Allen was an avid guitarist with a deep appreciation for blues and rock music. He collected a large number of guitars, including instruments owned by iconic musicians.

Allen formed his own band, 'Paul Allen and the Underthinkers,' where he played lead guitar. The band performed at various events and venues, showcasing Allen's musical talent.

Paul Allen and the Underthinkers released their debut album, 'Everywhere at Once.' The album featured Allen's guitar playing and songwriting and reflected his musical influences.

Allen frequently used his band's performances to raise money for charitable causes. He combined his passion for music with his philanthropic efforts.