How does a shotgun mic work?

[Englebert]

I was wondering: they might not be of much use for a home recordist but just for the sake of it, what is the design principle behind shotgun microphones?

I don´t think Harveys big mic thread covered this one... I did a search, but didn´t find anything - well, except a rather amusing thread about recording farts, but that´s another story...

 

[Krakit]

Shotguns are super hyper cardiod mics that utilize side vents and a pickup in the center of a longer tube to capture sounds from a distance. The freq responce for these mics are limted so they don't get a lot of use outside of long distance recording, usually for spoken voice.

Carl