Progressive rock music has its roots in the mid 1960's psychedelic cultural phenomena. During that time the British Invasion and folk-rock bands began to expand the sonic possibilities of their music. These groups slowly started to abandon the concise verse-chorus-verse patterns of rock & roll, and moved towards fluid, free-form oriented song structures. Just as important was the incorporation of elements from Indian and Eastern music. Along them the principles of free-form jazz were included to the psychedelic sound, emphasising spontaneous emotions over calculated and estimated compositional constructions. Experimenting with new studio technology, electronically altering instruments and voices, was a part of this altered approach as well. Acid rock groups like THE JIMI HENDRIX EXPERIENCE and CREAM stand as descriptive and popular examples of the path from psychedelic sunshine pop towards a more aggressive and distinct rock expression, in particular showcased in their improvised live performances.
The boundary dividing the "Experimental" and "Progressive" classification is a thin and at times contested one for this era. The pioneering psychedelic progressive rock bands to be found at www.progarchives.com will in most cases be found in the Proto-Prog section of the site. Amongst these pioneering outfits are acts like THE BEATLES, JEFFERSON AIRPLANE AND VANILLA FUDGE. Artists such as PINK FLOYD will not be found there though, as their career extended well beyond these first, formative years.
Psychedelic progressive rock music may contain the elements previously described in varying combinations, but the artistic perspective of progressive rock is another factor. Some psychedelic rock bands stuck to the mid 1960's beat rock style in purist form, not partaking in the experimental development of the impressionistic possibilities of psychedelic rock music others spearheaded. The evolution of the psychedelic depth within a progressive context could be seen for instance in the 1960's recordings of ARCADIUM and BABY GRANDMOTHERS. One good example of early 70's Continental European progressive psychedelic rock is the album by AHORA MAZDA, and from Britain JADE WARRIOR's early efforts fuse psychedelic rock and ethnic music. Current artists exploring the vintage 60's/70's style and sound are acts like THE SPACIOUS MINDS and ACID MOTHER'S TEMPLE.
The entire Western pop culture scene was influenced by the psychedelic culture to some extent, including other prog genres such as Prog Folk. In Germany, artists influenced by the British psychedelic movement formed their own genre called KRAUTROCK. The pioneering early 70's bands in this genre represent the progressive acid rock sound of Germany, experimenting with long instrumental improvisations, emphasizing the use of psychedelic effects and weird electronic sounds. Some examples are artists like AMON DÜÜL, ASH RA TEMPEL, CAN, GÄA, NECRONOMICON and YATHA SIDHRA. The PROGRESSIVE ELECTRONIC style emerged from Krautrock. Some of the most influential artists of this genre, such as TANGERINE DREAM and KLAUS SCHULZE, explored a distinct psychedelic musical style at first, which was influential for the development of the "space rock" sound
