LP record (long-playing vinyl record)

An LP (long-play) record is a 33⅓ rpm vinyl disc that stores analog sound in microgrooves. This article explains its form, history, playback, manufacture, uses, and how it differs from other formats.

Overview

An LP record, short for long-playing record, is a vinyl disc designed to carry analog audio in continuous grooves. The standard speed for an LP is 33⅓ revolutions per minute (rpm). Most LPs are produced in two common diameters—12 inches and 10 inches—and are divided into two sides, traditionally called Side A and Side B. A turntable spins the disc while a tonearm lowers a stylus (needle) into the groove; the stylus tracks variations in the groove walls and converts them into an electrical signal that is amplified into sound.

Physical characteristics and playback

LPs use "microgroove" cutting, with closely spaced spiral grooves etched into a vinyl surface. In stereophonic LPs the groove encodes two channels by modulating the groove walls so that each wall carries information for one channel (the 45/45 system). Typical playback requires a turntable with appropriate speed control and a cartridge whose stylus geometry matches the groove design. The total playing time of an LP varies with groove spacing and loudness but commonly provides roughly twenty to twenty-five minutes per side on a 12-inch disc.

History and development

The LP format was introduced commercially in 1948, allowing much longer uninterrupted playing time than the earlier 78 rpm shellac records. Its adoption reshaped the music industry by making the long-form album a practical medium for classical works, jazz, and later popular albums. Stereophonic LPs became widespread in the late 1950s, and for decades vinyl LPs were the dominant consumer format until magnetic tape cassettes and, later, optical compact discs offered different advantages in convenience, portability, and durability.

Manufacture, care and limitations

Making an LP starts with cutting a master lacquer, producing metal stampers, and pressing heated vinyl into the stamped mould. LPs are durable but subject to surface noise, clicks, pops, wear from repeated playback, and warping if stored improperly. Proper handling, storage in sleeves, and routine cleaning can reduce noise and prolong life. Audiophiles often attend to cartridge alignment, tracking force, and anti-skate to minimize wear and extract the best sound.

Uses, cultural role and notable distinctions

Beyond playback, the LP has cultural significance: album sequencing, artwork, and liner notes became artistic components tied to the format. DJs use LPs for mixing and scratching, while collectors prize original pressings and limited editions. Technically, an LP is an analog format; listeners often describe its sound as "warm" due to harmonic behavior and analog distortion, while digital formats offer advantages in signal-to-noise ratio and resistance to physical degradation.