Doug Ingle

Douglas Lloyd Ingle was an American musician, best known as the founder, organist, primary composer and lead vocalist for the band Iron Butterfly. He wrote the band’s hit song “In-A-Gadda-Da-Vida”, which was first released in 1968, and was the last surviving member of the band’s 1967–1969 lineup.

Biography summary from English Wikipedia, photograph via Wikimedia Commons.