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

In house are the Manger S1 active speakers. My dealer laughed at my buy stating that they suck. I had bought the Audiovector R3 on his recommendation and indeed it is a very great speaker. The R3 was no match to the S1 speakers. The S1 speakers are far superior in sound quality compared to the R3.

 

Paired with two Rel S812 subs they are an incredible buy. Fast, Zero distortion and simply stunning. Running all Teo Audio IC’s that has that 300B tube magic.

 

 

As the US distributor of Manger, I would like to thank Derek for his wonderful explanation of the advantages of the Manger driver. At the upcoming CES, we are introducing a special version of the Zerobox 109 - the AG Silver Edition driven by an ultra fast amplifier (Delta Sigma) from Italy that is flat to 3Mhz.
I hope the following new perspective helps clarify a couple of points on the THD driver distortion front.
If we look at the whole audio chain from source to drivers and look at the audio signal as one continous signal does it really matter where the distortion occurs?
If the true and total accumulative THD of the signal was measured from source through to the output of the loudspeaker drivers, could we measure or hear if the distortion was all in the source, all in the amps or all in the speakers?
If the total system THD figure was say 3% could we tell if each component in the chain added 1% or was the source "perfect" and the amp a super clean 0.0007% so it had to be the fault of the speakers?
Why are some of the worst measuring digital sources (Zanden and most NOS DAC players) reviewed and acclaimed by buyers as the most natural and life-like sounding?
Ditto SET amplifiers and valve pre amps, many exhibit over 1% distortion in real load measurements yet they are again bought and treasured as the most natural sounding. How can they be even close to in performance terms, never mind the prefered choice over many of the "so low its basically zero" distortion amps?
My last question is do we actualy believe that if we replay the most perfect high resolution recording of a powerfull piece of music on a $Million system made up of a THD 0.5 % source, a THD 0.5% amplifiers and a THD 0.5% pair of speakers that our ears will agree and tell us "yes that is 98.5% indistinguishable and a 98.5% perfect reproduction of the live event?
No way on gods green earth!
With current technology, we are obviously a million miles away from being able to reproduce the power and complexity of real music.
My point is this; Our current obsessive "tunnel vision" with THD is focused on the wrong distortion. THD is Total HARMONIC Distortion we need to measure
Total Signal Integrity Distortion (TSID).
This is what I have been focussing on for the last 6 years.
I will make a seperate posting for more on the importance of Time coherence in the audio signal.

In summary current THD only measures amplitude and frequency errors ie THD is two dimensional!
Despite the smoke and mirrors marketing of conventional speaker manufacturers, the very pretty 3 D waterfall plots from speaker measurement software are still only 3D representations of a two dimensional event.
I hope this is of interest and helps further the debate.

"Time Will Tell"

All the best

Derek Wilson
Overkill Audio
Hello Sphere,

Yes I agree, we need to do things differently in our marketing and distribution.
Hopefully we will find the right people to work with in the USA and then it will be up to the customers to decide!

"Time Will Tell"
All the best

Derek.
Dear Derek,
I would say good for him, as he is doing something in his products that seems to have many in the audio world admiring them. I will put it like this, let Overkill do what it is doing best,i.e making a radical product at an approachable price point if possible. Clearly Overkill cannot be sold via the traditional High End supply chain. It can only succeed if you manage to find extremely dedicated resellers and clients who believe in the technical approach, which you will find.Therefore none of the traditional brands are your competition and hence do not matter.
Sphere.
Hi Sphere,

Yes it would be nice to have the income stream of Wilson Audio!
I wonder if Dave ever imagined in the 80's when he was selling cheap cones and domes in an MDF box (watt, no puppy!) for $2,000 a pair that 20 years later he'd get away with selling them for $200,000 in a phenolic resin box! Wow that marketing, er sorry, inflation thing must really be kick'n in!!!

All the best

Derek.
All I can say is, Manger, either love them or loathe them. I am in the previous camp.As I said earlier Derek, you have taken a brave path, hope you reach your goal financially, because in the end it is all about the money.
Sphere.
Eardrums, speakers, rights & wrongs.EDITED VERSION!

"Unique" has almost become a tired old cliché in the world of high end AV. Every man and his passive crossover are claiming "unique this" and "unique that". The sad truth is that 99.9999 (yes six nines!) of all the loudspeakers in the world are all using exactly the same, fatally flawed, 100 year old technology that does not work! Pistonic motion (cones, domes, ribbons and panels, yes including Quads!) and passive crossovers (inductors, capacitors and resistors) were first used in audio in the early 1900's! They didn’t work then and they still don’t work today, here are the two reasons why.
Timing, Timing and Timing & Speed, Speed and Speed . Please be patient, read on and allow me to explain this radical but true statement. OK, hold on to your preconceptions cause this is really going to put the hungry cat among the fat pigeons!
Timing first;
The human (and all the other land based mammals) ear does not care what a sound is, what a sound sounds like or if a sound is pleasant or unpleasant. All that matters is where a sound is coming from in three dimensional space. All mammals ear brain mechanisms were developed to locate prey or flee from predators. In mammals the primary trigger for the fight or flight response is aural. When our primate ancestors detected a noise they instantly bolted in the opposite direction, away from the source of the noise. They may have been 10 meters into their flight response before they correctly identified the sound and realised it was as a false alarm… like a falling coconut. Or they may have identified a snapping twig as a predator was about to strike, then they looked back and thought that was close!
Natural selection ensured the survival of the creatures with the most accurate spacial location hearing mechanism not the most accurate tonal identification mechanism. So how does this well documented and accepted science & biology affect you and me in today's audio world?
To answer that we must first take a brief look at the mechanics of our ears and how they work, how they don't work and how fast they work.
Fact, our ears do not use pistonic motion!
Our ears use a rippling (or bending wave) principle to decode sounds. The outer ear channels sound waves (a series of compression and rarefactions in the air) down the ear canal onto the centre of the ear drum (imagine dropping a small pebble into the centre of a calm pool of water) which then ripples in response to this sound energy hitting its centre. Various tissues & tiny hairs and nerves located all around the edges of the ear drum (imagine how a spider uses its legs to detect the movement of struggling prey in its web) convert this movement, Kinetic energy, into electrical energy, and these impulses are then sent to the brain for decoding.
Now speed.
The ear drums response time is critical. How quickly the ear drum starts and stops the rippling motion determines the accuracy and effectiveness of our ears. Mother nature addressed this mechanical limitation by evolving the fastest possible energy conversion system, the rippling or bending wave ear drum motion. Pistonic motion is far too slow. The reason the ear drum does not work like a cone loudspeaker driver (a mass on the end of a spring) is because it would be in constant oscillation as it wobbles in and out never having enough time to settle back to its neutral or starting point. This would send a constant stream of "ghost echoes" to our brains which would be impossible to decode quickly and accurately.
Our ears are incredibly sensitive and specialised devices which are designed to detect where sounds are located (spacial information) in a fraction of the time it takes to identify what a sound is (tonal information).
The point to note here is that our hearing mechanism is ultra sensitive to time domain distortions. So the fundamental prerequisite in order for any loudspeaker to reproduce life like accurate sound is that its response time (speed) has to match or exceed that of the human ear.
Someone with average hearing can detect time domain errors down to an incredible 25uS (25, one millionth's of a second)or even less if your hearing is very good. The very best ribbon drivers covering 2KHz & above settle in an average of 100uS, the best dome tweeters have a settling time of between 140uS and 180uS, ultra fast midrange units need over 450uS to settle in the 500Hz to 2KHz band and a typical high end 12" bass driver can continue to oscillate and resonate for nearly a second after the initial musical note or impulse stops.
There is a driver which covers the entire 300Hz to 30 KHz band with a blindingly fast rise time of 13uS and does so without any of the ghost echoes and distortions caused by sluggish pistonic drivers slow settling times. It covers 90% of the audible frequency range with both rise and settling times that average over twenty five times faster than the very best pistonic drivers. Even more startling is the fact that this driver is so fast, the 13uS rise time is undetectable by the human ear, even a very good one! How is this possible I hear the sceptical voice cry?!
By refined the worlds only true rippling or bending wave loudspeaker system incorporating linear phase (time and phase coherent) digital crossovers and a genuinely unique cabinet material.
All full range loudspeaker systems are a combination of three equally important components; the driver, the cabinet and the crossover. In a world obsessed with measurements and statistics its easy to forget that it is more important how music sounds than how it measures.
A loudspeaker cabinet is not a passive box. Regardless of its material & construction techniques, a loudspeaker cabinet must be viewed as an active component which is equally important to the overall sound as the driver and crossover. The cabinet is an active energy conversion system, its job is to contain and convert energy, it must deal with the sonic back wave produced by the drivers it houses. Remember that the back wave disappearing into the cabinet is just as loud as the sound flowing into your room!
Creative engineering solutions can convert the kinetic (sound waves) energy of the back wave into heat energy by utilising proprietary viscoelastic materials and techniques.
MDF, plywood, hard wood, phenolic resin or plastic simply can not approach the energy conversion characteristics of this new unique 16 layer Self Damping Compound (SDC).
In acoustics the most important law of physics is, "for every action there is an equal and opposite reaction", so for all the musical sound you hear filling your listening room there is exactly the same amount of sound energy bouncing around inside the speaker cabinet! How can you convert this sound into heat before it bounces back out through the driver diaphragm out of phase!?
The only answer is…. ?
Hello Unsound,

You are right of course & I apologise for being lazy & just cutting and pasting a chunk off my website and posting it here.
If everyone did this it would be a giant advertising hording and not a forum!
I am in the middle of editing out all refrences to my website & products and I am removing all sales pitch material. I hope this "white paper" approach will stimulate some good old debate!
Overkillaudio, I was one of those that objected to your previous thread, and while I currently use cones and domes, that had nothing to do with my objection. This forums integrity could be compromised if blatant advertising such as yours was permited. If you can find your way to market your products appropriately, I wish you the best of luck.
Thanks Sphere!
It's very encouraging to get a positive comment rather than the usual " if its not what I have its no good" response that I usually get when I post the ocasional article on Audiogon.
I am going to have another go at posting my "Eardrums & loudspeakers" article tomorrow ( they removed the old one when the cone and dome guys complained, they thought I might make a sale!) after I edit out all the Overkill Audio name and product names and sales pitch stuff. I have posted it on another forum and its great fun to watch the feathers fly!

All the best and thanks again for your kind words.

Cheers

Derek.
Dear Derek,
I must congratulate you on the progress you have made with the product line over the past 2-3 years. There was a point, when I really feared that the unforgiving commercial audio mafia would not allow a shinning light like Overkill Audio to survive, as it has happened to many great products in the past. Once again my best wishes are with you for the success of your brave venture.
Sphere.
Hi Shadorne,

Good question! There is actally a Manger phase plug, they call it a "hollow profile" and you can read about it on the Manger site. I have tried it and I dont like it. It's a big flat piece of clear plastic that covers half(!) of the driver. Basically the Manger produces too much signal if that makes any sense. The way the bending wave generates sound means that it produces two of everything and in theory covering half the driver improves imaging.
But its ugly and my Prey units dispersion pattern is almost perfect.
The bottom line is with my Prey head units you have a superb but narrow "perfect" sweet spot and everywhere else in the room gets a very natural but not pin sharp , musical sound.
I hope this helps!

Cheers

Derek.
Derek,

I think they nuked the other recent thread. I expect you intended to post the information on this thread instead.
In any case I read about the Manger driver and am curious how it controls dispersion. To me it behaves like a ring radiator and therefore it will have a very narrow and extremely bumpy off axis dispersion pattern - at least without a phase plug...why no phase plug?
Hi all,

Please allow me to introduce myself. My name is Derek Wilson and it is with great trepidation that I enter your audio lions den!
For I bring some bad news for all fans of cone, dome, ribbon, panel (all things pistonic) and of course the evil passive crossover!

I do hope you will remain open minded after taking the time to read all the science, biology and technology that is detailed on the new Overkill Audio website.
I don't think I can print the link here but in the end there can be only one!
Our Finale, Encore, Predator, Prey, Angel and Dark Angel speaker systems along with The Conductor & The End Game should be easy to find and hopefully very difficult to ignore!.
As pretenders to the throne we must earn or shot at the title and we hope that the last 6 years of R&D and the fruits of our labour (again please see Overkillaudio website) will prove that we are indeed serious contenders. I do hope we will be allowed to organise some demonstrations and properly controlled independent audio shootouts in America. The first of the European shootouts will begin in the early spring 2008. For the lucky few music lovers who can afford $30 to $60K there is now a solution to all the audio reproduction problems.
I believe a year from now the Emperor is going to look very naked!

I thank you all for your time in advance of your replies (Gulp!) and as the great Winston Churchill once said " Whilst I totally disagree with you 100% I will defend until my dying breath your right to disagree with me"
Long live democracy!

Yours Sincerely

Derek Wilson
Overkill Audio
The Audio Physic Medea speakers were at the heart of the single most awesome moment I've ever had in the high-end hobby.
I was privileged to hear them at Immedia in Berkeley some seven years ago. They were utterly compelling, "hors classe" in a way that I've never heard a cone-driver speaker (or horn, or planar, etc.) even approximate.
The system backing the speakers, ohhh let me think - monoblock amps by SiriuS, the company that is now GamuT. The preamp was a Connoisseur Definitions v2, and LPs were spun on an Immedia "Revolution" turntable, of which too few were made. I was on the list for one such before I experienced a cash-flow discontinuity....
Wonderful speakers. Beyond my means then and now. But they are ranked among the very few products, audio or otherwise, that I wish I'd made the extra effort to know better.
Much like that girl who I really should have kissed when I was seventeen.

More wine, waiter!

cheers apo
I have been playing the manger drivers in a pair of Medea's, they need time to break in, took over a ytwo years, and theyy also need fast amps, as well as powerful one's, they are reasonably efficient, but seem to really thrive on power.
What a gorgeous thread to join for I´ve been playing my Manger 103 Zerobox for many years now driven by tube amps.
My ears feel content so far, let´s wait and see what the instruments at the svoboda labs will find out.
I hope you test on open baffle and measure below or at 30ms.
Of course, without interpolating passive components. Since you're using a generator, limit the bandwidth if necessary.
OK, This is an update on my MANGER adventures.

I've put my money where my mouth is. It will take a number of weeks for me to actually get my hands on the pair I found, but the ball is rolling. I'll post specifics of the construction of test boxes, and choice of vintage piston drivers that may be a good demonstration of "bad cones". Then will follow details on the testing protocol for waveform fidelity. I plan to use an arbitrary waveform generator making music-like percussive impulses. Departures from ideal decay profiles as provided by the generator will be considered distortion that is added by the driver based on available damping factor, modified with series impedance added inline with the drivers. I may try to use several "full range" drivers to avoid loading effects of passive filter networks. Later, I will use this same setup to test for gamma (Bl/Mms(d))requirements in subwoofer drivers.

Stay tuned!
These distortions, unlike simple harmonics, are non-mathematically correlated, and occur in time AFTER the musical signal
Quite so. However, and apparently, these can be modelled -- but only with reference to electromechanical properties in each specific application. Unfortunately, I can't find a ref you may be interested in.

BTW, a simple experiment with very hard cone material coupled to powerful electromagnetic support, may reveal an "overdamping" effect (i.e. relative spl drops faster than projected -- further i.e., what we call "decay" is truncated, becoming "sub-audible" if I may coin the ugly word).

A very interesting viewpoint, Martin.
Finally;

MartinsV;

Where do people like you hang out?! because it is refreshing to see such insight and understanding, that I must admit that I share, well actually harbor your thoughts.

Its always risky to be so certain, but for all the negativity it will bring you; I couldn't agree more with your comments.
Not having heard the MANGERS yet, I only wanted to interject an observation I've made relating to pistonic diaphragms in general. The conventional dynamic loudspeaker has a diaphragm that is supposed to be perfectly rigid. As this is not actually possible with known materials, some distortions are inevitable. They take the form of bending waves and nodes like the choppy waves on the surface of a swimming pool after a person does a cannon ball into it.

I believe it can be demonstrated with laser interferometry experiments that a SLOW amplifier, one that has POOR DAMPING and TRUNCATED high frequency response, will excite these modes less in a poorly designed piston-type radiator. A voice coil attached to a narrow band of material on any "cone" or other common geometry not only has to accelerate the diaphragm, but also must yank it to a halt when the sound stimulus is supposed to be decaying/ending. With a power amplifier that has a high degree of control over the motor system, the equivalent is like a MAC truck hauling a trailer hitting a concrete bridge abutment. The area of the cab will stop in a hurry, but the rest of the vehicle will do a lot of moving before it’s over. A Fostex white paper discusses rate of propagation in materials being related to internal damping possibilities in a diaphragm, and its an interesting intersection that sapphire and diamond diaphragms are at the same time stiff and high-velocity with respect to internal sound propagation. If a given amount of damping is provided by added materials like the surround, voice coil interface, and the air load, the TIME period for the decay of undesired energy from the diaphragm is shortened, thus adding to “clarity”. This does not equate with total energy, but that may not have as much bearing on psycho-acoustic perception. Such diaphragms are likely resistant to the charms of weak amplifier coupling, as they don’t “benefit” from it.

I have a great deal of respect for Mr. Pass, and watched with some appreciation his arc of experience with this issue. I am bemused by the appearance of his missing this "link" as to why a "poor" amplifier might actually sound better. Driving speakers with diaphragm designs that "freak out" when presented with an iron grip on their voice coils by a high damping factor, high rise-time, wide band solid state amplifier using high local and global negative feedback to get there may be part of the explanation. I think the "distortions" are not the vanishingly low harmonic fuzz you get from imperfect group delay in feedback servo loops, but instead the complaints of diaphragms abused by their own voice coils. A tube amp may have an output impedance EQUAL to the voice coil impedance, for a damping factor of ONE. Try this experiment some time; lightly tap on the woofer cone of a speaker with no wires connected. Then do it with a 4-8 ohm resistor across the input. Then, short the input together on the speaker terminals, and tap again. Each report from your test bell will sound different, and your finger tapping sound is EXACTLY like the decay the speaker adds right after being stimulated by musical impulses. The smooth relaxed sound so many tube and SET aficionados care for may be the avoidance of stimulating break-up modes in conventional dynamic speakers. These distortions, unlike simple harmonics, are non-mathematically correlated, and occur in time AFTER the musical signal, rather than with it. Reducing them may indeed be a technical justification for seemingly reduced performance systems sounding better, in some combinations. Conversely, solving the dynamic speaker design problem by reducing these modes in a diaphragm deliberately may allow us to move away from pretty glowing tubes, and their other limitations.

All this leads up to the Manger. Instead of pretending it is a rigid piston like dynamic drivers to, it is a thin flappy membrane carefully tuned to produce MAXIMUM POSSIBLE NODES of bending from the voice coil motion. One can think of it as the worst pistonic speaker design ever, with near-zero rigidity. As such, it need not suffer from bending modes as distortion; it is the OPERATING PRINCIPLE instead, on purpose! Like the pretty ripples in a circular pool of water when a pebble is dropped exactly in the center, it is like a cross section of pressure/rarefaction in a spherical acoustical volume around a point source radiator. Up to a certain frequency defined by the voice coil diameter and material tension, it should be hemispherically radiating irrespective of its membrane diameter. The point is, the OPPOSITE effects of damping and bandwidth from an amplifier apply in the case of the Manger. A poor damping factor will make the amp unable to fully modulate the center of the "pool" of the manger, and thus not introduce the correct counter action to the high amplitude of modulation of the diaphragm, on the DECAY of musical signals. Think of an SUV with 4-wheel drive on ice; much easier to get going than to stop. The primary damping of the Manger is the air load it plays into, besides the voice coil and periphery materials. If you have a lackadaisical amp that used to go easy on floppy cone speakers, it will have no chance to get anything meaningful out of the Manger.

I applaud Mr. Pass for doing the practical footwork that bolsters my theory. I plan to do a physical demonstrator setup with a pair of Mangers and a variable damping factor apparatus, along with a representative pistonic system alongside. By introducing several series impedances in sequence, it should be possible to DEGRADE the apparent quality of sound from a Manger, and in some ways IMPROVE it from the pistonic.
Sbfx -- the diy you present reminds me of the those Audio Physic Medea I had many years ago.
The diyer probably achieved better implementation I assume...
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.
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.
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
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,

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
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!
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
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
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.
"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!
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
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...
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.
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
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.
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.
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"
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
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.
question about manger
can you used a few for professionel audio p.a
what is the dispersion from the high frequenties
greetings jack cross
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.