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EMS LB12EX field coil full range driver by Catherine Fertin

Posted on March 29, 2008 at 19:08:27
Does anyone have experiences with this 12" field coil speaker?


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RE: EMS LB12EX field coil full range driver by Catherine Fertin, posted on March 21, 2009 at 01:52:33

Posts: 250
Joined: November 17, 2007
bump for this


RE: EMS LB12EX field coil full range driver by Catherine Fertin, posted on March 24, 2009 at 17:10:46
The *

Try contacting the Fertin rep in Canada, he has them in a open baffle.


RE: EMS LB12EX field coil full range driver by Catherine Fertin, posted on August 25, 2009 at 04:06:45

Posts: 4
Joined: August 25, 2009

Just to let you know the new web site of Catherine Fertin (Electro Magnet Speaker : www.emspeaker.com

English pages are in progress.

LB12EX is a very strong and fine fullrange loudspeaker. At home, mounted in a quiet simple cabinet, it sounds great, with very impressive bass, a crystal clear medium part, and very analityc high frequencies, although they are franckly cutted at 15 kHz. Then, the option to add a supertweeter is worth to try (I manage to in a close future).
What is absolutely interesting with is the very large focus, then the concept of sweet focus point is a bit abstraction with this kind of speaker.
Electromagnetic helps to obtain an accurate phase and global sound considering cabinet, possible other speakers and room conditions. The lower the amperes, deeper the bass and softer the high frequencies.
Worth more than a listen...


RE: EMS LB12EX field coil full range driver by Catherine Fertin, posted on August 30, 2009 at 02:19:13

Posts: 27
Location: Copenhagen
Joined: February 2, 2009

Thanks for your description of the EMS LB-12EX.

I have been very curious since I first read about this driver.

The field coil magnet system is said to have to have some sonically advantages over other magnet systems, if well constructed.

For some years I have been using Altec Duplex 605B with custom made cross overs, together with a low power 2A3 SE amplifier.

However I much like the idea of a "true" full range driver, with no cross over at all, eventually assisted by a super tweeter above 10 or 15 KHz. I have fine experiences with Fostex T825A vintage horn tweeters in this respect.

Even though speaker quality is such a subjective matter, would you able to go a little more in depth regarding the rendering characteristics of the LB-12EX?

Do you know the "sound" of the Altec Duplex'es, or maybe Tannoy Dual Concentric 15" drivers? Would the LB-12EX have the same degree of resolution in the lower / upper midrange and treble area?

Of course the best thing will be to visit EMS and conduct a listening test session, but I cannot find the time at the moment.

Thanks in advance for your inputs.



RE: EMS LB12EX field coil full range driver by Catherine Fertin, posted on August 30, 2009 at 11:06:43

Posts: 4
Joined: August 25, 2009
Hello Thomas,

Thanks for your interest in our product. My english is a bit bad, but I hope you'll understand me well. Sorry if words are not so clear as they could.

LB12EX (and LB12, in a minor note as well) presents some advantage compared to alnico or other well designed LB. Firstly, it's very linear, without any usual accident in the critical area of 1500-11000 Hz. Another point is the ability to greatly enhance the result using well conceived stabilized power, or even battery. In the other hand, the level of performance is constant in times, compared to alnico.

We have developed a technology with no standard values applied to magnetic fields. In fact, the absolute values are equally displayed into the entire mobil elements and match only as a global one. If you measure at a particular point, you will not find the value which is considered by industry as the optimal one. We discovered that this kind of measure is not suitable with a stable performance, as the theorical ideal value changes according to the movements of the mobil elements, causing very short moments when the membrane is not well driven, due to the coil moving out of the optimal magnetic fluid. With our technology, the coil is ever moving in optimal conditions, not matter its position (in normal conditions, of course, our drivers are not sono pa systems).
We have test a lot of drivers from other brands, and none uses our technology. Fortunately (for us), the great brands are buzy to develop new materials, new up to date look to suit marketing demand. Then, we have a slightly technological advance which make the difference. Maybe another developer : Janus by François Deminiere, is working in a similar way... I don't meet him yet, then I'm not sure : http://fdacoustic.fr/JANUS50_ecoute.htm

the technical datas are here : http://www.emspeaker.com/LB12EX_fiche_technique.pdf

Well, I know about Tannoy dual Concentric drivers (all). EMS LB12EX delivers a slightly more stable 3D image, more dynamic live sound and (by consequence ?) a very much more analityc power.
Thanks to their good tweeter, Tannoy's are a bit softer and match well with amps of the highest level. Curiously, I've heard enhancement with dynamic amps like Creeks ones or Lavardin, probably because of their high dynamic in the mid low range. A characteristic which can be favored by high end 300B amps.
But if you want to immediately hear the difference between a Bösendorfer and a Yamaha, then you will have to choice the LB12.

Vantage Altec Duplex 605B are old school drivers at their finest, in my opinion. Coupled with an amp like yours, it's a very interesting marriage. Well, LB12EX is another completely different solution. I have no idea what could be the result with a horn Fostex T825A, but talking about measures, it could be a very suitable association (chord and efficiency).

I can ask to Katy Fertin if you need more accurate informations.


RE: EMS LB12EX field coil full range driver by Catherine Fertin, posted on July 17, 2015 at 10:29:57

Posts: 600
Joined: March 12, 2005
can you comment a little more about the difference between the LB12 vs LB12EX?
Also, what is your opinion about the best enclosure: an open baffle or a TQWT and the possible frequency extention for both?


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