The album was recorded after a three-year hiatus caused by a throat infection of vocalist Ian Anderson, resulting in his changed singing style. Following the unsuccessful electronic rock album Under Wraps, Crest of a Knave had the band returning to a more hard rock sound. The album was their most successful since the 1970s and the band enjoyed a resurgence on radio broadcasts, appearances in MTV specials and the airing of music videos. It was also a critical success, winning the 1989 Grammy Award for Best Hard Rock/Metal Performance Vocal or Instrumental in what was widely viewed as an upset over the favorite, Metallica's ...And Justice for All.
The album relied more heavily on Martin Barre's electric guitar than the band had since the 1970s. The style of Crest has been compared to that of Dire Straits, in part because Anderson no longer had the vocal range he once possessed (the result of recent throat surgery).
Ian Anderson later stated about the musical style of the album: "'Steel Monkey' was based around a sequencer riff, and it didn't have any flute in it. So it was yet another atypical Jethro Tull song that was a radio hit. By comparison, both 'Farm On The Freeway' and 'Budapest' are very typical Tull songs. 'Budapest' is the kind of song I like to write because it embodies a lot of different nuances which I think are subtly joined together. It sort of moves from classical to slightly bluesy to folk, and it just slips between them and you don't see the stitching."
(en.wikipedia.org/wiki/Crest_of_a_Knave)