The album 'The Great American Soulbook' was released in 2009 by Tower of Power, marking their twentieth studio album. The project was produced by saxophonist and founder Emilio Castillo, and was recorded between 2008 and 2009 at various studios in California.
The record pays homage to classic soul and R&B hits from the 1960s and 1970s, including covers of artists such as James Brown, Otis Redding, and The Temptations. The band maintains its signature horn-driven funk sound, but with a focus on iconic songs of the genre.
The album was released under the independent label Top Pop Records, founded by Castillo himself. Although it did not achieve major chart positions, it was well received by the band's followers and critics for its faithfulness to the original versions and the energetic performance of Tower of Power.