Scientists at the Lawrence Berkeley National Laboratory have begun work using a digital scanning apparatus that they hope will be able to reproduce sound from the only known audio recording of the assassination of President John F. Kennedy on Nov. 22, 1963, in Dallas.
Accordinng to Audio Technology Update, the recording was made through an open microphone on a police motorcycle during Kennedy's motorcade into Dealey Plaza, where the president was shot. The sounds were captured onto a Dictaphone belt at police headquarters, but scientific analyses of them over decades proved inconclusive, leaving unresolved whether three of four shots were fired that day.
Repeated analysis using mechanical means is wearing out the Dictaphone belt to the point of unusability. Leslie C. Waffen, an archivist with the National Archives, suggested that digital analysis could both map the sounds and remove extraneous noise like static and distant voices to reveal gun shots. After a June meeting of the National Archives Advisory Committee on Preservation, the job was left to Carl Haber and Vitaliy Fadeyev of the Berkeley laboratory, who have used a digital optical camera to replicate sounds on fragile Edison cylinders and long-play records. The process involves scanning the grooves of the Dictaphone belt electronically to create a digital image of the sound patterns.