Definition and characteristics
The term "progressive rock" is synonymous with "art rock", "classical rock" and "symphonic rock". Historically, "art rock" has been used to describe at least two related, but distinct, types of rock music. The first is progressive rock as it is generally understood, while the second usage refers to groups who rejected psychedelia and the hippie counterculture in favour of a modernist, avant-garde approach.[nb 1] Similarities between the two terms are that they both describe a mostly British attempt to elevate rock music to new levels of artistic credibility. However, art rock is more likely to have experimental or avant-garde influences. "Prog" was devised in the 1990s as a shorthand term, but later became a transferable adjective, also suggesting a wider palette than that drawn on by the most popular 1970s bands.
Progressive rock is varied and is based on fusions of styles, approaches and genres, tapping into broader cultural resonances that connect to avant-garde art, classical music and folk music, performance and the moving image. Although a unidirectional English "progressive" style emerged in the late 1960s, by 1967, progressive rock had come to constitute a diversity of loosely associated style codes. When the "progressive" label arrived, the music was dubbed "progressive pop" before it was called "progressive rock",[nb 2] with the term "progressive" referring to the wide range of attempts to break with standard pop music formula. A number of additional factors contributed to the acquired "progressive" label: lyrics were more poetic; technology was harnessed for new sounds; music approached the condition of "art"; some harmonic language was imported from jazz and 19th-century classical music; the album format overtook singles; and the studio, rather than the stage, became the focus of musical activity, which often involved creating music for listening, not dancing.
One of the best ways to define progressive rock is that it is a heterogeneous and troublesome genre – a formulation that becomes clear the moment we leave behind characterizations based only on the most visible bands of the early to mid-1970s
– Paul Hegarty and Martin Halliwell
Critics of the genre often limit its scope to a stereotype of long solos, overlong albums, fantasy lyrics, grandiose stage sets and costumes, and an obsessive dedication to technical skill. While progressive rock is often cited for its merging of high culture and low culture, few artists incorporated literal classical themes in their work to any great degree, and only a handful of groups purposely emulated or referenced classical music. Writer Emily Robinson says that the narrowed definition of "progressive rock" was a measure against the term's loose application in the late 1960s, when it was "applied to everyone from Bob Dylan to the Rolling Stones". Debate over the genre's criterion continued to the 2010s, particularly on Internet forums dedicated to prog.
According to musicologists Paul Hegarty and Martin Halliwell, Bill Martin and Edward Macan authored major books about prog rock while "effectively accept[ing] the characterization of progressive rock offered by its critics. ... they each do so largely unconsciously." Academic John S. Cotner contests Macan's view that progressive rock cannot exist without the continuous and overt assimilation of classical music into rock. Author Kevin Holm-Hudson agrees that "progressive rock is a style far more diverse than what is heard from its mainstream groups and what is implied by unsympathetic critics."
In early references to the music, "progressive" was partly related to progressive politics, but those connotations were lost during the 1970s. On "progressive music", Holm-Hudson writes that it "moves continuously between explicit and implicit references to genres and strategies derived not only from European art music, but other cultural domains (such as East Indian, Celtic, folk, and African) and hence involves a continuous aesthetic movement between formalism and eclecticism."[nb 3] Cotner also says that progressive rock incorporates both formal and eclectic elements, "It consists of a combination of factors – some of them intramusical ("within"), others extramusical or social ("without")."
One way of conceptualising rock and roll in relation to "progressive music" is that progressive music pushed the genre into greater complexity while retracing the roots of romantic and classical music. Sociologist Paul Willis believes: "We must never be in doubt that 'progressive' music followed rock 'n' roll, and that it could not have been any other way. We can see rock 'n' roll as a deconstruction and 'progressive' music as a reconstruction." Author Will Romano states that "rock itself can be interpreted as a progressive idea ... Ironically, and quite paradoxically, 'progressive rock', the classic era of the late 1960s through the mid- and late 1970s, introduces not only the explosive and exploratory sounds of technology ... but traditional music forms (classical and European folk) and (often) a pastiche compositional style and artificial constructs (concept albums) which suggests postmodernism."