Frank Diez is considered one of the most outstanding European blues guitarists. He has played a fundamental part in German rock history since the early seventies. Diez performs internationally as a stage and studio artist. Moreover, he is the only German musician to has played in sessions and concerts with rock stars such as Jimi Hendrix, Chuck Berry and Little Richard. He has also worked with Atlantis, Randy Pie, Ihre Kinder, Snowball, Emergency, Konstantin Wecker, Eric Burdon, Alex Conti, Tom Principato and Miller Anderson.

Diez was a founding member of the Peter Maffay Band and was its producer/guitarist until 2004 — a stint of thirty years. Today he concentrates on projects with other artists and his own band. Frank Diez uses Stark amps exclusively, both live and in the studio.