Since the invention of sound-recording technology by Thomas Edison (1847–1931) in the 1800s, people have looked for new and better ways to bring recorded sound to mass audiences. Before compact discs, audio cassettes and MP3 files, the long-playing record (LP) was the main way Baby Boomers heard recorded music.
During the first half of the twentieth century, the celluloid 78-rpm record - spinning on a turntable 78 times, or revolutions, per minute - was the major way people heard recorded music. But the 78-rpm record had a number of drawbacks: It could only hold a few minutes worth of music on each side, it was heavy, and it broke easily. Peter Goldmark (1906–1977), working for Columbia Records, developed the LP in 1948. He overcame the 78's limitations in two ways. First, he lowered the speed of the recording to 33 1/3 revolutions per minute. Second, he squeezed more and smaller grooves onto each side of the record so that more sound could fit on each side of the disc. Those grooves would reach more than a kilometre if stretched out in a straight line. Made of vinyl, the LP also required a diamond needle to play the records, which resulted in improved sound. The LP was immediately hailed by classical music lovers because the longer pieces of classical music could now be heard in a mostly uninterrupted format.
By the end of the 1950s, the LP had become the dominant form for recorded music, and it changed the face of popular music in many ways. The LP also improved the sound quality of recordings, lasted longer than 78s, were less prone to breaking, and were cheaper to produce. The LP allowed allowed musicians to experiment with longer works, including related songs on a single disc. Using the same technology, 45-rpm singles (developed at the same time as the LP) and EPs (extended play, containing two songs per side) were introduced for recordings containing one or two songs per side. These were very popular as they were much cheaper than LPs and generally contained the best songs from an LP.
By the 1960s, rock and roll musicians in particular were using the extended format to produce concept albums, the most famous of which was Sgt. Pepper's Lonely Hearts Club Band (1967) by the Beatles. In the late 1960s, FM disc jockeys preferred to play songs from LPs rather than from 45-rpm singles. Although the arrival of the CD in 1982 seemed to spell the end of the LP, and while most people now prefer CDs, some people still listen to their old LPs. Some new recordings, particularly those used by DJs at nightclubs, continue to be released in LP format, a testament to the enduring appeal of this Baby Boomer era technology.
