Final answer:
Elvis Presley is the crooner known for developing a conversational style with the microphone, blending various musical styles which led to his unique sound.
Step-by-step explanation:
A crooner who developed a conversational style with the microphone was Elvis Presley. He was an influential figure in the music industry and a pioneer in blending various musical styles to create a unique sound. Presley's talent in fusing gospel, blues, bluegrass, country, western, and R&B styles helped him to stand out among the artists of his time.
His conversational style of singing allowed him to connect with audiences in a more intimate and personal way.