Dating back to the 19th century, occultists, engineers, and hoaxers have employed new audio technology to communicate beyond the grave. This includes wax cylinders, white noise generators, AM radios, hacked phonographs, and other curious contraptions. Even Thomas Edison got in on the phone, making a machine to communicate with the spirit world. He later admitted it was a joke but, of course, his phonograph does enable anyone to hear from those who have passed on (and left a recording behind). Over at the Daily Grail, John Reppion surveys the history of "Ghost Boxes and Psycho-Phones":
In 1957 a Swedish painter by the name of Friedrich Jürgenson – a man so famed for his artistic ability that Pope Pius XII had a total of four portraits painted by him at his personal request – purchased a reel to reel tape recorder. Jürgenson only wished to record his own voice singing but, listening back to the tapes, he began to notice strange fadings in and out. In 1959 he and his wife went to spend the summer at a cottage they owned in the countryside, and Jürgenson took his tape recorder along. The machine had been left running outdoors to record the bird song, but on listening back hardly any birds could be heard. What sounded like a thunderstorm of static was, shockingly, interrupted by a loud trumpet and then a voice speaking in Norwegian. Friedrich was amazed to realise that it was the voice of his own long-dead father, seemingly speaking directly to him through the machine. Soon after his deceased mother’s voice also appeared on tape, and this was enough to convince Jürgenson to give up painting and devote the rest of his life to spirit recordings. Electronic Voice Phenomenon (EVP) is the name now commonly given to recordings which are believed to contain communications from ghosts, extraterrestrials, or other entities.