The Cobalt 806S’ bass/midrange
driver is 165mm in diameter, and has a
triple-layer ‘W’ cone. The outer layers
of the cone are both fibreglass, but of
different types, while the inner layer is a
lightweight foam material. In principle,
the construction is very like that of a
surfboard. (JMLab calls this a ‘W’ cone
because the French word for ‘glass’ is
‘verre’, and the letters VV [Verre-Verre]
resemble the letter W. I have always
thought this was a rotten acronym, but
I guess you couldn’t pronounce ‘VFV’
in either French or English!). Although
it’s rated at 165mm, the Theile-Small
diameter is 133mm for an effective cone
area (ECA) of 139cm2. JMLab claims its ‘W’ cones are lighter and stiffer
than cones made from either paper or polypropylene, enabling superior
performance.