AudioCircle

Audio/Video Gear and Systems => Open Baffle Speakers => Topic started by: wisnon on 13 Oct 2012, 10:55 am

Title: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 13 Oct 2012, 10:55 am
I have not heard it but a friend who heard a demo of the prototype is excited!

http://www.rowen.ch/fr/lmt.php  ( in french)

Bad English translation:


Linear Motion turning - LMT

This mid-range/hi-frequency system establishes a completely new standard for realistic music reproduction, by exceptional dynamics, finesse, and aeries, all without any staining.

After three years of intensive development on the ROWEN LMT, a dream became reality. Mid and high frequencies are all transmitted with a virtually unlimited dynamic through a single membrane. The trigger for the implementation of this system is Mr. Markus Trachsel, a very competent person in the domain of high end audio and also owner of Sealand Multimedia AG in Lyss, Hifi Glanzmann in Bern, and moreover he is very passionate about ROWEN products.

Unlike the broadband systems such as "Air Motion Transformer" and "Manger Sound Transducer", the ROWEN LMT does not work with a deformation of the membrane. It is completely free, without mechanical suspension, powered by a double coil, powered by four very strong neodymium magnets (with a force of 140 kg!). The shape of the membrane is chosen so that it is activated only in the longitudinal direction, thus with very good stability. The absence of mechanical binding of moving parts ensures that the LMT works without colouring and with an unmatched sound neutrality.

The development team's (led by Anton Aebischer) motivation was to solve what seemed an impossibility. This commitment to quality is already demonstrated by products such as ROWEN amps, which have proven their market reputation through application of unique technologies. This motivation allows us to fully meet the requirements of music reproduction at a maximum level.
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: studiotech on 14 Oct 2012, 03:04 pm
That is an interesting variation of a linear voice coil. Thanks for posting.  Is this company making this driver available to other manufactures or just using it themselves?  I looked around their website for a bit, but did not see any loudspeaker models using it.

Greg
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 17 Oct 2012, 02:57 pm
Greg, here is more info:

http://www.6moons.com/industryfeatures/lmt/1.html

My dealer friend here in Geneva region heard the prototype and is hyped! He said its great.

The Zurich hi-end show is this weekend and we will be going, but am not sure if Rowen (Fribourg canton based) will be there. They were not last year.
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: Rocket_Ronny on 17 Oct 2012, 03:23 pm

Great info. Do you know what is the 5 octave range covered and pricing, availability?

Thanks,

Rocket_Ronny
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 17 Oct 2012, 04:12 pm
Great info. Do you know what is the 5 octave range covered and pricing, availability?

Thanks,

Rocket_Ronny

Hi Ronny,

Just got off the phone with one of the Rowen principals and got some more info. |they are very nice people who can be approached.

First off the bad news. They ONLY operate commercially in Switzerland where they have a big market share and have no immediate plans to expand outside.  They are VEY loyal to their dealer newtwork in Switzerland. Individual customers (not in neighbouring countries) can approach them from overseas to purchase and they likely will accomodate on a case by case basis. Thus, you wont soon see their LMT technology or negative output impedance amps outside Switz any time soon. I tried to talk them into exploring the possibility of OEM-ing the LMT driver with a selected US partner in the future, so that is food for thought for them.

The speakers with LMT are just being shipped now and the first dealers should be getting them today.

As to the LMT tech itself, it uses NATURAL not synthetic material and extensive testing (3 years) bears out the superiority of this approach.  It runs dipole, but is damped at the back and sound tunnelled back to the front of the speaker. It is very fast like the AMT drivers and you hear this in piano reproduction, but he claims that the extra advantage is that there is no material coloration from using synthetic material like Mylar or Kapton. Fast and airy with electrostatic like precision, but no coloration from the material used, while being warm and smoooth. Wide dispersion, ie 150 degrees in front and also in the back.

the diver is NOT physically connected, and its movement is restricted to just forward and backward linear motion...no up/down/sideways.

The driver covers the freq range from 1khz to 28kz, above which the drop is -6db, so more than enuff HF coverage.
No speaker pricing info yet....definitely no driver pricing info forthcoming in the medium term.


Here is the description for the Gallo CDT:

The four-inch drivers are separated by Gallo’s unique C.D.T. tweeter. “C.D.T.” stands for Cylindrical Diaphragm Tweeter. The C.D.T. is, of course, cylinder-shaped, providing an extremely wide dispersion pattern of 120 degrees. The tweeter is made out of a silver coated Kynar (high-tech plastic) diaphragm, with silver wires attached to each end. This assembly is wrapped around a polypropylene core that absorbs the driver’s backwave. The current is passed across the face of the driver, causing it to expand and contract, a technology similar to the piezo tweeters of yesteryear.

The C.D.T.’s surface area is more than 12 times that of a conventional one-inch dome tweeter. Despite the large surface area, the moving mass weight is lower than that of most conventional drivers, as there are no voice coils, formers or surrounds. The design allows for a great deal of output without breakup or distortion and also greatly contributes to the speakers’ large sweet spot.

Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: Telstar on 1 Nov 2012, 03:53 pm
Very interesting. I'll go listen to it once they put it in their "Absolute" line of speakers.
So far the ONLY HF transducer that completely satisfied me is the Precide Heil Kithara, with the FAL still unheard.

This LMT unfortunately has the same issue as the Heil, it cant be crossed low enough (1khz in this case, 800hz for the Kithara), which is a BAD XO point. Rowen designers seem to know how to divide the spectral range (at least in the Absolute line), so I hope for a decent subbass and a good midbass way.
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 1 Nov 2012, 04:37 pm
Actually, the Kithara is crossed at 650hz with a shallow slope and has significant energy down to 400hz!
I know the designer very well and we had a lenghty discussion about this.

"ONLY HEIL AMT has these particular drivers. The other modern copy cats and the Vintage ESS speakers use mylar and teflon which are inferior diaphragm materials. The Kithara's Heil driver is crossed at 650hz with a 12db 2nd order crossover filter, while ESS used a 24db crossover filter at 900hz. This is why the Kithara has energy down to 400hz!!!"


The LMT is in an active and passive speaker, but I cant recall the model numbers Yvo gave to me...

Are U in CH?
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: Telstar on 1 Nov 2012, 11:39 pm
Actually, the Kithara is crossed at 650hz with a shallow slope and has significant energy down to 400hz!
I know the designer very well and we had a lenghty discussion about this.

Oh I'm sorry I must have confused with the smaller tweeter, the Aulos (very good sounding, but way too inefficient for me).

The integration with the bass driver is not perfect and I dont feel the woofer is fast enough to keep up with the Heil. This is a common problem with this kind of tweeters. That's why a third way with some relatively small midrange in appropriate low-Qt loading (ideally OB) would work better. Still the 650hz XO point is not ideal (albeit better than 800, yes)

For instance, an example of a better integration MF-HF has been done in the Manger speakers, where the woofer is tracked in a special way. Pity the Kithara sounds 100 times better ;)

Quote
"ONLY HEIL AMT has these particular drivers. The other modern copy cats and the Vintage ESS speakers use mylar and teflon which are inferior diaphragm materials.

I know - they pierce my ears, both new and old ESS production.

Quote
Are U in CH?

No, in northern Italy, and a trip to south/central switzerland is very well doable.
I read the announcement from one of their bigger retailers. I'll check later next month (i think they said late november).
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 1 Nov 2012, 11:56 pm
Yes, the Manger driver goes down to 80hz, but the Heils is btter. The Kithara now has a plinth/bass diffuser that tightens up the bass further. The picture is at the website (Munich show report) at www.precide.ch

I have a pair of Syrinx and also Aulos. Both have 6.5 inch bass/mid woofers (15cm) and thay are plenty fast enough for the smller Heil tweeter that is indeed crossed at 950hz. The Aulos is about 90db efficient, the Syrinx is 91db and the Kithara is 94b. In the near future, i hopeto wire the Aulos and the Syrinx in series-Parallel and run then as a wall of sound setup. All Heils are perfectly in phase, so no issue to do that. The Aulos and Syrinx are being phased out and there are deals to be had!

There is also the new Aulos Bookshelf that looks like a classical rectangular box and will also have a sub-woofer stand as an option from early next year. Still dipole, as there is a tunnel from front to back, but to me not as airy as the original Aulos.

Heil AMT is in Morbio Inf in the Italian part of Switz.

Finally, I have no problems with the 950hz X-over as I dont hear any glitch in the Matrix. LoL

Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: Vigoon on 3 Nov 2012, 06:05 pm
...I'm living in Geneva, so please tell me if I could be of any help.... :D
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 3 Nov 2012, 08:15 pm
...I'm living in Geneva, so please tell me if I could be of any help.... :D
What part?
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: Telstar on 5 Nov 2012, 06:31 pm
...I'm living in Geneva, so please tell me if I could be of any help.... :D

http://www.rowen.ch/en/haendler.php

They list two dealers in Geneve, so if you are interested in the LMT you could aske them when they will be available to demo and report here :)
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 5 Nov 2012, 08:00 pm
http://www.rowen.ch/en/haendler.php

They list two dealers in Geneve, so if you are interested in the LMT you could aske them when they will be available to demo and report here :)

LoL

I am at one of those dealers every other weekend (a good buddy is the Manager) plus I am in contact with the Aebischers (I have been to the factory once - last year).

I meant which part of Geneva...I am in Lancy.
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: Vigoon on 5 Nov 2012, 09:40 pm
I'm living at the Servette... :D
I did not knew some members were that close!!!
Title: Re: A new tweeter is born! Linear Motion Technology (LMT)
Post by: wisnon on 5 Nov 2012, 10:24 pm
I'm living at the Servette... :D
I did not knew some members were that close!!!
The only other Swiss member I know (Rudi) is in the Zurich area..except for Srajan of course, who is near Montreaux.