Re: Directional Mic - using only aural tubes

A prototype of that last one should cost you less than $20 at Home Depot.

But hang on a sec.  Check it for function at home first, then check with your
local materials experts before bringing it to the factory.

It sounds like you're working in a munitions factory.  In a place like that,
I'd be hesitant to use something like the flexible clear vinyl tubing that
first came to mind, not because it's conductive, but because it's so
nonconductive that it can hold and carry a static charge from the factory where
it was made to your factory.  Unrolling a package will sometimes cause the hair
on your arm to stand up; probably not a good thing where you work.  

I think rigid, opaque (filled) pvc tubing and pipe may be conductive enough to
bleed off static charge, but it's probably not _guaranteed_ to do so.  Again,
check with your local experts.

-Mike-