most accurate loudspeakers....

Many of you are correct, it is personal choice and your own ears. Now that being said ,I do agree with Stevecham in that Thiels are incredibly accurate and one of the best
loudspeakers I ever heard was a Thiel CS 7.2 my ears that is.
if you mean a 'flat response throughout the range' there are are too many models (try hundreds)to name them all. i suppose over several decades, AR hit the mark as many times as anyone, and early on, wrote the book.....on the other hand, nothing sounds more like a real trumpet, than a trumpet played back through a klipsch of nearly any model, new or lets start naming the hundereds of others....
Duntech and Dunlavy claimed to build the most accurate loudspeakers, and had a large number of measurements of different parameters made in anecholic chambers to back that claim up. In-room they, as all speakers, might deviate from neutrality, but they always were (and still are) remarkably coherent and neutral speakers.
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It depends on what you mean by "accurate."
A good place to start is to check out what most of the prestigious studios and mastering engineers like to use. Full range accuracy at both low level and realistic live sound levels is actually quite rare in home hi-fi.
Viridian- I do like your thinking. If my man isn't to remote, he should go to dealers in his area toward the end of the week and see if they won't let him take home and audtion over the weekend. The latest Merlin monitors are getting a lot of press about their "accuracy". Their acoustic suspension designs as opposed to ported so their bass may be tauter and with better timbre than the latter designs but with less abundance. The word accuracy makes me think of Dynaudio, as well (Contour series and up). Chances are, my man may not know what's gonna groove him the most. In home auditions are the way to go.
the phrase "more accurate" is an oxymoron. all speakers are inaccurate. accuracy is dichotomous. there is a state of accuracy and a state of inaccuracy.

one can use the phrase less inaccurate to indicate a state which is closer to accurate, i.e., perfection.

as has already been said it is difficult to quantify inaccuracy. it is possibly to provide measurements of various parameters. then what ? how do you quantify accuracy, given measurement statistics ?

why not consider which speakers are most resolving, if that is your goal ?
My personal quest has been to find speakers (with ancillary equipment) that do the best job of placing me in the same space with the performers. To create this illusion of reality is devoutly to be desired but is impossible to achieve completely. One's listening room must either be removed from the equation or tailored to reinforce/tone down anomalies. I guess what I'm trying to say is that the minute you place accurate speakers into a listening room they are no longer accurate sounding.
Do we agree that it is less inaccurate if the speaker doesn't intentionally remove harmonic content by inverting the phase of the midrange relative to the tweeter and woofer? This "band aid" is used frequently in design by some of the most "prestigious" manufacturers in order to attempt to compensate for high order crossover anomalies.

At the very least do we agree that speakers should first minimize doing any harm to the signal they are fed? If so then why would we be interested in any speakers that intentionally, by design, actively "damage" the harmonic content of complex timbres that define voicing of various instruments and voices? Even electronic instruments that can be recorded and reproduced through the electronic chain as accurately as possible will suffer in this regard if harmonic content, complexity of overtones and timbre, are altered by intentional attempts to "correct" problems inherent in the electrical architecture of a speaker.
Dear Beemerrider,
I totally agree with you. The room and the speaker system have to be one organism. You cannot have one box playing in another box and hope for accuracy. You will only get higher and higher levels of audiophilia in conventional audio, but not accuracy. My two bit, if ever any of you go to Denmark, check out the SLT monitoring system in Focus Recording( studios.
Active ATCs or PMCs. Take your pick.
Another way to ask the quesion is, which speaker reproduces the analog signal with the least amount of change? How would you know?? It's all relative isn't it? If you listen to two speakers on the same system, you may think that one of the speakers produces a voice more "accurately" but, how would you know?????
It's easy to define accuracy, hard (impossible) to achieve. Compare the waveform going in to the waveform coming out. The closer the output is to the input, the more accurate the speaker.

Many factors are involved in accuracy. All forms of distortion, harmonic, intermodulation, linear, phase, time. Not all forms of distortion are equally audible or important from a psychoacoustic standpoint. Other factors include, the stored energy of the drivers, the cabinet resonances, refraction, and interference patterns.

Room variations and anomolies must be eliminated for a true measurement. But, of course, the room comes into play for the user. This brings up another factor, power response. How does the speaker 'light up' the room, and how well does the ambient sound field correspond to the direct sound? Speakers can measure very well on axis, and create a miserable sound field that colors everything.

These factors also need to be prioritized. Suggested priority:

1) Linear response
2) Harmonic and IM distortion
3) Stored energy
4) Power response
5) Phase and time
In my opinion the goal is to recreate as closely as possible the illusion of a live performance, and this implies taking psychoacoustics into account. Just because something can be easily measured doesn't mean it's relevant. If low-order harmonic distortion is inaudible, then an impressive-looking measurement in that area is irrevelant.

To give a more common example, as long as we measure the on-axis anechoic response but listen to the power response, there will be a disconnect between frequency response measurements and subjective perception.

Following this line of thought, the most accurate loudspeaker is the one that comes the closest to reproducing the perception of a live performance. We don't presently have a metric that accurately predicts subjective preference - indeed, the audio industry has thus far resisted the adoption of such a metric presumably because there would be far more losers than winners among manufacturers. What we'd need is a psychoacoustically-weighted metric that takes into account the relative audible significance of everything the device does to the signal (the "transfer function).

Of course I have my opinion as to which characteristics are likely to result in a speaker that closely approximates the perception of a live performance, and frankly some of these characteristics are unlikely to show up in published measurements. Among these obscure characteristics that I think matter are dynamic linearity (lack of power compression or at least uniform power compression across the frequency range) and radiation pattern smoothness (related to but not the same thing as power response).

I don't know of any speaker that really "does it all", but my personal leanings are generally towards planars and horns rather than direct-radiator dynamics - even though the latter are more likely to produce impressive-looking conventional measurements.

Reference 3A is the most pure by far ,if you know what a real instrument sounds like then one listen and you
will know. The critical Midwoofer driver is completely made by hand in house the tweeter is far better then the stock ring radiators out there If your electronics are not bleached out like Naim for instance than go out of your way
to locate a dealer .
no speaker is accurate, period. most speakers state their frequency response within 3 db. that is not accurate.

at best one can a speaker is less inaccurate than another.

a speaker is either accurate or it isn't. it can't be incredibly accurate. it can't be slight;ly accurate. it is not accurate and not perfect.

there is no way to assess a speaker's accuracy. there does not exist a definition of accurate nor a way to objectively measure or calculate an inaccuracy score.

since we are expressing opinions, i would say the quad 57 is the least inaccurate of all speakers, within its range.

the thiel speakers sound top heavy, i.e., peaky in the upper midrange/lower treble.
Most of the producers and big studios use ATC while they record and mix. For home use I believe they are toooooooo flat. No salt, no sugar, no spice. Simply flat. But professionals like ATC because they give them confidence for the final product. For ex. Pink Floyd used ATC for all their recordings and band members use ATC in their homes.
I would vote for any speaker that:

(1) Has ruler-flat frequency response, at all power levels;
(2) Is completely phase coherent, at all frequencies and at all power levels;
(3) Has a completely resistive load at all frequencies, in order to present an entirely benign load to any amplifier;
(4) Has very high sensitivity, so "detail" is not lost at low SPLs;
(5) Does not interact with the room.

Trouble is, this is impossible with current technologies. Closest you'll find is an actively biamplified line array with a DEQX.
ATC and/or PMC are anything but flat and accurate. One more myth that some clever marketing guys had manage to sell the public. If you look at the history of ATC you realize why it is popular in studios. It has nothing to do with the way they sound.
If you look at the history of ATC you realize why it is popular in studios. It has nothing to do with the way they sound.

Perhaps it is the way they look - such aesthetically elegant black boxes the likes of which few have ever seen!

Perhaps they are so heavy that they are harder to steal than the wonderful sounding Yamaha NS-10's ;-)
Perhaps, but it was mainly the fact that they can play loud and not break. You know, like typical PA speakers.
Perhaps, but it was mainly the fact that they can play loud and not break.

Agreed but isn't that what accurate reproduction is about? The 120 db dynamic range of our hearing! Many unamplified instruments have huge dynamic range, which means they can go very loud indeed - especially transients from percussion and from wind instruments, such as horns.

There is a plethora of good speakers that can perform extremely well up to about 100 db SPL (most with mass-produced Northern European drivers), you know, Typical Hi-Fi Speakers.
Well loud yes but at what distortion level? A car horn can produce a 120db tones anytime. That is why you do not use PA speakers in your home. There is a big difference between the need to simply amplified and the need to accurately amplified. And when I say accurate, I mean liner FR and low distortion. Two things that PA systems are not very good at.
Roypan -- the measured distortion levels produced by ATC at high spl are comparatively low (unlike many PA systems). That's actually a useful thing.
Gregm- I have my doubts. The only independent measurements I have ever seen of an ATC speaker were not very impressive. On the contrary. The distortion levels of their dome midrange was completely unacceptable (Stereo Sound issue 155).
I must say, that to my ears, that is how they sound as well. Especially when driven hard. They get harsh and glossy sounding as soon as you push them.

I have not seen the plots you refer to so perhaps you could PM it? Your observation that ATC powerful mid domes can sound harsh when driven hard is a fair one. ATC claim IM distortion in the inner ear affects hearing at extreme levels (could it all be marketing hype as you suggest - I don't know). What I do know is that they sound too harsh on certain recordings like Green Day and other hyper compressed modern CD's (ONLY when played extremely loud of course). Bear in mind, that it is principally the dispersion pattern of a dome mid which is desirable and not low distortion levels. It is well known that large dome mids are difficult to build with distortion levels as low as regular cones - ATC actually uses two suspensions to help maintain VC alignment.

So playing loud while maintaining accuracy/linearity similar to what can be achieved quite easily at low level, as you point out, is extremely difficult to achieve (exponentially difficult in fact). This is why most cheap headphones are very impressive in linearity and distortion figures compared to speakers! This is why there are a great many excellent speakers that go up to 100 db SPL.

Incidently, your Magico's apparently use constrained layer damping in the mid range cone. I read somewhere that ATC is doing this too on their entry line...lighter cones, smaller motors and yet well damped...a recipe for good sound to me! I must admit the Magico V3 sure looks impressive and the Ultimate is so extreme I doubt I'll ever see one let alone hear one! You could do us a favor and post pics of your Virtual System as I bet it is accurate ;-)
Seems to me that if someone has come up with the "most accurate" or "least inaccurate" speaker that all would follow and we would have one universal speaker. The truth is IMHO that the degree of accuracy or inaccuracy is measured - after all is said and done - by the ear. For every criticism there is a positive review somewhere. How could we ever find common ground on this issue - unless you choose Maggies!! LOL
Shadorne - Thoughtful reply. Thanks. I think that it is difficult to keep IMD down with any “soft” dome. You are practically operating in a non-pistonic way. Not ideal for “moving air”. Yes the dispersion of a dome mid is very nice but it takes more to tango. The MAGICO’s do use an incredibly stiff, yet well damped, cones. The dealer had a cone on hand to demonstrate how he can stand on an 8 grams 6” cone and not break or bent it. Very impressive. I have notice how easily you can push the V3 to dangerous SPL without realizing it. Clear sign of low distortions. I got to watch out, my wife claims I am losing my hearing… One of these days I will post my system up. It is always too messy to photograph. Not too fancy but I think that if nothing else, linear with very low levels of distortion.
There is an old comparison of ATC-300 and Dunlavy something here. If I were to stress the point, I would agree that there is some irregularity at the upper mid region at high spls; maybe that unit is somewhat stretched, or the cross to the tweet becomes iffy at very high voltages that don't seem to affect the woofs in the same way.
The dealer had a cone on hand to demonstrate how he can stand on an 8 grams 6” cone and not break or bent it. Very impressive.

That is amazing!

Light weight rigid cones are very attractive for rigid "piston' behaviour. The ability to control them with a small motor makes them very efficient, however, the issue then becomes one of managing the bell-like ringing rather than break-up. Soft viscous dense damped woven materials whilst less "pistonic" dampen this ringing at the expense of higher cone weights and more massive motor structures and a more limited frequency range before they "break-up"....a trade off if you like that results in inefficient drivers with narrower frequency ranges. Some materials/geometries provide a good balance for damping with both light weight and low cost - such as polypropylene woofers.

Another issue is beaming - this causes a reduction in the power response in the upper mids (even if on axis is ok) and will make a speaker sound less harsh at elevated levels. 6 or 7 inch cones are less well suited to upper mid range frequencies but 3 inch drivers, which are better for upper mids, suffer in generating the necessary SPL's at lower mids due to the large amounts of travel required and the difficulty in maintaining alignment on a small structure. Some speakers use two mid range drivers to help overcome this issue in a Dappolito arrangement. Some will simply accept to take a dip in the mids at elevated levels. Some will crossover the tweeter lower to limit the beaming but then run into tweeter compression issues at elevated levels (again a dip in the upper mids).

It is all a balance of compromises at the end of the day. So while I agree that pistonic is ideal in some ways it is another design factor in the grand scheme of things.

The MAGICO constrained layer damped cone is what impresses me most as it apppears to use a sandwich of rigid pistonic material constraining a viscous layer in the middle which acts to dampen the ringing (it shears when bell-like behaviour occurs in the outside rigid materials). Finally, an extremly rigid pistonic cone that may not suffer from too much audible out of band ringing. It may not address beaming from cones but it will likely be extremely linear and low distortion (accurate) particularly on axis.
I agree with Rcprince-Dunlavy's are ONE of the most accurate speakers make around. Of course in used market since the Co went out of business.
I agree with Rcprince-Dunlavy's are ONE of the most accurate speakers make around. Of course in used market since the Co went out of business

Agreed. Duntech Sovereigns are tremendously well respected, as are the V's.
Most of the producers and big studios use ATC while they record and mix.>>

where did you get this idea?

I don't find them flat actually, i find them less detailed in the midrange than some speakers. But, whatever someone is used to works. A LOT of records were mixed on altec 604's after all.
i have yet to be in a studio big or small and seen 'any' post work on 'any' audio track done with anything that resembles something considered 'audiophile'.....the 'room' must truly be the thing, and the mixes (and opinions) from engineer to engineer are as varied as opinions on this thread. the shear numbers would suggest that jbl dominates professional circles, but once again, what's used in the studio is just playback for whats already tampered with and altered anyway.
i have yet to be in a studio big or small and seen 'any' post work on 'any' audio track done with anything that resembles something considered 'audiophile'.....the 'room' must truly be the thing, and the mixes (and opinions) from engineer to engineer are as varied as opinions on this thread.

Quite true. Some studios, such as Crystalphonic cost five MILLION dollars - so there is no way they resemble a home Hi-Fi!

However, many sound engineers are not beyond the semi-religious kind of simple tweaking and attentioin to minor details that is normally associated with audiophiles, such as what an amp sits upon, or what kind of wire runs between a woofer and an amplifier!

So I don't think you can dismiss this group, if anything they are surely more discerning buyers than people who have a day job and come home to their system only in the evening/weekends. Here is a great example of the use of Shakti pads, Van den Hull cable rewiring of speakers and many other tweaks that highly respected sound engineers get up to on a the sailor said quote, "Now ain't that a hole in the boat"!
How do we define most accurate? Here are a couple possibilities:
1. Most accurate at creating the illusion of a live concert or musicians in your home?
2. Most accurate and reproducing the input signal's waveform in room at your listening seat?

At this time I believe these 2 possibilities are mutually exclusive.

I know some speakers that do a good job at #1, like Sound Labs. I don't know ANY speaker which can do #2.

Donald North
the problem with a subjective criterion like the illusion of a live concert is the wide range of assessments associated with a given stereo system.

the pursuit of accuracy, the measurement of accuracy and the criteria for accuracy are all counter productive.

if i can say i like the sound of a stereo system it doesn't matter how inaccurate it is.

the question for all of us, why do we like the sound of a stereo system ?
"Why Is There Air?"
-Bill Cosby, 1965
The first and last speaker to fool me I was listening to a live performance is the Apogee Scintilla. No other system, in any room has come close.

That moment when I walked into an audio store, where I had listened to scores of speakers, I heard a piano being played - in the near vicinity - I literally walked all about the store looking for the recital.

I completely agree with Donald. You cannot have both and I prefer the first possibility he's mentioned. I would only add the old Quads to his Sound Labs.
I would agree with Donald & Detlof above, and raise the following point: an "accurate" speaker-system is capable of creating a NEW musical event in the room, BASED on the original recorded event."
This is just an attempt to paraphrase or review Donald's No1.

Good point. I think that
an "accurate" speaker-system is capable of creating a NEW musical event in the room, BASED on the original recorded event."
is a nice way to put it.

I also think that Donald's statement,

1. Most accurate at creating the illusion of a live concert or musicians in your home?
2. Most accurate and reproducing the input signal's waveform in room at your listening seat?

At this time I believe these 2 possibilities are mutually exclusive.

is so true of the majority of HI-FI today. Sadly the pursuit of sizzle and hyped sound in order to differentiate and impress has left people feeling that the above are mutually exclusive goals. Either you get an atmospheric warm lush sound with little accuracy in timbre and poor dynamics or you get a clinical and dynamic sound with the tiniest sweetspot and with music so unnatural sounding that it feels like it has been torn apart or dissected, even if it is exciting because of the impact.

However, I strongly believe that THE goal is to strike a healthy balance.

A large sweetspot with an even and natural sound field coupled with precise timbre and realistic dynamics.

Aristotle would describe this as the "golden mean". A "Goldilock's System", where everything is just right and balanced; natural in tonality, timbre, dynamics, accuracy AND acoustic sound field.

The blind pursuit of any single passion, such as a holographic image or deep lush bass, generally comes at the expense of other virtues in a system. It soon becomes tiring and the gear "merry-go-round" keeps on turning...
Once in a while, I get the magic of realism. This is a fragile experience affected by the recording, probably the quality of electrical service, and even my sensitivity at the time. I know that speaker positioning, room treatment, breakin, stability of the cabling (not having been moved), etc., but when nothing involving these has happened, there seem to be some times when everything is "right."

I did not have the magic moments in the past which suggests my system has improved. I guess I need to concede that good speakers are part of this improvement, although I really think that speakers have improved very little in the last 40 years.

I do seek the idea of my system providing a musical event in my room. I want to at least have the "magic" of thinking I am at the recording event. If this is the definition of an accurate speaker, that is what I want. I do certainly agree that all speakers are compromises. Over the years I have recognized that it is the leading edge of the music and its dynamics that most pleases me. I like light weight diaphragms and high efficiency which really only leaves horns, but I also hate crossovers! This is why I got so excited about the new Feastrex full range drivers, only to realize that they are still a work in progress. What I would give for a 20 Hz-20K Hz, single driver, 103 db efficiency speaker!
The first and last speaker to fool me I was listening to a live performance was a tri-amped pair of Tannoy 215 DMT II that were being used as the main playback (not mixing) monitors in a recording studio. No other system, in any room, has come close. Of course, the studio had probably spent as much on acoustic treatment of the room as on the speakers (which used to retail for $9K/pr.).

Dr Joe,

Tri-amped Tannoy 215 DMT's that would be impressive! Where did you hear these?

By main monitor, I guess you mean these were permanently installed (in walls?) and mainly used to impress clients...
In my opinion Kharma speakers are the most accurate speakers on earth!