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I asked Alex who got those tweeter from him and he said that it was Stavros Danos from Cyprus. So, it was the Greek guy that we have meet before on the pages of my site:
http://www.goodsoundclub.com/Forums/ShowPost.aspx?postID=12129#12129
It looks like he formed a new company somewhere within the Cyprus:
http://www.aries-cerat.eu/
If you click on the 5th tab then you arrive to the “Contendo Reference” page. Let look what we have in there:
The Alex’s ribbon tweeter with amorphous core transformers and fast opening horn with continued its flare back. This is good. For claimed unparalleled performance I would like to see the “thinner” version of Alex ribbon but we do not know what MF driver they use and where they cross it. Let presume that they did the right thing for what they did optimized the tweeter to work fine with their MF.
The Mid range channel:
“Using a highest quality compression driver, with 4’ titanium diagram as our mid frequency reproducer ,requires nothing less than a perfect flared horn. We use a 350hz tractrix horn, o load the driver from 700 to 3000hz, and taking the flare back to 360o building the horn in our solid wood bullet shape enclosure ,we completely removed diffraction as an issue. Efficiency is 118db/W and is attenuated via a impedance matching transformer to 104db/w”
OK, I see, they use the MF up to 3K and then plug in the tweeter. This is a big mistake in my mind as the ribbon tweeter does not do too well tonally in MF. Again, in my mind and opinion of the Cyprus folks might be different. I do not care about tonal quality of ANY ribbon and I would like ribbons to be used at the very top, over 8-9K where there is little or no tone. There is a positive side in what Cyprus guys did. With 3K of crossover point the negative aspect of sound deriving from the vertical offset of the MF will be substantially minimized and masked out by the tweeter output.
The Midbass channel as they call. I call it the Upperbass channel.
“Most horn speakers, use direct radiating drivers for midbass reproduction. We feel that anything less that a hornloaded driver would compromise the total project. Midbass is the base of the music, in all genres. In order to cover the 110 to 700hz range we use a full size round tractrix horn, loaded with a powerfull ultralight 8in driver,with a super strong motor and a total moving mass of just 13gr , giving unbelievable detailed and defined midbass . The tractrix flare also continues at 360deg ,and is build in a massive wooden bullet shape enclosure, in order to perfectrly terminate the horn flare, so that diffraction is not an issue here as well. Efficiency is an astonishingly 115db/w and is attenuated via an impedance matching transformer to 104db/w .No direct driver is capable of delivering the sheer impact, detail and energy and that horn delivers in an ease. The midbass horn enclosure measures 120cm in diameter “
I would question if the conical fare on the back make any indifference for Upperbass but it certainly goes alone with the entire speaker design. There is something fishy in there. If the horn it tractrix then with throat of 3-5” it will do here and there no more than 6dB gain. They claim 115dB sensitivity that means that they have 109dB driver in there. Well, it would be possible, unlikely but possible to make 8” driver that will push 109dB but it would be very upper range driver. They have 100Hz horn, it means that the primary open air resonance of their driver somewhere around 80-90Hz. The 90Hz 8” driver that is able to do 109dB shall have 20 inch excursion. The pressure of driver is surface by excursion. If they have 8” driver that able to do 100Hz then can you imagine how far it shell excerpt in order to press 109dB. Well, at least I do not know such drivers…. It would be possible to hit that number if they have 8” driver blowing into 1” trout and super long exponential hold but it is not the case with the Cyprus speaker. Anyhow, regardless the numbers that I do not believe the fact that they went for full 42” horn and 100Hz is a good sign.
The bass module that they have – dual 15” sealed boxes with own amplification is fine. Of close I am not wild about the class D output stage but the fact that they went for own amp that meant to be used with their speaker I find is very stimulating.
I would not propose how this speaker would sound. In my estimation, even it has some things that I do not like but I sound the design is well balanced and one of the few examples of contemporary rational thinking. Considering what those Cyprus folks did in the past and some other development in the rigion it looks like Greece is becoming a new micro-epicenter of horn building jointing USA, Germany and France.
The Cat
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