sonic implications. Choosing high eff. speakers can’t help but reflect on these interdependencies, and thus speaking of and preferring high eff. speakers doesn’t really revolve around a numeric sensitivity value in itself - certainly not as an isolated parameter and choice alone. That should be pretty obvious by now, I’d say.
I was at AXPONA this weekend and in our room we are demong ATC. I meassuredIf the SPL when things got "loud" : it was around 92dB SPL. If the 1w/1m spec of a passive was 90dB, it would require less than 2 watts to get that speaker to play at 92dB 1M. If it was 86dB 1w/1M it would require 4 watts to get it to 92dB at 1M! 92dB SPL is very loud for many of us, most audiophiles wouldnt even want it at 90-92dB SPL in their living room or listening room.
That’s a very crude outline of what’s actually required power-wise. Many low eff. speakers at actual listening distance will be closer to their limits or lacking noticeable headroom at 90-95dB’s than one imagines, and moreover you have to factor in the girth of passive crossovers and their varying degrees of load-strain on the amplifiers; a 100W amp may be brought to its knees with a passively configured speaker long before those 100 watts are actually converted into an SPL that truly reflects the theoretical outcome at the listening position in relation to the rated(!) speaker sensitivity. Seems to me you’ve become a bit spoiled dealing with active speakers mostly, as well as drive units that are anything but representative of the general range of hifi speaker drivers ;)
It appears in reading this thread that most would agree that above 90dB 1w/1M is efficient and 86dB 1w/1M is "not efficient". We need 2 watts to get our 86dB speaker to 89dB SPL, which is indistinguishable from 90dB to most of us. This 2W instead of 1W is really a critical issue and one that drives a purchase?
While, all things being equal, a 85 vs. 91dB sensitivity difference isn’t trivial, the latter isn’t high efficiency by any means, period, irrespective of the general gist around here. Relative to 85dB sensitivity it’s certainly a higher number, but that’s just about as far as it goes. Keep wandering in the low to moderate efficiency spectrum however may make for a more convenient outset to discuss low vs. "high" efficiency, as it appears to keep the speaker principles within a more manageable and homogenized sameness, and thus a numeric sensitivity value varying 5-7dB’s is mostly what it comes down to here, not that it can’t be a deciding factor with regard to amplifier choice, a sense of headroom and max. SPL.
Comparing low efficiency speakers with true high efficiency dittos (>97dB, or thereabouts) is another matter though. Here high eff. mostly involves horns, compression drivers and larger diameter woofers, as well as larger enclosure sizes, and this has sonic implications for a variety of reasons, as I implied above.
My point is that very very few of us listen at 92dB SPL. The argument for an "above 90dB 1w/1M speaker" is not a relevant argument as no one even wants to listen that loud. 90% of our listening is WAY under 90dB SPL. If this is true, why is 90dB+ 1w/1M efficiency such a important spec that we all need to pay attention to it?
So, what you’re saying is that people buying high sensitivity speakers effectively and essentially has an excess of efficiency that isn’t of any use, unless very low powered amps are sought? When this speaker segment may often be referred to as having excellent dynamic capabilities, sense of power, scale, ease, etc., do you think that only pertains to SPL’s above ~90dB’s? And even if it does (in peaks), isn’t that relevant to some of us? And what about these traits (and others) specifically - are you going to tell me they aren’t partly related to higher sensitivity, with all that entails?
Scroll to about 5:50 and onwards on this Levinson demo...These are about 100db/1W/1M pro audio style of speakers. The demo is at @110+ db. This is the type of speaker that starts to laugh at all the Harbeths, panels, etc. No orchestra ever came home full tilt with the latter type of ’speakers with challenges", in comparison. But...for "Female Vocals" @ 65db (nap time)?? Ok, sure, anything and everything works for that stuff...comes down to your listening preferences.
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