Dahl came from a literary family; his father being the translator and provost Jákup Dahl.[2] His own poetry has been described as more modernistic than that of many previous Faroese poets.[3]
His family also contained musicians like his grandfather Georg Casper Hansen, and Dahl himself was noted as a composer. In youth he did not know how to transcribe his compositions so would work on them in his head before performing them at cultural events. As a composer he wrote musical settings for 34 Erik Axel Karlfeldt poems and created around 450 compositions in all.[4]
In the mid 1990s, Marianne Clausen made musical transcriptions of his many compositions, and published them as Atlantsløg and Atlantsløg II under his name.[5][6][7]