Here is a brief history of Electronic Voice Phenomena (EVP), this is where sounds are found on electronic recording devices that are interpreted as voices of spirits and those sounds were not audible at the time of recording.
Psychologists believe EVP is a form of auditory pareidolia (interpreting random sounds as voices in one’s own language). Other rational explanations for EVP also include apophenia, equipment artefacts, and hoaxes
These are the 3 main people who are affiliated with EVP
Thomas Edison was born in Milan, Ohio, USA on 11th February 1847 and dies 18th October 1931.
He was an inventor(the phonograph, motion picture camera and the practical electric light bulb.)
In the 1920s Thomas Edison tried to invent a machine that would communicate with the dead.
“If our personality survives, then it is strictly logical or scientific to assume that it retains memory, intellect, other faculties, and knowledge that we acquire on this Earth. Therefore … if we can evolve an instrument so delicate as to be affected by our personality as it survives in the next life, such an instrument, when made available, ought to record something.”
Thomas Edison never succeeded with his invention but he did believe that it might be possible to capture disembodied voices with a machine.
Friedrich Jurgenson was born in Odessa in the Ukraine on 8th February 1903 and died 15thd October 1987.
He was recording bird songs and on playback he could hear voices including his mother’s voice saying in German, “Friedrich, you are being watched. Friedel, my little Friedel, can you hear me?”
He recorded of hundreds of such voices and would earn the title “the Father of EVP”.
In 1960 he received a voice message to use a radio as a transmission medium and he later fixed the frequencies to around 1445-1500 kHz with 1485 kHz now called the Jurgenson Frequency.
Friedrich Jurgenson published two books Voices from the Universe and Radio Contact with the Dead.
Konstantīns Raudive was born in Asūne, Vitebsk Governorate in Latvia on 30th April 1909 and died 2nd September 1974.
He studied parapsychology and was interested in the possibility of life after death.
Raudive read Friedrich Jurgenson’s book Voices from Space and was so impressed by it that he arranged to meet Jurgenson in 1965.
They then worked together to make some EVP recordings however their first efforts were not really successful although they they could hear very weak and muddled voices.
Konstantīns Raudive published a book on EVP called Breakthrough: An Amazing Experiment in Electronic Communication with the Dead in 1968 and republished into English in 1971 where described EVP as a typically brief word or short phrase.