Opera and Broadway are not alike...
They use microphones in broadway too...
Opera requires that the singer projects over a live orchestra using resonance and volume produced by breathe support and their own acoustical possibilities. The only instances in which an opera uses a microphone would be a recorded broadcast or concert amphitheater event in which the acoustics do not lend themselves for unamplified singing.

Anyway, here is a link

/watch?v=iy4h-rbhT1A

Oh and disclaimer, I am looking a mess in it as I thought silly to put on my face just to sing in my closet/bathroom, but the pics I used in my acapella of Emotions I posted some days show I can clean up and look decent.