[2] Together with the fiddler Ola Opheim, he was one of the most important Norwegian folk musicians in the decades after the Second World War.
[1][2] In addition to Nygaard himself on accordion, the quartet consisted of Ola Opheim on fiddle, Finn Westbye on guitar, and Håkon Nilsen on bass.
[2] The quartet won the 1973 Spellemannprisen contest in the category of folk music and old-fashioned dance, which was awarded for the first time that year.
He collaborated with musicians such as Oscar Skau, Sven Nyhus, Rolf Syversen, and Børt Erik Thoresen, and with the skier Ole Ellefsæter.
In 1995, the record company EMI released the catalog album Spelemannsliv (A Musician's Life) with selections from Nygaard's career.