Re: Απάντηση: Κατασκευή super tweeter.
http://www.focal-fr.com/catalogue-do...files/1172.pdf
The Focal Utopia TBe is a high efficiency tweeter with a 25 mm lightweight pure beryllium inverted dome. Beryllium's density is 2.5 times lower than titanium and 1.5 times lower than aluminium while its rigidity is 3 times higher than titanium and 5 times superior to aluminium. Which means that for a dome of identical mass, a beryllium version is 7 times more rigid than one made of titanium or aluminium - which have similar rigidity for a given mass. Moreover, the velocity of sound in a beryllium dome is 3 times faster than a titanium version and 2.5 times faster than aluminium. However, the manufacturing of beryllium remains very difficult and its production has been limited to just three countries: the United States, France and Russia. To date, Great Britain, Germany and Japan do not manufacture pure beryllium, rather using it in the form of an alloy. Beryllium is an excellent high-tech metal - the only metal able to scratch glass - it is only used in strategic applications in the aeronautical and military industries and consequently, its unique characteristics make it extraordinarily expensive, much more than gold and nearly 100 times that of titanium. And the result is an outstandingly detailed loudspeaker which extends to nearly 40 KHz while maintaining a perfect impulse response.
http://www.humblehomemadehifi.com/Humble_Statement.html