Sven-Ingvars is a Swedish pop/rock group from Slottsbron, Sweden. The band was formed in 1956 by Sven Svärd (drums), Ingvar Karlsson (guitar and accordion), Sven-Erik Magnusson (vocals, guitar, and clarinet). Later the band were joined first by Rune Bergman on bass guitar and then by Sven-Olof Petersson on tenor and baritone saxophone. The group made their first EP as a quartet in the early 1960s ("Let's Think About Living", "Guitar Boogie", and others).
https://en.wikipedia.org/wiki/Sven-Ingvars