Focus - Focus At The Rainbow [Japan Ed. Live] (1973)

At the Rainbow (re-released as Live at the Rainbow) is the first live album from the Dutch rock band Focus, released in October 1973 on Imperial Records. The album was recorded at the Rainbow Theatre in London on 5 May 1973 by The Pye Mobile Unit, recording engineer Alan Perkins. A studio album was initially slated for release, but it was shelved due to disagreements within the band. (An album compiled from the tapes of these sessions was later released with the title Ship of Memories.) At the Rainbow was released instead.
(en.wikipedia.org/wiki/At_the_Rainbow)

The instrumental rockers of the early '70s never were any good at dulling down their musical expertise; and, indeed, it's only a matter of seconds into their first and only live release -- Live at the Rainbow -- until one realizes just how talented Focus were. Jan Akkerman, named "World's Best Guitarist" by Melody Maker in 1973 ahead of Eric Clapton and others, was amazingly on form in this performance. Thijs Van Leer, chief songwriter and performer in the band, showcased his talents on flute, vocals, and organ with unparalleled finesse. Bert Ruiter knocked out his basslines tight to Pierre Van Der Linden's drums, undoubtedly two of the finest players on their respective instruments. It would be so easy to go off on a tangent explaining the mastery that Focus had musically; suffice to say, however, the bands technical proficiency is rarely matched in the world of rock. Live at the Rainbow featured some of the band's best and most well known tracks: "Sylvia," "Hocus Pocus," "Focus II," and so on. Although much of the content sticks closely to its original studio form (12-minute tracks were regular on studio albums), with maybe an extra solo or two thrown in for good measure, a few songs host drastic changes. "Hocus Pocus," for example, is almost unrecognizable. This live version is multiple times faster than its studio counterpart -- those familiar with only the studio version are certainly in for a shock! Throughout the album the performance is simply astonishing. Live at the Rainbow is a fine purchase for any Focus fan, or, indeed, anyone looking for a band with a good degree of originality and musical ability.
(allmusic.com/album/focus-at-the-rainbow-mw0000455197)