Trans-Siberian Orchestra (TSO) is a US-based band founded in 1993 by producer, composer, and lyricist Paul O'Neill, who brought together Jon Oliva and Al Pitrelli (both members of Savatage) and keyboardist and co-producer Robert Kinkel to form the core of the creative team. The band gained in popularity when they began touring in 1999 after completing their third rock opera, Beethoven's Last Night. By 2007, The Washington Post referred to them as, "a touring juggernaut" and describing their music as, "Pink Floyd, meets, The Who, meets Yes." TSO has sold more than 9 million concert tickets and over 8 million albums. The band's musical style incorporates classical, orchestral, symphonic, and progressive elements into hard rock and heavy metal.