From Wikipedia:
Lofgren had formed the band originally with bassist George Daly and drummer Bob Berberich, and the group played in venues throughout the Washington D.C. area before going to California. Daly left the band early on to become a Columbia Records A & R Executive and was replaced by bassist Bob Gordon, who remained through the release of four critically acclaimed albums of catchy, hard rock, from 1971 to 1974, with guitar as Lofgren's primary instrument. The single "White Lies" got heavy airplay on Washington, D.C.-area radio. Lofgren wrote the majority of the group's songs, and often shared vocal duties with other members of the band (primarily drummer Bob Berberich). After the second album Nils added brother Tom Lofgren as a rhythm guitarist. Grin failed to hit the big time, and were released by their record company.
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