Loudspeaker put on the roof [edit] According to Dan Aykroyd, the horn-shaped loudspeaker atop the Bluesmobile was a replica of a gigantic Cold War-era air raid siren (CLM Model 92729DP) located in the playground of "Our Lady of Annunciation" in Ottawa, Canada, where Aykroyd attended elementary school. [7] The siren was made by a Canadian firm named CLM Industries, and Aykroyd asked that the same CLM model be used in the film to simulate the loudspeaker mounted on the top of the Bluesmobile and utilized as a public address system. [8]
