According to wikipedia, the origins of pop music can be traced back in Napoli Italy, in 1679, when Alessandro Scarlatti composed his first opera, or even earlier, when Francesco Provenzale coined the musical language that Scarlatti popularized: light, lively and catchy. They placed the emphasis on arias, clearly separated from the “recitativo”, and grounded the arias on a strong sense of rhythm and melody.
An important turning point for popular music was the “speed war” of the late 1940s: a battle among the record labels of the day to enforce their own standard. The dominating format, the 10 inches (25 cm) 78 (rpm) disc, was challenged in 1948 by the new 33 ? rpm 12 inches (30 cm), and then in 1949 by the 45 rpm 7 inches (18 cm). Next came the switch in the material records were made of, from shellac to vinyl; the new component, combined with the slow 33 ? rpm playing speed, allowed recordings to extend their duration further than was previously possible, and gave birth to the long playing record (LP). Changes continued with the invention of the multitrack tape recorder, permitting completely electronic studio recordings for the first time, and the advent of stereophonic sound in 1958.
The first major pop stars as such were the crooners of the 1930s and ’40s. Bing Crosby sold millions of records, as did Frank Sinatra (arguably the first modern pop star, with screaming teenage female fans - the bobbysoxers), and in Britain, Al Bowly.
Curiously, pop music charts as such didn’t exist until 1952, when the first Top Twenty was recorded. It came at an interesting time, as “teenagers” really came into being.
