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it developed from psychedelic rock and originated, similarly to art rock, as an attempt to give greater artistic weight and credibility to rock music. bands abandoned the short pop single in favor of instrumentation and compositional techniques more frequently associated with jazz or classical music in an effort to give rock music the same level of musical sophistication and critical respect. songs were replaced by musical suites that often stretched to 20 or 40 minutes in length and contained symphonic influences, extended musical themes, fantasy-like ambience and lyrics, and complex orchestrations.
