In the early years of jazz, the guitar was an impractical instrument, nursed primarily by street-comer blues and gospel singers, whom it suited perfectly.

In those days before the microphone, when band vocalists used megaphones to make themselves heard, it took the metallic plunk of the banjo to penetrate the roar of horns and thunder of drums. When microphones replaced amplification cones in the mid-Twenties, allowing audio engineers to alter the balance of sound during actual performance, the door was opened for subtle instruments and weak-voiced singers.

Any discussion of a link between jazz and technology inevitably leads to the guitar, which gave the music its first electronic sound, and to Charlie Christian, who pioneered the use of the amplified guitar.