Album-oriented rock (AOR, originally album-oriented radio) is a radio format created in the United States in the late 1960s that focuses on the full repertoire of rock albums and is currently associated with classic rock.
The format arose when American FM radio stations decided to play tracks by hard rock and progressive rock artists. In the mid-1970s, AOR was characterized by a layered, mellifluous sound and sophisticated production with considerable dependence on melodic hooks. By the early 1980s, research and formal programming had honed the format's commercial appeal, leading to tremendous popularity. In the early 1980s, the abbreviation AOR shifted to "album-oriented rock", meaning music in the classic rock genre recorded in the late 1960s and 1970s.
The term is also commonly conflated with "adult-oriented rock", a radio format that also uses the initialism "AOR" and covers not only album-oriented rock but also album tracks and "deep cuts" from other rock genres, such as soft rock and pop rock.
History
Freeform and progressive
The album-oriented rock radio format started with programming concepts in the 1960s. The freeform and progressive formats developed the tone for AOR playlists for much of its heyday.
In July 1964, the U.S. Federal Communications Commission (FCC) adopted a non-duplication rule prohibiting FM radio stations from running a simulcast of the programming from their AM counterparts. AM/FM affiliate station owners fought these new regulations, delaying enactment until January 1, 1967.
The freeform format in commercial radio was created to program the FM airwaves inexpensively. Programmers like Tom Donahue at KMPX in San Francisco developed stations where DJs had the freedom to play long sets of music, often covering a variety of genres. Not limited to hits or singles, DJs often played obscure or longer tracks by newer or more adventurous artists rather than those heard on Top 40 stations of the day. This new format caused albums, instead of singles, to be rock's main artistic vehicle in the 1960s and 1970s.
With a few exceptions, commercial freeform had a relatively brief life. With more listeners acquiring FM radios, it became more important for stations to attract larger market share to sell more advertising. By 1970, many of the stations were instituting programming rules with a "clock" and system of "rotation". With this shift, stations' formats in the early 1970s were now billed as progressive. However, DJs still had input over the music they played. The selection was deep and eclectic, with a range of genres.
1970s
In October 1971, WPLJ in New York began to shift its freeform progressive rock format into a tighter, hit-oriented rock format similar to what would later become known as AOR. WPLJ's parent company, ABC, installed similar formats on all of its FM stations, including KLOS in Los Angeles and WRIF in Detroit. Gordon McLendon followed suit on his stations, most infamously at WPHD in Buffalo, New York, where McLendon cut over 90% of the station's album library and pushed popular evening jock Jim Santella—whom McLendon did not like—to publicly resign. In 1973, Lee Abrams, formerly at WRIF, successfully installed a similar format, later known as SuperStars, at WQDR in Raleigh, North Carolina.