Anyone familiar with the Manger driver?


Sounds like a new and innovative approach to a speaker design. The big question is, HOW DOES IT SOUND? Some interesting stuff on their website MANGER, but I'm curious to know the impressions of people who have actually heard one...I didn't make it to the CES this year.
fatparrot
Hi Fatparrot,

I have heard the Manger driver sounding GREAT depending upon how it is used within a particular speaker design.

Best,

Barry Kohan
"I have heard the Manger driver sounding GREAT depending upon how it is used within a particular speaker design."

YES!! I have also heard the Manger driver sounding mediocre depending upon how it is used within a particular speaker design.

Kal
It's a wide-range driver and, depending on the application, it can be used down to 300-200Hz. It has an unusual sound; in some respects it's reminiscent of a ribbon & in others of cones. DIspersion characteritics are also somewhat unusual compared to a conventional cone. People who have tried working with it (N Pass is one of these) have had difficulties in getting the speaker system dispersion pattern right (among other things). The side firing mangers seen in some systems are purportedly there to smooth response from ~2kHz downwards...

I forgot: it's also an expensive driver so, if you're thinking of a diy scheme, check out a discussion at diyaudio.com. E-speakers sells it in the US and has some specs at the site.
Israel Blume of Coincident did a design with a Manger a few years ago. As I understand it, it never really made it past the experimental stage, with only a few examples produced. A friend of mine has one, and I've heard it a few times. It has a number of shortcomings that would make it unacceptable for me, though he loves it. To me it lacks immediacy and dynamics, though how much of this is due to the Manger and how much is the fault of the rest of the implementation (or even the fact that he doersn't play them loud enough) is impossible to say.
If he doesn't respond, you might contact member Plato, who had a speaker using this driver in his home a few years ago.
I've heard them in two models of Overkill Audio speakers at CES and T.H.E. Show. Both implementations were quite expensive (One model is $70k, including digital crossover and amps). The Overkill speakers sounded incredibly fast, dynamic and exciting. They also sounded quite musical and not as hard and metallic as many other very fast and loud speakers can be. I really did not have a chance to audition it they way I would if I were considering a purchase.

The obvious downside of the Manger driver is a very limited dispersion of highs. Even moving one's head just a few inches makes a big difference. I suppose good dispersion of highs is asking too much considering that the Manger works down to an extremely low frequency and looks to be bigger than 6" in diameter.
Larryi the Mangers are 8" (they do look small). But yr comments still apply!
Hi Everyone,
We have been working hard on our Overkill Audio loudspeakers and now are preparing to launch the Encore (not the prototype that was illegally sold by Joe Shanaphay or "bearman") which is the ultimate Manger equiped speaker.
Our new USA distributor will have his full reference system installed in March 2006 and then be able to demonstrate what can be done. Even if you are not currently in the market you will always be welcome to bring along your CD,s and have a coffee and enjoy the music!

All the best

Derek Wilson.
As the US distributor of Manger, some additional clarification re: the Manger driver, especially the range and crossover points...

1. The Manger driver actually has a bandwidth of ~ 85-35khz.

2. In the Swing model, the crossover to the Subsonic subwoofer is ~ 90hz.

3. In the 2-way Zerobox 109 stand mount using a custom Scan Speak 8", the crossover is at 140 hz.

More info at http://www.tmhaudio.com/Manger.htm

Jim Ricketts/tmh audio
Ooops, bad link. Try this one for more Manger info and specs....

http://www.tmhaudio.com/Manger.htm
7 years ago I built an active DSP based Manger system with a custom Scanspeak driver (not the paper one manger uses, yech). And it was righteous. Imagine Sound Labs U-1's with clarity and bass...you get the idea.

Manger driver is like a formula one racecar, the average guy can't drive it at all, a really good driver can keep it on the road and only the best can get the best from it.

Being speaker designer isn't enough to make a Manger speaker, and as Pass proved an o.d. on amp experience won't get you over the hump either

Gotta be able to do all three Speaker, Amp and DSP or you're not going to be good enough.

Kudos to Overkill for surpassing all the wannabee failures with the Manger. (70K? I'm still buying a Rocket Chassis 358 WOO late model for that money) Get much prettier girls from the same investment. :)

Manger with DSP is easily one of the ultimate home speakers, with Warner Imaging amplification on my original project and finding the right midbass driver can be brilliant. Sweet lightning.

Shame on me for never building another Manger Project...the allure of Diamond midranges from Accuton are very irresisteable and sucking up all my project money.
D_edwards, I neither understand nor agree with your remark, "Imagine Sound Labs U-1's with clarity and bass...you get the idea." Have you ever heard Sound Lab Ultimate-1s? And if so, under what conditions and how long ago? I purchased U-1s several years ago, later to become a Sound Lab dealer, and I can assure you clarity and bass have never been lacking, in fact they are some of the strong points. I suggest anyone who has heard U-1s properly set up would say the same. That is not to say the Manger drivers do not have their merits, but your argument citing U-1s as an example doesn't hold water, in my estimation.
Well EssentialAudio I have to ask based on this comment, cause I am assuming you actually know something technical about audio gear not just brand names.

"That is not to say the Manger drivers do not have their merits"

Like what? What are their "merits"? You should be able to rattle 5-6 things that make the Manger unique.

I cannot write an experience for you but no SoundLab is ever going to win an award for clarity, not with the reverb off the back wall (100% distortion), and when you can get 110db out of your speakers at 30hz call me, cause that is bass output performance commiserate with a $30,000 speaker system in my estimation. Just don't break anything trying, its not that important. :)
D_edwards, can you describe your Manger application -- the speaker part, the dsp part is obvious? BTW, that 10' paper scan is not a bad driver in & of itself.
What did you use?
Cheers
Hey Greg,

My Manger project utilize 2 dual voice coil Scan speak 8" Kevlar (100watts per driver perside) and twin tower 2x15" JBL woofers (total of 4).

Manger and paper allow for an easier passive crossover but the paper is a distortion liability in higher performance systems, and with Accuton and Seas using very rigid cones and better motors today, the speaker could be significantly better than what I built, waaaaaayyyy better.

That's not to dump on a Zerobox 109, 107, there are many speakers inferior to it, but in my opinion if you're not using advanced DSP methods, then you cannot get the best from the Manger driver.

The Manger driver today looks to perform about 70% better than the one I used, the DSP was used to control dispersion in the high frequencies and flatten the response to with +/- .5db throught the mids, with todays computing power the transparency of the DACs, the Manger can be realized to its fullest potential. I know why I stopped using the Mangers, but it appears those issues have been smoothed out and have become stabilized.

BTW, there's is nothing obvious about using the Manger, it was not like I bought the parts and the next day I had a speaker that was good and was on the U-1 level, more like 2-3 years later. You don't slip this driver in and suddenly you're a speaker design genius, infact its quite the opposite. All sorts of little nasty surprises that on other speakers could be ignored but are revealed by the superior performance of the Manger, simply cannot be overlooked. The Overkill guys would likely have even better stories and maybe some measurements. I have no records of my early projects and I can't even remember who I sold the system too. Some guy in Frederick Md.

BTW, you better have the "right" amplifiers, Nelson Pass does not make the "right" amplifiers for the Manger which is why he couldn't get it to fly. Manger is a tricky beasty that on paper looks like a plug and play miracle.

it is a trap. :)
My Manger project utilize 2 dual voice coil Scan speak 8" Kevlar (100watts per driver perside) and twin tower 2x15" JBL woofers (total of 4).
Now that's what I'd call refreshingly serious stuff!!
I assume the Scan was a 8546 - but w/ dual VC -- filling in midbass b/ween Manger & JBLs?

Actually, a contemporary Manger I tried briefly has a smooth pattern in the mid/upper-region (s/thing bumpy ~7kHz, never figured out what it was).

Thank you for the descrip.
Hey Guys,

A bit of updated info re: the Manger driver.

Daniela Manger has indeed further refined the driver which is now quite linear in response and impedance. Much easier to drive and achieve even more spectacular results.

Now the caveat, since the driver is lightning fast, an amplifier that can keep up is optimal. However, superb results can be obtained with many amplifiers out there on the market. Contact us if you have questions about a specific model.

I have always preferred what ESL, Ribbons, etc can do well and I find similar qualities in the Manger. And without the physical size and required room dimensions. Even the 2-way ZeroBox 109 (19" tall) with the 8" ScanSpeak carbon-bass driver that takes over at 140 hz is extraordinary. The 109 puts other much more expensive loudspeakers to shame in all the audiophile areas and yet sounds so naturally real & live.

More info at http://www.tmhaudio.com/Manger.htm

Jim Ricketts/tmh audio
No problem Greg,

As for the dual VC Scanspeaks, never saw anything like them before or after, I bought 6 from Madisound, used 2 in a car stereo system and the 4 in the Manger system.

Must have been ordered by a manufacturer and it didn't work out etc.

BTW TMH,

Anytime you want the best amps for the Manger's, I can get them for you. Will absolutely blow your mind and the cost about <$4000 retail 3 channel and to be honest no money will get you much better. :) The designer will build them (OEM) in your name if you like. Just design the faceplate and poof TMH Audio amplifiers.
D_edwards,

Thanks for the info re: the amps - feel free to send to me jim@tmhaudio.com

But I must say our Metronome Class-A mono amps (AMT-70 and AMT-140) are fast, ultra-wide bandwidth, detailed and so clear & pure. Great power supply for explosive dynamics, too!

More info at http://www.tmhaudio.com/Metronome.htm

I've been a tube guy forever and using the Manger's with a quality solid state amplifier is nothing short of breathtaking.

Jim Ricketts/tmh audio
I have heard all the Manger speakes made by the company. The best result comes out with powerful fast amps.I got a fantastic sound using 103s with Gamut electronics.Both these products have their detractors,but brought together under the right conditions,the combination can take on some the best.I suggest all Manger users to try using Gamut electronics with Mangers.When using Gamut,please use their own balanced interconnect cable only.
Sphere.
I agree with Jim: I was going to review the Mangers for Ultra Audio, but they arrived damaged. Nonetheless, I set them up to see if they played. They were freaking DAZZLING....I could hear into the soundstage in a way that the Genesis 6.1s that I reviewed for Ultra Audio didn't even come close to, although the Genesis had deeper bass. My brother, who knows nothing about audiophiledom, said that this was the first speaker that sounded like there was actually a person playing music live.....and this was with a little Arcam A65+ integrated. I kid you not: it reminded me of when I was the Equipment Manger for Fi Magazine, and I went to Larry Kay's house and heard his Grand Slamms with a Rockport turntable and Jadis Electronics: you could actually "see" the instruments instead of looking at the "outlines" of the imaging. And I was only using a JVC XL Z-1010TN. I have lusted after a pair of them ever since I had to send them back....
GB,

You, your brother and I are defnitely on the same page. The realism is what jumps out when you hear any Manger loudspeaker and it's unmistakable.

The Manger louspeaker has caused this SET tubeguy to re-think amplification. I can no longer accept slow, colored, mushy, bandwidth limited, rolled-off extremes, excessively expensive SET amplifiers as nirvana. Indeed, those colorations and limitations are simply unacceptable if one is pursuing pure musical reality.

As an aside, Daniela Manger (and everyone at Metronome, too) not only designs state-of-the-art equipment that is superbly constructed with quality parts, but their honesty and business integrity is the tops. All of this is a most welcomed change.

Jim Ricketts/tmh audio
GM,

I forgot to ask in my last post, which Manger loudspeaker did you hear?

Thanks!

Jim Ricketts/tmh audio
Oh, Man, you HAD to ask which model it was?? Now, you'd think I'd remember, but I don't. I remember the price was around 9k for the pair, because UPS had to come and inspect the damaged box (man, they must have dropped it from 8 feet high!).
When you hear a speaker that doesn't have any "fog" whatsoever surrounding the instruments, THAT is what live music is like. Unencumbered by any artificial humidity, aka "noise," the sound simply moves through the air. I'm used to good sound, but this was simply exquisite. It's a shame they were damaged, because I couldn't be absolutely sure of the dynamic range/contrast or bass depth or any of that, but for a broken speaker that still played, well....props to the Manger!!!!!!
Who the h is importing these??? I remember that HP, back in issue 112, talked about the Audio Physics Medeas. They were in his Editor's Choice. He found them "dazzling." They used the Manger drivers, as he pointed out. I believe he said they sounded like ribbons without the colorations...
Oops, my bad. I HAD to look it up: issue 109, page 80...
"... Joachim Gerhardt's dazzling Medea, which features on each channel three of the jaw-dropping Manger drivers..." which has "...all the speed, quickness and detail of a great ribbon (which it is not), without some of a suspended-ribbon's flexing FM distortions..."
I think he liked-ed it.
GBM,

Your comment "doesn't have the fog" is a great description of the Manger speaker including the Zerobox 109. Watch for an upcoming rave review!!!

btw, tmh audio is the US importer. More info at http://www.tmhaudio.com

Jim Ricketts/tmh audio
In my opinion,which I have held for sometime,is that every electrostatic and ribbon loudspeaker manufacturer should own a Manger in their listening setup.This will allow them to resist over playing the transparency card,which mars many a fine planar loudspeaker.
The problem with the Manger lies in the fact that it sounds bad at most times with most setups.It is a task to get them to shine,but when an experienced chap does get it right,few loudspeakers can beat the 103 in every aspect of reproduction, and those few cost at least 2.5 times upwards the price of a 103.
Thanks Spere for your comments - the Manger's are quite extraordinary.

I have found them revealing of what you feed them but have been pleasantly surprised the "little" Zerobox 109 with its' 8" Scan Speak woofer can sound simply superb with a Sony receiver driving it.

Of course, we are using a Metronome front-end (typically the CD3-Sig, T2i-Sig or the Kalista/C2A combo) which is the best digital I have ever heard...and I'm an analog guy.
question about manger
can you used a few for professionel audio p.a
what is the dispersion from the high frequenties
greetings jack cross
Jack--your question is a bit incomprehensible. IF I get the gist: Mangers in a p.a. application, I'd say forget it. You don't have the the spl capacity in the first place.
I own 103 DIY for 10 years now.

Manger is depending (very) much on the electronics. That is somehow a disadvantage. Sometimes I would like to buy an amplifier which got superb reviews and has sensationell look only to find out that the rise time is to slow. Sh... Unfortunately for manger users the amplifier MUST be a fast one and a good one as many people already wrote to get the Best out of these beasts. But this sounds logical. If a speaker performs that well, of course you cannot connect just any amplifier and hope that this will work out wonders - to put it in other words: image fasten just any type of wheels to your ferrari and hope it will perform everytime perfectly well.

Tip: you can add Hologram profiles to the Manger to overcome the dispersion problems at high frequencies.

Another idea would be to activate the Manger. You can order an active module by for example Walter Fuchs former SAC. Activating Manger should be the ultimate solution as many report.

And by the way: even in passive mode the Manger perform exceptional. A Hifi freak which regularly comes to my place tells me every time that my system is the best DIY system he has ever heard. And he has heard quite many systems. He is old he should know it:-) And if you stay on the DIY side the sManger peaker should not come that expensive. Remeber even I own one:-)

Cheers Wolf
Wolf -- what's "hologram profile"
Hi Gregm,

the holoprofiles are a kind of plastic thing which have to be placed on the manger speaker itself. They costs around 400€ per pair.

Advertisment Manger: "Our latest development, the Manger Holoprofile, sets new standards in stereo reproduction. You can finally break free from the limitations of the stereo triangle with our patented sound deflector system."

Here is a link in german, but at least you get an idea and how they look like:
1:http://www.manger-msw.de
2: Select german
3: Click on "Produkte"
4 :Click on "Holoprofil"
Thanks, W.
Manger is fast driver and needs fast amplifier and wide bandwidth source.
I believe Mangers have been used in PA applications in Germany.
You should find out from your local dealer how Manger has gone about doing this.
Sphere.
Use four Manger drivers per side (for loud rock music) and your ears will close very early because it will sound as dynamic and real as "live" rock music. With other speakers I feel the sound more fuzzy and dynamic contrasts are muffled so the listening fatigue comes a little later.

If I listen to loud music at home, the listening fatigue caused by conventional drivers (Seas Excel 2-way) makes hum, buzz, fizz and other noises in my head.

The same loudness from Manger Zerobox 109 makes only fizz and this effect terminates earlier.

I like my ears so I use Manger.
Up the thread a ways, in a reply to Essentialaudio (Brian Walsh), D edwards wrote:

"I cannot write an experience for you but no SoundLab is ever going to win an award for clarity, not with the reverb off the back wall (100% distortion)...",

I'd like to address that comment.

Twenty something years ago I held essentially the same opinion, but then my ears-on experiences as an amateur speaker builder didn't bear it out. Seems the ear doesn't always hear the way the mind reasons it should. So I spent many an hour in the public library poring through old audio engineering journals trying to gain a useful, if rudimentary, understanding of how the ear/brain system works.

Now for the record, we could certainly write a definition of distortion that would necessarily classify a dipole's backwave energy as "100% distortion", but our definition would be arbitrary and inconsistent with the psychophyisics of human sound perception. [Distortion perception is an area still being intensely researched by some of the top minds in psychoacoustics.]

To the ear, the backwave of a dipole is not 100% distortion; rather, it is reverberant field energy. If reverberant field energy were undesirable, concert halls and recital halls would resemble anechoic chambers (which they don't). As long as the reflections aren't too strong and distinct (diffusion helps here), you can have rich ambience and excellent clarity at the same time, as routinely demonstrated by live unamplified performances in good venues. SoundLabs are exceptionally good at getting the reverberant field right, something that live voices and instruments routinely do but few loudspeakers emulate. A spectrally correct reverberant field is conducive not only to natural timbre, but also long-term fatigue-free listening. I can explain why this is so if anyone is interested.

Also, note that a line source speaker like the SoundLabs generates a much higher ratio of direct to reflected sound energy at the listening position than does a typical direct-radiating point source speaker, even factoring in the backwave. This can be readily demonstrated by comparing the actual SPL measurements recorded at different distances with the predicted anechoic SPL, the difference being reverberant field contribution.

Arguments over subjective impressions are usually fruitless, but I will go on record as saying that in my opinion SoundLab electrostats have exceptionally good clarity and inner detail. Those who feel that a dealer's opinion can't possibly be sincere, discount mine accordingly. Apparently D edwards arrived at his negative assessment by reasoning rather than by first-hand experience. We all make assessments by reasoning things out to the best of our ability - there's nothing wrong with that approach, but in this case I think that his assumption regarding the effect of the speaker's backwave energy is incorrect.

Duke
Duke,

This thread is about the Manger driver and Manger speakers. Your marginally factual, misleading post and assumption about how I came to my opinion is poor form. Maybe you should ask me to clarify my position so you understand what I'm talking about.

Look I don't want to pick on the Sound Labs to address your assumptions and very creative interpretations. but let me suggest that you are behind the curve and the world is not "ideal" which you heavily count on to make your point.

Maybe you should measure your Sound Labs and see what they really do like I have, then maybe we can talk about it. As you took great pains to tell us about what we hear and what we measure maybe you'll find that what you think you hear and what your really hearing is just as incongruent.
Duke;

I know how convenient it is to think I've never heard a Sound Lab M-1 or U-1 but you forget that these speakers are almost unchanged for 25 years or more, It hasn't been difficult to get to hear a Sound Lab when their have been dealers and clients near by.....try to find a manger dealer 10 years ago!

Like Essential Audio Duke, please share your Manger systems experience with us so maybe we can arrive at a mutual understanding of my Sound lab (or any dipole speaker) comments. Or maybe you simply find my comments unimaginable.

There is much better ways to getting a proper reverberent field than spilling a 100% out of phase fullrange signal into the room and bouncing it off "spectrally correct?" drywall...
D Edwards,

I think it's more than fair to enter a thread to address what I believe to be misinformation, and that's what I did.

If I have misinterpreted your statements I apologize, and invite you to clarify. I also invite you to let me know which of my statements you're characterizing as "marginally factual" and "misleading".

Fo now I'll hold off responding to your final paragraph, as there may be a better place for that discussion. I have measured my SoundLabs and I can talk about it, but once again there may be a better place to do so.

How about this: Let's see if we can narrow down exactly where we disagree, and then if you are interested, we can start a thread on the subject and present our respective views. This might well end up being of general interest to others.

Rather than my risking mis-interpreting your position, in the interest of continuing our discussion in a dedicated thread, would you clarify exactly what you see as detrimental about the backwave energy of the SoundLabs?

Duke
"Rather than my risking mis-interpreting your position, in the interest of continuing our discussion in a dedicated thread, would you clarify exactly what you see as detrimental about the backwave energy of the SoundLabs?"

Its the backwave energy of ANY fullrange dipole or bipole, its a delay channel. My Apogee's, magneplanars and Martin Logans all have the same issue, and as you indicate can be minimized to a degree but is that what I want? Some people do, but I'm way past that.

How can a speaker with a marginally controllable fullrange effects/reverb system win a clarity contest?

Psycho-acoustics? please, thats a pretty broad stoke.

Our disconnect is you cannot articulate any quality experiences with the Manger, then that is where our miscommunication is going to remain. One day when you hear the Manger....I recommend Overkill Audio product then you will have my perspective about clarity.

I don't want to talk negatively about Sound Labs and other Dipoles but they have issues which hurt them in areas like clarity, even though some fake clarity very well, its just that, a fake. You're a speaker expert I'm sure I don't have to explain how its done.

A multichannel surround system clearly will demonstrate that although pleasing this fixed dipole "reverb" clouds and homogenizes the image of a dipole speaker like the Sound Lab. You just want to overlook the detrimental aspects of slapping a fullrange signal off some drywall and assume psychoacoustic will explain this very un-ideal situation into a positive, I can't imagine anyone not thinking this is very very optimistic.

I think what you failed to take into consideration is these comments were in reference too the Manger driver, a vastly superior drive element to the technology used in the Sound Lab. And because it appears you have little or no idea what the Manger can do you take my comments as a big insult to the Sound Labs, well it wasn't, because the Sound Lab has to do very many things extremely well to simply lose out to the Manger on clarity.

So why should I debate someone who simply cannot put my comments into proper context?

The backwave lesson will cost you, you want academic information you gotta pay the academic fees.

----------I also invite you to let me know which of my statements you're characterizing as "marginally factual" and "misleading".----------------------------------------

"To the ear, the backwave of a dipole is not 100% distortion; rather, it is reverberant field energy. If reverberant field energy were undesirable, concert halls and recital halls would resemble anechoic chambers"

Complete false analogy and misunderstanding of how the backwave is working and the difference between reproducing sound through speakers and listening to live sound. You glorify two delay channels, why not get a surround system? Can you really be a two channel guy when you listen to 4 anyway? off the topic kinda but I'm curious.

"SoundLabs are exceptionally good at getting the reverberant field right, something that live voices and instruments routinely do but few loudspeakers emulate."

Can you answer how they get the reverberant field right, or is this just a quantification of your experience. How can something that makes everything sound 7 feet tall be getting the reverbent field right? Maybe you just like the extra reverb on your music....singing in the shower type thing?

"A spectrally correct reverberant field is conducive not only to natural timbre, but also long-term fatigue-free listening. I can explain why this is so if anyone is interested."

Correct timbres relating directly to the frequency response of your drywall....no need to explain. Theory is nice but reality is difficult and non-linear.

Note that a line source speaker like the SoundLabs generates a much higher ratio of direct to reflected sound energy at the listening position than does a typical direct-radiating point source speaker, even factoring in the backwave.

Over what listeing window or to be specific gate time? Over a very short window yes, but open the window wider and here comes the 2nd blip....what to do with all that maybe correlated maybe not correlated signal?

"D edwards arrived at his negative assessment by reasoning rather than by first-hand experience."

You're the one who never heard the Manger, you should be sorry for making a completely false statement to set the record straight about the Sound labs?

Isn't that ironic? LOL!
Dear D-edwards,
I was really kicked about reading the projest you did 7 years ago.I too am thinking about a Manger based project but using the opposite path,utmost simplicity.A 400 cycle 1st order x-over using two Scanspeak 18W/8546-00 for the lower duties.
Would be nice to hear your opinion.
Sphere.
Some of D edwards questions or statements, and Duke's responses:

D edwards: How can a speaker with a marginally controllable fullrange effects/reverb system win a clarity contest?

Duke: This is a good question, and gets right to the heart of the matter.

Clarity can be degraded by resonances in the driver, enclosure panels, or enclosure internal airspace; by resonances within the room; by reflections (in particular strong, distinct ones - the technical term is “specular”); by frequency response aberrations; by severe distortion of the initial waveform; and by diffraction. There are probably other mechanisms that don’t come to mind right now.

In this discussion we’re focusing on the backwave energy of the SoundLabs, but note that they don’t have any kind of box resonance; they don’t generate floor and ceiling bounce reflections; they have a very smooth frequency response; they are inherently time and phase correct; and they are directional enough that they don’t generate diffraction artifacts. They do have “drum-head” resonances within the individual cells, but the size of these cells is staggered to spread out these resonances so they don’t sum to an audible peak.

Now note that all loudspeakers generate off-axis sound (and therefore reverberant energy). If reflections can degrade clarity, then one could argue that all else being equal the speaker with the highest direct-to-reverberant sound ratio is likely to have the best clarity. Wouldn’t you agree?

A few years ago I measured the output of a point-source-approximating speaker (6.5 inch two-way) and a SoundLab M-1 at a distance of 1 meter, and again back at 8 meters, in a living room. I used pink noise, with NO time gating, so that the room’s contribution would be fully included.

Anechoic theory predicts that the output of the point source speaker would fall off by 18 dB going from 1 meter back to 8 meters (three doublings of distance). Anechoic theory predicts that the output of a line source speaker would fall off by 9 dB over that same distance. So if the in-room SPL falls off by less than anechoic theory would predict, that difference must come from the reverberant field contribution. Wouldn’t you agree?

The point source speaker’s SPL fell off by 11 dB over that distance, which is 7 dB less than anechoic theory would predict. So the reverberant field was contributing 7 dB back at 8 meters.

The SoundLab’s SPL fell off by 4 dB over the same distance, which is 5 dB less than anechoic theory would predict. This means the point source speaker’s reverberant field was contributing 2 dB more than the SoundLab’s was, even INCLUDING the backwave! That translates to about 60% more reverberant field energy from the point source speaker.

This proves that SoundLabs generate less reverberant energy in the room than a conventional speaker does. Now I’m an advocate of diffusing that backwave energy so that you don’t get a specular reflection, and once it’s diffused it doesn’t have the characteristics that would audibly degrade clarity. (Helmut Hass, “The effect of a single echo on the audibility of speech”, Journal of the Audio Engineering Society, 1950's [as I recall]).

D edwards: Psycho-acoustics? please, thats a pretty broad stoke.

Duke: A late-arriving, diffuse, slowly decaying reverberant field has been shown to be desirable from a psychoacoustic standpoint. (Pisha and Bilello, “A Live-end/Dead-end room, Part I”, Audio magazine, mid 80's.)

D edwards: Our disconnect is you cannot articulate any quality experiences with the Manger, then that is where our miscommunication is going to remain.

Duke: Whether or not I articulate any quality experiences with the Manger has nothing to do with this discussion. I’ve heard the Manger three times that I can remember. How in the world does that relate to a discussion of a completely different speaker? I’m not engaging in a “my speaker can beat up your speaker” debate.

D edwards: I don't want to talk negatively about Sound Labs and other Dipoles but they have issues which hurt them in areas like clarity, even though some fake clarity very well, its just that, a fake. You're a speaker expert I'm sure I don't have to explain how its done.

Duke: Sorry, but I’m not that much of a speaker expert - how do you fake clarity? Maybe you mean by tipping up the high frequencies? I’ve seen realtime unsmoothed wideband frequency response measurements of the SoundLabs, and they have a gently downward-sloping frequency repsonse curve - no artificial treble boost. The measurement was not time-gated, and it was the smoothest unsmoothed curve I have ever seen by a considerable margin.

D edwards: A multichannel surround system clearly will demonstrate that although pleasing this fixed dipole "reverb" clouds and homogenizes the image of a dipole speaker like the Sound Lab. You just want to overlook the detrimental aspects of slapping a fullrange signal off some drywall and assume psychoacoustic will explain this very un-ideal situation into a positive, I can't imagine anyone not thinking this is very very optimistic.

Duke: I've addressed the drywall issue (use diffusion). In my opinion the theoretical ideal would be an anechoic room with all of the reverberant energy you would have heard in the original venue reproduced by dedicated surround channels. Maybe one day we’ll have the recordings and systems to go there. Also as mentioned earlier, I advocate diffusing the rear channel energy - especially if it’s going to arrive within less than 10 milliseconds of the direct sound (Richard C. Heyser, review of Quad ESL 63, Audio magazine, early 1980's).

D edwards: I think what you failed to take into consideration is these comments were in reference too the Manger driver, a vastly superior drive element to the technology used in the Sound Lab. And because it appears you have little or no idea what the Manger can do you take my comments as a big insult to the Sound Labs, well it wasn't, because the Sound Lab has to do very many things extremely well to simply lose out to the Manger on clarity.

Duke: I do not comment on your claims about the Manger’s performance. As I said, I’m not engaging in a “my speaker can beat up your speaker” debate.

D edwards (starting out by quoting Duke): "To the ear, the backwave of a dipole is not 100% distortion; rather, it is reverberant field energy. If reverberant field energy were undesirable, concert halls and recital halls would resemble anechoic chambers"

Complete false analogy and misunderstanding of how the backwave is working and the difference between reproducing sound through speakers and listening to live sound.

Duke: I’ve already responded in part, but if you’ve ever seen the microphone placement at a recording of a live performance in a large hall, you’d know that the microphones are positioned to pick up a much higher ratio of direct to reverberant sound than what people in the audience would hear. The recording is made with the expectation that some reverberant energy will be added by the playback room. And in the interest of recreating a natural sound field, that reverberant energy should come from all around, not just from the two loudspeakers (which would be the case in an anechoic environment). (Jens Blauert, “Psychophysics of Human Sound Localization”, a psychoacoustics text).

D edwards (starting out by quoting Duke): "SoundLabs are exceptionally good at getting the reverberant field right, something that live voices and instruments routinely do but few loudspeakers emulate."

Can you answer how they get the reverberant field right, or is this just a quantification of your experience. How can something that makes everything sound 7 feet tall be getting the reverbent field right? Maybe you just like the extra reverb on your music....singing in the shower type thing?

Duke: The ear derives directional cues (including image height) almost entirely from the first arrival sound, not the reverberant field. This is very basic. You might want to look up something called the "precedence effect".

Set up correctly, SoundLabs do not make everything sound like it's seven feet tall. If the panels are exactly vertical, the image height will be at ear height, whether you are sitting or standing. This is because the shortest path (first arrival sound) will be to that part of the panel that's at ear height.

A live instrument in a good hall gets the reverberant field correct, wouldn’t you agree? What then are the distinguishing characteristics of that reverberant field?

1. There is a considerable time delay between the first-arrival sound and the onset of reverberant energy.

2. The reverberant field is highly diffuse

3. The reverberant sound started out with the same spectral balance as the first-arrival sound, and the only modification to this spectral balance has been done by the room’s natural acoustic characteristics.

4. The reverberant field decays fairly slowly.

Now some of these characteristics are largely room-dependent, but number 3 is highly speaker-dependent and in a given room number 1 is controlled by the speaker’s directional characteristics (in the case of the SoundLabs, the time delay imposed by the distance off the back wall delays the arrival of the backwave energy that much longer than would have been the case if it had been included in the frontwave).

D edwards (starting out by quoting Duke): "A spectrally correct reverberant field is conducive not only to natural timbre, but also long-term fatigue-free listening. I can explain why this is so if anyone is interested."

Correct timbres relating directly to the frequency response of your drywall....no need to explain. Theory is nice but reality is difficult and non-linear.

Duke: Actually, I think there is a need to explain at least a little. The ear derives timbre from both the direct and reverberant sound. At normal distances in a semi-reverberant room, most of the energy that reaches your ears is reverberant energy.

The listening fatigue part would take me a long time to explain. I’ve done so in other threads, so will simply post a link:

http://www.audioasylum.com/forums/hug/messages/101458.html

D edwards (starting out by quoting Duke): “Note that a line source speaker like the SoundLabs generates a much higher ratio of direct to reflected sound energy at the listening position than does a typical direct-radiating point source speaker, even factoring in the backwave.”

Over what listeing window or to be specific gate time? Over a very short window yes, but open the window wider and here comes the 2nd blip....what to do with all that maybe correlated maybe not correlated signal?

Duke: See the measurements I posted above, which were not time-gated. They demonstrate that the relative reverberant field contribution is greater with conventional speakers.

I apologize for not posting exact dates and/or page numbers in the sources I've cited, but I'm going by memory and not writing a thesis paper here.

In an earlier post, D edwards wrote:

"Maybe you should measure your Sound Labs and see what they really do like I have, then maybe we can talk about it."

I've talked about some of the measurements I've made on SoundLabs. So now let's hear about the ones you made - tell me "what they really do".

Duke
One thing I missed in my (incredibly long-winded) reply to D edwards -

You mentioned that the backwave energy generated by the SoundLabs is "maybe correlated maybe not correlated".

Excellent observation! When you wrote that, I hadn't yet posted much about diffusing the backwave energy. I believe it should be decorrelated as much as possible and diffusion is a simple way to do that. The ideal would be a broadband diffusor like an RPG panel, but a fake ficus tree is a good poor man's first approximation.

Duke
Duke,

What exactly would be the benefit to me in explaining my research to you?

and thanks for the apology.

Too bad we never met, Warner imaging and ATC both almost flew me to see you so you would "get it", how's that for a 'round about, people willing to spend money for me to educate you :)

isn't that funny!
Doug,

I didn't realize Warner Imaging was still in business. I used to be a dealer for Emil. Those were some very, very nice amps.

I was a dealer for ATC, and probably would be today if I hadn't started putting my nickels into my own speaker projects.

I'm still not sure how either of those companies or their products relates to what I objected to - namely, your statement that the backwave of a dipole is "100% distortion". Presenting the opposing view (and then subsequently defending it) is all I was trying to do, and obviously my skill at presenting an opposing view without it coming across as an attack needs some polishing.

I don't know you, nor anything about your research. What can you tell me, or can you point me to a website?

Thanks,

Duke
For clarity sake I think its important to note that I don't disagree with what Duke is stating other than how he is applying these theories to the subject as all encompassing explanations which is the only area I disagree. The deviation from ideal is where my point is defined, In the vacuum of the theorethical conditions Duke is correct as we know psychacoustics today.

The comment about the scale of image for example, the comment about "not being setup right" means that no fullrange Dipole system I have ever heard has been setup correctly. Because A dipole's cancellation isolates the rear wave into a distinct channel and this channel is always going to behave ideally which Duke's argeument hinges on. And its affect although pleasing still represents signal distortion as do reflections from other areas as you will find in all speakers. The inherent decoding problem of only using two speakers is another factor in this discussion and it is too complex to explain in short points. I have no motivation to write the 5000 words minimum to explain my position, only to have it picked apart for the sake of saying one's opinion about the clarity of a speaker.
Doug,

Thanks for letting me know that we aren't nearly as far apart as I had thought. I have many questions (in the interest of learning rather than debating), but as you pointed out earlier this is a Manger thread.

To Fatparrot: Looks like I pretty much ended up hijacking your thread. My apologies; I'll bow out now.

Duke
I have listened to the Manger driver for approximately 2 hours/day for the last 7 years. I have also listened to a pair of ESL's extensively for the past year. To my mind the ESL's beat the Mangers in most areas. Of course the drawbacks to the ESL's are low SPL in lower frequencies and maintenance requirements and longetivity. However, for higher output the Mangers are excellent drivers if configured appropriately. But beware, this thread contains an disproportionate amount BS. I suggest you spend the money, buy the Manger and build yourself something. This will tell you a lot more than this useless thread can do.
Hi,

I have been a Manger Zerobox 103 from quite some time now, all I can say about this speaker is WOW!!! have been in this hobby from the past 3.5Years with 4 Speaker changes but this one is Special.

They have a tone that is unmatched resolves quick with every detail in the recording its a speaker that does very little to the music a pleasure to listen to eveytime.

I have it hooked up with a tube amp a very unique one in the way its made, its a Hybrid 4 845 in Parallel Single Ended mode 50-Watts Class A and 200 Watts Class AB. Cadence Canasya 845.

http://www.cadenceaudio.com/productfr.html

The most interesting manger I have yet seen is called the Accupulse.
http://users.skynet.be/accupulse/

The site is a must see for any manger fan.

Best Regards,

Satyam.