EVP, or Electronic Voice Phenomena, are sections of static noise on the radio or electronic recording which some listeners believe sound like voices speaking words, and which paranormal investigators interpret as the voices of ghosts or spirits. Recording EVP has become a technique of those who attempt to contact the souls of dead loved ones or during ghost hunting activities. In addition to deceased spirits, various paranormal investigators say that EVP could be produced by psychic echoes from the past, psychokinesis unconsciously produced by living people, and aliens. According to parapsychologist Konstantin Raudive, who popularized the idea, EVP are typically brief, usually the length of a word or short phrase.
Those who believe in the existence of EVP as a paranormal manifestation have a number of beliefs as to what EVP may possibly be. Common explanations include living humans imprinting thoughts directly on an electronic medium through psychokinesis and communication by discarnate entities such as spirits, nature energies, beings from other dimensions, or extraterrestrials.
As the Spiritualism religious movement became prominent in the 1840s–1920s with a distinguishing belief that the spirits of the dead can be contacted by mediums, new technologies of the era including photography were employed by spiritualists in an effort to demonstrate contact with a spirit worl. So popular were such ideas that Thomas Edison was asked in an interview with Scientific American to comment on the possibility of using his inventions to communicate with spirits. He replied that if the spirits were only capable of subtle influences, a sensitive recording device would provide a better chance of spirit communication than the table tipping and ouija boards mediums employed at the time. However, there is no indication that Edison ever designed or constructed a device for such a purpose. As sound recording became widespread, mediums explored using this technology to demonstrate communication with the dead as well. Despite the eventual decline of Spiritualism through the latter part of the 20th century, attempts to use portable recording devices and modern digital technologies to demonstrate life after death continued to be promoted in popular culture and by a cadre of dedicated believers.
In 1980, William O’Neil constructed an electronic audio device called The Spiricom. O’Neil claimed the device was built to specifications which he received psychically from George Mueller, a scientist who had died six years previously. At a Washington, DC, press conference on April 6, 1982, O’Neil stated that he was able to hold two-way conversations with spirits through the Spiricom device, and provided the design specifications to researchers for free. However, nobody is known to have replicated O’Neil’s results using their own Spiricom devices. O’Neil’s partner, retired industrialist George Meek, attributed O’Neil’s success, and the inability of others to replicate it, to O’Neil’s psychic abilities forming part of the loop that made the system work.
Since EVP has been ignored and derided as fiction by the scientific community and is not generally studied by academic researchers, there is no singular consensus on what all EVP are. However, there are a number of straightforward scientific explanations that can account for why some listeners to the static on audio devices may believe they hear voices, including radio interference and the tendency of the human brain to recognize patterns in random stimuli. A percentage of recordings may be hoaxes created by frauds or pranksters.
The very first EVP recordings may have originated from the use of tape recording equipment with poorly aligned erasure and recording heads, resulting in previous audio recordings not being completely erased. This could allow a small percentage of previous content to be superimposed or mixed into a new silent recording.
Interference, for example, is seen in certain EVP recordings, especially those recorded on devices which contain RLC circuitry. These cases represent radio signals of voices or other sounds from broadcast sources. Interference from CB Radio transmissions and wireless baby monitors, or anomalies generated though cross modulation from other electronic devices, are all documented phenomena. It is even possible for circuits to resonate without any internal power source by means of radio reception.
Capture errors are anomalies created by the method used to capture audio signals, such as noise generated through the over amplification of a signal at the point of recording.
Artifacts created during attempts to boost the clarity of an existing recording might explain some EVP. Methods include resampling, frequency isolation, and noise reduction or enhancement, which can cause recordings to take on qualities significantly different from those that were present in the original recording.
Portable digital voice recorders are currently the technology of choice for EVP investigators. Since these devices are very susceptible to Radio Frequency (RF) contamination, EVP enthusiasts sometimes try to record EVP in RF and sound screened rooms. Nevertheless, in order to record EVP there has to be noise in the audio circuits of the device used to produce the EVP. For this reason, those who attempt to record EVP often use two recorders that have differing quality audio circuitry and rely on noise heard from the poorer quality instrument to generate EVP.
A few German enthusiasts coined the term Instrumental TransCommunication (ITC) to refer more generally to communication through any sort of electronic device such as tape recorders, fax machines, television sets or computers between spirits or other discarnate entities and the living. One particularly famous claimed incidence of ITC occurred when the image of EVP enthusiast Friedrich Jurgenson, whose funeral was held that day, was said to have appeared on a television in the home of a colleague, which had been purposefully tuned to a vacant channel. ITC enthusiastists also investigate TV and video camera feedback transmission loops.
Some EVP enthusiasts describe hearing the words in EVP as an ability, much like learning a new language. Skeptics say that the claimed instances are all either hoaxes or misinterpretations of natural phenomena. Neither EVP nor ITC are researched within the scientific community and, as ideas, are generally derided by scientists when asked.
