RMBP Dual Microphones.

[Southernboyj]

I know the microphones are hidden but does anyone know where?

 

[Stetrain]

Beneath the left speaker grill.

If you scroll down to the "Audio and Visual" section on this page:

http://www.apple.com/macbook-pro/features/

and click the "Dual Mics" button the graphic shows where they are. iFixit's teardown found them in that location as well.