Why do throat mics almost always have 2 elements?

[theycallmevirgo]

Most things like this

https://www.coderedheadsets.com/Assault-MOD-Waterproof-Tactical-Throat-Mic-p/assault-mod-wp.htm

generally have 2 transducers. Why? If for phased array noise cancellation, can someone give a broad outline of the "summing" circuit?

 

[tech99]

I would guess that the two transducers are connected in series opposition. As both are subject to ambient noise, it will be cancelled. But only one transcuder is coupled to the vocal cords, to that signal is not cancelled.

 

[Tom.G]

Try this search. Noise cancelling does not seem to be needed.The skin at the throat being much thicker than the eardrums, likely doesn't vibrate nearly as much... and some sites describe a throat mic as a vibration sensor.

https://www.google.com/search?&q=throat+mics