Curved Air - Back Street Luv (1971) 

Curved Air are an English progressive rock group formed in 1970 by musicians from mixed artistic backgrounds, including classical, folk, and electronic sound. The resulting sound of the band was a mixture of progressive rock, folk rock, and fusion with classical elements. Along with High Tide and East of Eden, Curved Air were one of the first rock bands after It's a Beautiful Day, The Flock and the United States of America to feature a violin. Curved Air released eight studio albums, the first three of which broke the UK Top 20, and had a hit single with "Back Street Luv" (1971) which reached number 4 in the UK Singles Chart.