Original Masters is a greatest hits album by Jethro Tull released under Chrysalis Records in 1985. It was the band's third such effort, the first two being M.U. - The Best of Jethro Tull and Repeat - The Best of Jethro Tull - Vol II. Although the compilation was released in 1985, it does not include material released after 1977. It is worth noting that the first two compilations had already covered material released exclusively up to 1977 and Original Masters rehashes much of their material. However, Original Masters has different takes or mixes of some songs than those commonly heard. The reason is that many of the selections are early promotional versions that were sent to radio stations.The version of Aqualung included here has an entirely different recording of the middle acoustic section, which is allegedly the same used on the Quad release of Aqualung in the 1970s.