[Boatanchors] Crystal Headphones

[Duane Fischer, W8DBF]

Hi All,

Just curious.

When were crystal headphones first introduced? By whom? And why?

Did they serve a specific purpose that other headphones of that era did not, 
perhaps could not?

When were crystal headphones abandoned in favor of carbon headphones or 
whatever? What replaced them? Who made them? And why?

Given a vote, what type of headphones would you select as the best all 
around for voice, music and Code?

Thanks!

FYI: Unrelated. The main computers that keep 'mailman.qth.net' operating 
also keep a running count on what subscriber posts the most each month, 
among other topics of fascinating interest. Should we post the top five 
subscribers who qualify each month? (Chuckle)

Duane Fischer, W8DBF - WPE8CXO
E-Mail: dfischer at usol.com
Hallicrafters web site: www.w9wze.net
HHRP web site: hhrp.w9wze.net