History on ohm A's and F's.

I panned through the threads and read how the old ohm a's were remarkable.
Would like to hear more about this and other ohm speakers.
I've owned Fs, two pair of Walsh 5s and a pair of Walsh Sats (similar to 100s). They float instruments very well, and are coherent, but the Fs are very recessed on top, and bass heavy except in very large rooms. The 5 is much better, but still a bit recessed in the upper mids, and the top is not as detailed as the best. However, they do present large scale works more realistically than most high end speakers and are highly musical, if given enough room and power. The S3s supposedly improve on the weaknesses of earlier versions. The sound of the Walshes is polarizing for audiophiles, but I think music lovers find them to be very endearing indeed.
I have 2 pairs of Ohm F.

All 4 speakers need repair as the foam disintegrates over time.

With proper power, let's say Chernobyl, they are among the finest loudspeakers I've ever heard.

Ohm A was basically a prototype. It was a 16" Walsh driver as opposed to the 12" Ohm F.

I believe very few pair were actually made available to the public.
Agree Ohm Fs were/are really nice. I think all of the newer stuff, including the 'upgrades' are lifeless and plastic sounding.

I think there is a guy that is building a new version of the model F; seems like he has advertised or sold a pair here on Agon.
Bill, Aren't the Ohm F's very difficult to recone? I think I read that there are only a couple of people who can perform this in the USA. Is this the case because I have seen a number of pairs here on the GOn. Bob
Extremely difficult to recone.

There is only one gentleman I would trust to do mine.

He's located on the east coast near Philadelphia and doesn't get involved anymore due to the time and complexity involved. I even offered him one pair to keep in exchange for one repaired pair (plus his parts cost and labor of course). So far no interest.

But I keep them hoping he'll change his mind.
Dale Harder recones original Ohm speakers and builds his own, improved versions of both A and F models. He can be reached at:

[email protected] or 440-888-2163 in Parma, Ohio
what do you think of the new 5-S3? I would like the MBL but too much money. Looking for something that is amazing and these have come up.. Thoughts?

I participated in some exchanges here on A'gon threads with Dale Harder a few months back, but not recently.

He seems most knowledgeable regarding what it takes to get a pure Walsh driver like those found in old A's and F's operating properly and has shared that info in the form of a guide both here on Agon and on Ebay. It is an extremely challenging task to accomplish in practice, as I understand it. I have also seen ads he has posted for both Ohm As and Fs here on Agon that he has completely refurbished for $5-6 grand (about the same price as a pair of new Ohm Walsh 5's) and they looked very nice. Would love to be able to hear them someday.

The closest things to Ohm As and F's today design wise are probably the larger and extremely expensive German Physics designs and Ohms own Walsh line based on the CLS driver.

I have heard most all Ohm box speaker designs from that era but never As or Fs so I cannot comment on their sound other than saying that many who did hear them remain dedicated.

Newer Walsh CLS speaks are definitely easier to drive (though the larger models still require very good amplification to do their best), are easier to locate relative to walls and are less problematic and more reliable overall.

The newer Ohm CLS speaks have better specifications on paper, but I have heard some Ohm F fans state that they do not think the newer Ohms have the same "magic" as the Fs.

One other thing of interest is that Ohm's website indicates that newer Walsh 5 speakers, like those like the F5s in my system, can be set to sound identical to original Ohm As using a certain combination of the 4 range level adjustments on the Walsh 5 cage.

My experience with most assertions on the Ohm site is that they are usually on target, for what it is worth.

I tried this with my system and found it a bit bass heavy in my larger 30X20 L shaped listening room. I've used similar settings in that room most recently but with the relative bass levels lowered somewhat.

In the current 12X12 main listening room I currently have the F-5s in (where I have access to best speaker cables, etc.), I lower the bass even further otherwise my fixtures will start to vibrate and I might well be driven out of the room at even moderate to higher level SPLs.

The weight, dynamics and overall impact the Walsh CLS speaks provide though when properly matched to room size is an exhilarating experience you will most likely never get with electostats or planar designs which may otherwise sound similar.

The Ohms and Maggies are the only speaks I can afford that I ever found endearing when set up properly with classical music but the Maggies alone cannot touch the Ohms in regards to overall power and impact.
The 5-S3 is a nice speaker, a good value.

However, it is not an Ohm F but nothing else is either.

The F is among my favorites of all time which includes Apogee Duetta, Quad 57, and Magnepan 20. You can see I am partial to panels or speakers that replicate the imaging of panels.

One drawback to the F was the lack of SPL. I believe the sensitivity was around 82dB. Very few amplifiers back then could drive them to rock and roll volumes that we were accustomed to vis a vis the other contemporary speakers such as ESS, RTR, Infinity, JBL, etc.

I remember listening to my Phase Linear 700B in 1973 getting sucked dry during the opening heartbeat from Dark Side of the Moon. Even at reasonable SPL the Phase Linear was gasping for breath and out of gas.

Great memories of the speakers and the recreational medication.

Have you heard Walsh 5 series 3? What electronics have you heard with them?

I'd be curious for a comparison between 5 series 3 and properly functioning Fs if you've heard both.

Have you ever heard the MBL's? what do you think of them compared to the Ohm's?

No,unfortunately never heard MBL, so I can't compare the sound.

I can compare the two designs however to some degree.

They are similar in that both are inherently omnidirectional using a single yet supplemented wide range driver.

The Ohms however are physically damped/attenuated in the wall facing directions by default to enable easier placement near walls, so their measured sound dispersion pattern is not purely omni-directional.

Also the Ohm Walsh wide range driver reside on top of the cabinet like larger MBL and German Physik for that matter and is supplemented on the high end by a directional super tweeter and ported to extend the low end, whereas I think the large MBL wide range driver is supplemented on the low end by a sub woofer.

Larger German Physiks, which use their own derivation of the Walsh design, are also supplemented like the MBLs on the low end by a sub woofer, I believe.

All these designs will claim a high degree of phase coherency from top to bottom.

Ohm claims that their near full range design produces most of the most important frequency range that most people over 40 can truly hear via the wide range Walsh driver used. The theory is that we lose our ability to hear the highest frequencies recorded in music as we age.

Ohm As and Fs utilized a single Walsh driver for all frequencies but rolled off at ~17Khz, according to the specs on the Ohm site.

Ohms and German Physiks use different derivations of Lincoln Walsh's original driver design (look up "Lincoln Walsh" on wikipedia for more info here). I am less familiar with MBLs omni design but from what I have read on their site it is a more radically different breed of omni design.

One a'goner here whose opinions I respect recently referred to the Ohms as "Blue Collar MBLs", which is probably a fair description in that Ohm Walsh speakers range in cost from $1000 to $6000 depending on target room size and finish, whereas big MBLs cost over $25000 as I recall, so some might consider the Ohms to be "giant killers" and all that goes with that designation.

Ohm is located in Brooklyn NY, USA. MBL and German Physiks are imported from Germany.
I heard them at a customer's house with a pair of Pass XA60.5 amps.

I can't give you an honest comparison for 2 reasons. First, I haven't heard a pair of properly driven F's for almost 20 years and it wasn't in the same room as the 5-S3 which is critical. Second, and more importantly, our "sonic memory" is quite poor. Any comparsion based on what was heard 20 years ago is not worth talking about now IMO.


What did you think of the 5-S3's?
It's a nice speaker; good value for the money.
I had heard the Fs in the '70s, and was very impressed by the power, scale and coherence of the sound. Years later, in the early 90s, I bought a pair of mint Fs to compare to the Walsh 5s I had so I could compare them directly.
To me it was not close. The F sounded heavy and slow in the bottom registers by comparison, and recessed on the top. The Walsh 5 was much better balanced and open sounding.
The decision as to which was a keeper was very easy for me, even though at the time the Walsh 5 was worth 4 or 5 times as much as the Fs on the resale market.
I had a very beefy amp (over 600 wpc into 2 ohms), so I had more than enough drive for either speaker.
From that, and later descriptions of the S3, I would say that it is very safe to assume the S3 is much better yet.
Hello Gentlemen, Ladies,

May I interject on the conversation? If you have not seen our new site please vist it. Love to have some feedback.


Also, Regarding the Apogees and newer versions being made by Graz, prices start at $50K and go up to $120K. As for MBL's they start at $55K and go to over $200K on the extremes. (If my memory serves from our last conversations. I do keep in touch with Apogee, MBL and German Physiks)

Oh, BTW, the German Physiks unit is a truncated Walsh cone with a 2" VC and about a 6" nominal diameter, crossed over at 240 Hz to a 10" woofer. The Old F was a 3" vc and a nominal 12" diameter.

Referencing the slow sound and lack of highs on the F's you heard I can relate. If the wrong voice coil, spider and surround are used in a recone as well as not replacing the damping foams and putties, the unit will suffer terribly. No highs, no transient response, muffeled sound, etc. will result. This is what I have been fighting so diligently.

I truly wish you all could feel and hear the magic these speakers are capable of producing. Funny, most women that come to my home/showroom are emotionally impressed, but to my suprise it has been the men that are most affected. Several have actually had tears run down their face and hair stand up from the experience. To me there can be no greater testament of their musical prowess and of shear musical enjoyment.

As always, I humbley wish you all the greatest musical experiences.

Dale Harder
The Huff line of speakers use the same driver as the German Physiks line, at somewhat more reasonable costs. The German Physiks might have more elaborate cabinets. I have no idea if they warrant the extra costs. The German Physiks driver is an update of the origianl Walsh design. While it might be better in many regards, it does not go down as deep as the original Ohm Walsh driver and unlike the original Ohm Walsh design might be best supplemented with a sub-woofer. Still, the German Physiks and especially the less expensive Huff design look mighty appealing. I wish I had the opportunity to audtion them.
Interesting. This is the first I heard of Huff and their exotic driver speaks. Nice that they are US made apparently. Price wise, they appear to live somewhere between the Ohm world and German Physiks.

So where can one go to on the east coast to actually hear them?
By the way, I would not consider Ohm CLS drivers to be "exotic".

The technology is unique and affordable, perhaps, but if you were to look inside the cage, the actual driver is butt ugly THBOMK. Thank God it is hidden! Its like that episode of Star Trek where that ambassador guy was so ugly he lived in a box and if you opened the box without the protective glasses, you went insane (even Spock)!
Even Spock???Surely you jest......don't call me Surely.Those Ohm from the 70's,forget the model was magnificent,cheers,Bob
Mapman: The Ohms and Maggies are the only speaks I can afford that I ever found endearing when set up properly with classical music...

Which specific brands did they beat out in your experience?

My comment was meant to apply to speakers that I have actually owned and tested over the years in my own house, not necessarily to any that I have ever auditioned or heard. There may well be others out there, but nothing I can think of offhand that I would consider over the Ohms.

$2800 B&W floorstanders (P6) and $2500 Dynaudio Monitors (Contour 1.3 mkII) are two that I own or have owned and tried.

I lost all interest listening to classical with the B&Ws after the Maggies. Though they had good weight and slam overall, they were never convincing with classical. Pretty good with other more rhythmic forms of music though.

The Dynaudio monitors, though fantastic for their size, are not totally convincing with large scale works including classical either.

I also still have a pair of Triangle Titus 202 monitors mated with a sub which does a very respectable job with all classical music forms.

Also I would include original Ohm Walsh 2's from the 80's that I owned for years....respectable but not great with classical.

The newer Walsh CLS series 4 drivers beat out all of these in every type of music, but for classical in particular.

There is no sense of missing anything in a performance of a large scale classical piece with any of the Walsh series 3 drivers in a properly matched size room.
"Even Spock???"

Yes, even Spock!

Although as I recal he felt better by the end of the episode.

I think it (the episode) was ironically called "Is There in Truth No Beauty?".

With the Ohms, I would say there is truth and still some beauty as long as you don't open up the "cage".
I would say there is truth and still some beauty as long as you don't open up the "cage".

Indeed Mr. Spock displayed much more emotion in "The Cage" than in rest of the series.
>>Indeed Mr. Spock displayed much more emotion in "The Cage" than in rest of the series<<

Not true.

See "This Side of Paradise" and "All Our Yesterdays" for an emotion filled Vulcan.
I may have a bit of an interesting perspective on the Ohm's since I'm a new Ohm owner.

I had to sell my old Vandy 2C's due to space considerations and aesthetic considerations (low WAF) in our remodeled house. I had it narrowed down to either a pair of Totem Arro's or a pair of Ohm Micro Walsh Tall's, which Mapman got me interested in here on A'gon.

In the end, the Arro's had more online reviews and more raves on A'gon, and so I made a more "conventional" choice with the Arro's, instead of what seemed at the time like a "weird-ass" choice (the Ohm's). ;-)

I was disappointed with the Arro's, not because their tonality isn't fine (it is) but because I found the much-touted "holographic" presentation lacking. I mean, they image nicely enough, but the "magic" wasn't there in my listening room. Plus, I found the descriptions of the Ohm's so seductive that I couldn't shake the thought that I'd like them better.

I took the plunge and ordered a pair of Micro Walsh Tall's.

They're nearly identical in exterior dimensions to the Totem Arro (an inch wider and an inch shallower, but the same height).

To my ears, the Ohm MWT's smoke the Arro's on a number of fronts:

1) Bass is far fuller and more authoritative.
2) The Ohm's really move some air when they need to, as opposed to the Arro's.
3) I'm sure there are people who find the Ohm's spatial presentation gimmicky or weird, but I love it. Instruments reach out into the room. Voices have space and air around them. On the right material, the rear wall behind the speakers vanishes into a deep soundstage. And orchestral music is convincing to the point of being truly moving or thrilling.

Disclaimer: the Arro's aren't fully broken in, as I was reminded/chided in another thread here. So be it. But I don't see the Arro's, even after their recommended 100-140 hours of break-in time, replicating what I find most impressive about the Ohm's.
See "This Side of Paradise" and "All Our Yesterdays" for an emotion filled Vulcan.

Ah yes you are right. I kind of meant in general though. The T'pau episode (Amok Time) also seemed quite emotional for our logical hero too - he sure seemed happy to see Kirk was not dead!
Kirk's not dead?Have you seen those commercials?Same voice,definately not the same body.They must of not shown that episode where you live where he...........can't remember now.....new chipset isn't working properly.To be continued......
Pardon my intrusion, but as the North American distributor for German Physiks I hope I can add some information to the discussion:

by the way - to my knowledge, Huff has not had access to the German Physiks DDD driver for quite some time. Holger Mueller (owner of German Physiks) said that he had stopped supplying the driver to OEMs some time ago.

Also - with regard to the technology in the German Physiks DDD driver - it is not a "truncated" Walsh driver as one suggested, but rather a bending wave driver (the Walsh was a purely pistonic driver, which was at the core of its efficiency issues).

The DDD is actually made from microns-thin titanium foil or carbon fiber, and the voice coil is not fixed hard to the cone but rather acts as a striker might act on a bell, causing predictable distortions in the surface of the foil ... which in turn project the sound into the air.

It is true that the DDD does not perform into low frequencies the same way the original Ohm driver did. Then again, it also doesn't require megawatt amplifiers to come alive, not will it melt down the moment it starts getting enjoyable.
"(the Walsh was a purely pistonic driver, which was at the core of its efficency issues)."
I think saying the Walsh speaks including As and Fs are pistonic is an accurate statement.

Regarding efficiency, though I would not doubt the DDD driver is more efficient than the original Walsh A or F drivers from 30 years ago, I think comparing a full range driver like those on the Ohm A and F to a limited range driver that does not cover the low end like the DDD is an apples and oranges comparison.
I do believe that unlike the current Ohms, the original Ohm Walsh's were bending wave drivers, and the German Physiks DDD is just an update of the original Walsh concept. The "inefficiency" of the original Walsh drivers might be due to other factors.
I think the Ohms were both bending wave and pistonic using a voice coil and foam surround.

Sounds like the drive mechanism for the DDD is different as described by Csommovigo as like "striking a bell", but honestly the exact difference is not clear to me.
The difference in basic operating principle between the DDD driver and the Walsh driver on original Ohm F and As is not apparent to me. The drivers are different sizes and cover different frequency ranges for sure, but both seem to operate similarly in principle in a manner one might chose to describe as pistonic or not...not sure what difference it makes because it appears to be the same. Whether pistonic or not, the bending wave principle for producing the sound appears to be the same.
I would also add the the Walsh portion of the newer Ohm CLS drivers also operate on the same bending wave principle.

That doesn't mean that old Ohm Walsh, newer CLS and GP DDD drivers necessarily sound the same. I am certain that they do not just like three different conventional cone driver designs that operate on the same basic principle sound the same.
Mapman, I could be wrong but, I believe you are mistaken on every count.
On all counts?

Ohm A and F: To my knowledge: (I'll have to ask Holger M. of GP, as he has direct knowledge of this) -

Ohm A/F drivers had their VC's hard-fixed to the cone, essentially able to erupt bendingwaves at high frequencies but, as the frequencies became larger, were responsible for moving the entire inertia of the cone.

The DDD does not have the VC hard fixed to the base of the cone, but rather - as I mentioned earlier - acts as a striker through a particular elastomeric glue to erupt bending waves in the surface of the titanium foil. It does have a pistonic mode, but that mode is not reached in any of the speakers except the Unicorn (as I recall) because it is able to remain a bendingwave driver throughout it's general operating range.

The original Walsh concept was just that - a concept. It took Gersten's unique voice-coil to make the concept a practical (used loosely) reality. Walsh died before the application was fully commercialized. Once the concept had been commercialized, the release was rife with failures. Theory and practice parted ways, as the business seemed to be engaged in as many repairs as they were engaged in new sales. At some point, I suspect, the repairs must have overtaken sales and it was time for a change.

Ohm's John Strohbeen created a hybrid concept, marrying a tweeter to an inverted dynamic mid-bass driver, and that design has been the "Ohm" design for a long time.

German Physiks' DDD driver was the invention of Peter Dicks, who - for the first time - applied the mathematics required to successfully model this style of bending wave driver. In so doing, he essentially invented the concept as a practical matter - converging theory and practice. Several more years in development at German Physiks had the DDD ready for prime time. Since 1992 the driver has been successfully commercialized.

Curiously - to say that the DDD is a variation of a Walsh driver (as described in LW's patent), in a fashion, to say that the Blackhawk helicopter is a variation of a drawing of a flying machine by DaVinci. While the DaVinci is certainly elegant and inspired, the GP actually works, and works with predictable precision and reliability.
The operating principle of the DDD driver, as used in the German Physiks HRS 120 (10-inch acoustic suspension woofer below 240Hz):

"The lower frequency end of its operating range can be described with Thiele/Small resonant parameters, while in the next frequency band up to the coincidence frequency 'it works like a pistonic driver'. Next, there’s an overlapping band where pistonic movement is 'progressively replaced by bending waves until all the radiation is generated purely by bending movement in the cone'."

Hi-Fi World review here.

Sounds like a reasonable accounting of the similarities and differences to me. Thanks.

IS it accurate to say that the different designs all operate on similar principles despite the fact that the implementation of each is significantly different, for better or for worse?
One other question I had was is it accurate to say that the lower frequencies with all of these designs are produced "pistonically" while the upper frequencies are produced by bending waves?

If so, then the Ohms must rely less on wave bending because the upper frequencies (>~14000 khz, I think) are produced by the separate tweeter whereas for most of the GP speakers, the low end (pistonic range) appears to be handled separately .

Still, other than the on e GP model I think, the Ohm Fs and As are the only speaks that use a single driver for the full range.

An advantage of wide or full range is the elimination for the need of a separate crossover device and a more "coherent" sound overall.
To my mind, it's "hardly a reasonable accounting of the similarities". In one case, we have an actual working model of a concept just a few decades old, as opposed to some drawings done centuries ago without any known working models. The Walsh "concept" may not have been as polished as the DDD due to the fact that Walsh died before he had the benefit of computer modeling to do the intricate math. Never the less, let us not forget that the working Walsh design had an even even greater frequency range. As Walsh had little to do with Ohms production standards, let us not blame him for alleged failure rates. Let us give the credit due to Walsh, without whom "Dick" might never had the premise upon which to refine and develop the the concept into the DDD. I'm just an outsider here, and while sincerely appreciate the input of those directly involved with these most interesting speakers, I'm a bit put off by what appears to be a slanted, unconfirmed and disrespectful assessment of the genius(?) of Walsh, and this applies to others who haven't posted here as well.
"Curiously - to say that the DDD is a variation of a Walsh driver (as described in LW's patent), in a fashion, to say that the Blackhawk helicopter is a variation of a drawing of a flying machine by DaVinci. While the DaVinci is certainly elegant and inspired, the GP actually works, and works with predictable precision and reliability."

This part is a bit biased I suppose.

Has GP's DDD driver solved the robustness issues of the original FULL range Walsh drivers on the A and F?

It doesn't seem so to me since it is not full range and does not deliver the low end. Unless I'm missing something, the DDD solution appears to be to avoid the problem, ie separate the low end off to another driver to avoid the stress and wear issues associated with delivering the low end "pistonically" along with the upper range that is delivered via wave bending all with the same driver, as I believe was done with Ohm As and Fs.

For newer Ohm Walsh speakers, they've elected to deliver the low end via the wide range (still not full range) Walsh-style driver. The rational Ohm provides is that most of what most people can actually hear (up to 14000khz or so) is delivered via the single driver and that preserves a lot of the benefits of the original Walsh driver design while avoiding the inherent fragile nature apparently of the full range Walsh driver design.

I don't mean to take credit away from Lincoln Walsh ... he refined the bending-wave concept into an omni design. He also managed to create a very wide-bandwidth concept. It remained a concept, commercialized by someone else (Gersten) who invented the voice coil without which it would nto have been possible. By all rights the driver should be referred to as the Walsh/Gersten driver because of that fact.

Next: The Peter Dicks driver parts ways with the Ohm driver in several ways. First of all, it was modeled more accurately. While Walsh was a genius (and so was DaVinci), he was unable to accurately model the concept in a way that would make it reliable. Dicks was able to do that. It is hardly "slanted" to say that - them's the facts.

I'm curious as to why you would take it so personally that someone might challenge the "genius" of Walsh? And it's not even a challenge, per se, but rather an assessment of the facts as regards the differences between the Walsh/Gersten driver and the DDD? Why so touchy?

The Walsh/Gersten driver resulted in failure. There are very few remaining working models in the field that have not been refurbished/repaired at least once in their lifetimes, and the design was abandoned by the company because it seems to have been a guaranteed liability. Their terrible inefficiency required tremendous power just to wake the driver up, and a little bit more power melted the voice coils.

Still - it remains one of the most interesting and well-regarded drivers in the history of the industry, and credit should be given where it is due to Lincoln Walsh for having conceived of the idea. You are 100% correct to say that he was not to blame for the failure rates as he was deceased before it was ever commercialized. Had he lived, he may have been able to figure out the answers to the problems. As it stands, it was Gersten who is both to be given credit for and blame for the commercial result of the driver.

MAPMAN: You're right to assume that as the frequencies get lower and wavelengths get longer the drivers behave more pistonically. You're also right to say that the Ohm F's and A's (as well as the GP Unicrns) are the only such drivers to have behaved full range. As a result, the Ohm drivers failed often because their voice coil was called on to move the entire mass of that massive driver cone ... and the power required to make the driver "wake up" and play at decent levels was just about enough to kill the VC's.

To this day the most engineering experience with this kind of driver comes from Peter Dicks and German Physiks. Together they have logged almost 20 continuous years of R&D into this driver with access to very advanced computer modeling along the way.

It is fair to say that Lincoln Walsh was the "father" of this kind of driver. I've read the patent he filed in 1964 and it reveals to me a prodigious intellect. It is also fair to say that Peter Dicks and German Physiks made this style of driver reliable, predictable, and much more efficient.

I'm sorry, Unsound, if this somehow ruffles your feathers. I didn't mean to offend you. In fact ... I didn't think it *could* offend you.
"Next: The Peter Dicks driver parts ways with the Ohm driver in several ways. First of all, it was modeled more accurately."

There is no doubt that modern (1980s and later) Computer Aided Design (CAD) technologies would provide a means of producing superior drivers, Walsh style included.

These tools were not around when Walsh conceived of the Walsh driver nor when Gersten attempted to actually realize the design. So practically, the concept was ahead of its time in terms of the ability for a manufacturer to realize it optimally. The tools and technology needed simply either did not exist or was cost prohibitive.

Credit goes to Dick and GP for applying the newer technologies needed to the problem practically once they became available. Credit also goes to John Strohbeen, though he took a different approach in the interest of value, robustness and good sound.

Apparently though, nobody has yet figured out a way to make it work in a robust and reliable manner in a single full range driver though. All modern designs either punt and introduce a second driver or are still somewhat fragile in the same way as the originals.

How do the GP Unicorns do with high SPLs compared to the Ohm Fs or As?

Also how much do they cost?

Unicorn will be able to produce over 100dB, especially with the carbon DDD option. I'm intending to get a pair for myself early next year. It's a very interesting design, unique non-horn horn loading utilizing coincident internal ports for tuning at various frequencies, etc.

Have you seen the web brochure?

John Strohbeen deserves tons of credit ... he managed to alter the design of the loudspeaker in such a way as to make it reliable ... damn near bulletproof. Furthermore, he managed to make a very enjoyable loudspeaker that has extremely compelling performance. When I was a teen these were being sold at a store in the mall and I was dumbfounded by how much different they sounded than any other HiFi I had ever encountered until then. They left a very deep impression.

I'll say, as well, that Ohm doesn't get as much attention as they deserve. I wish I saw some mainstream reviews of the stuff, as I think their speakers offer a lot for the money.