by Alex HendersonLike so many risk takers, Jethro Tull have had their share of both admirers and detractors over the years. To their admirers, Ian Anderson and his colleagues did a lot to expand rock's boundaries; to their detractors, they epitomized progressive rock's excesses (especially during the '70s) and were a prime example of why the punk movement was needed. It's no secret that Tull -- like Yes, Pink Floyd, Genesis, and Emerson, Lake & Palmer -- were influenced by European classical music (as well as British folk, Celtic music, blues, and jazz). So it comes as no surprise that on this live two-CD set, Anderson celebrates that Euro-classical influence by joining forces with a large orchestra. Ian Anderson Plays the Orchestral Jethro Tull documents a December 2004 concert in Mannheim, Germany, where Anderson (lead vocals, flute, acoustic guitar) is joined by the Neue Philharmonie Frankfurt."Aqualung,""Locomotive Breath,""My God," and other Tull favorites receive the orchestral treatment, as do Johann Sebastian Bach's"Bourée" and the European Christmas carol"God Rest Ye, Merry Gentlemen." The arrangements are not only tasteful -- they sound perfectly natural given the classical influence that has been a part of Anderson's work for so long. Of course, these performances aren't classical music in the strict sense -- even if one of the pieces is by Bach. Rock is still Anderson's foundation, which doesn't mean that he cannot use some of the Euro-classical vocabulary to his creative advantage. Ian Anderson Plays the Orchestral Jethro Tull is unlikely to win over Anderson's critics, but for prog rock diehards, this double CD (which is also available as a two-DVD set) is a pleasing (if short of essential) demonstration of Tull's ability to interact with the orchestral/classical world.