Advantages of beryllium?


Can someone please explain the advantages of beryllium drivers over titanium or aluminum?

Also, how concerning are health risks associated with beryllium?

many thanks for your input. 
defiantboomerang
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Does seem one poster has no idea what a TAD driver is  http://www.technicalaudiodevices.com/pro-hf-units/  and he seems to suggest vintage doesn't perform as well as modern I suggest he point me towards a BE equipped modern driver with better specs than a TAD? 
kosst :

Sounds way too much like work. Buy whatever you’d like to listen to, but I’ve never seen specs or heard a micro-motor tweet perform as well as mid-grade tweets from SB, ScanSpeak, Seas or even Peerless.

There is a popular ring radiator from ScanSpeak ScanSpeak Discovery R2604/8320 (and a relatively lesser Peerless variant) that has been used by Magico, YG, Krell and Sonus Faber. I put that tweeter against any micro motor tweeter I’ve ever heard.

Also, the ScanSpeak Be that is the basis for the current Magico Be/Graphene tweeter is also far better sounding and measuring.

Best,


E