Since the dawn of man, people have been trying to communicate with their lost loved ones, deceased friends, and important figures that have crossed-over. Shamans, mediums, and channelers have always been used historically in attempts to communicate with the dead. However with the birth of electricity, people have sought newer methods through science to talk with these discarnate spirits. Thus within the last one hundred years, EVP, otherwise known as electronic voice phenomenon, was born.

EVP is the receiving of a voice on audiotape from which there is no known source (Guiley 2000). This has been considered highly controversial subject in the paranormal field. Believers in the paranormal often associate the voices heard on these recordings to ghosts, spirits, or extra terrestrials. Skeptics claim they come from radio or television transmissions or imagined from white noise. Many EVP samples available were recorded by simple cassette recorders without being able to verify a strict methodology to avoid outside interference. With the constant possibility of audio contamination, EVP on its own can hardly be considered concrete evidence of a haunting. However, it continues to thrive with those conducting research and grow as better technology becomes available.

One of the first known attempts at EVP was that of Thomas Edison. He believed that an electrical device could be made to communicate with the dead. He stated in the October 1920 issue of Scientific American that he was working on such a device. However, nothing was ever completed.

Electronic voice phenomenon did not officially become discovered until the late 1950's when the Swedish opera singer, Friedrich Jürgenson, was recording bird songs in his garden. During the playback of his recording, a Norwegian voice interrupted his garden sounds by talking about nocturnal bird songs. Then, it discontinued and the garden sounds returned. Since he was out recording bird songs, he found it to be too coincidental that this strange voice was also talking on the subject. He could not accept this as a possible radio transmission and thus began taking more and more recordings. Some voices on playback even gave him instructions on how to record more voices (Shadowlands, 2004).

The second main contributer to this field of research was Dr. Konstantin Raudive who cataloged over 100,000 EVP messages he recorded. Many of these messages were polyglots, sentences composed of multiple languages. Raudive was often criticized for misinterpreting the voices (Poysden 2004). Many skeptics felt it was absurd that a spirit would comment on such mundane things as the color of Raudive's sweater. Others criticized the translations. Why would spirits who were fluent in multiple languages unable to speak in simple, proper, grammar? Regardless, he continued his work until death and was accredited for his book, Unhoerbares Wird Hoerbar (The Inaudible Becomes Audible).

Modern EVP can be performed with only a couple basic items, primarily a cassette recorder and an external mike. The external mike should have enough cord so that the turning of the cassette wheels is not recorded. Since the cassettes will be carefully reviewed and clear sound transfer is desirable, high quality tapes with a broad frequency range is recommended. Place the mike in a quiet location that is void of external noises such as traffic or running appliances.

World ITC, one of the leading research organizations in EVP, recommends using a mild white noise during recording of EVP (About.com, 2004). This may be a white noise generator or a radio tuned between stations. Skeptics however feel this simply introduces a better possibility that the listener experiences audio simulacra. Audio simulacrum is the brain's ability to take unrecognizable noise and process it as more familiar sound, such as a voice. Thus while ITC states it increases the amount of received discarnate voices, many researchers avoid it.

When starting the tape, clearly state the location and date. This helps you to identify the tapes later, especially during archiving. You may also wish to give a welcome to all spirits present at the time. Some researchers will then leave the tape to quietly record by itself. However, many researchers prefer a question and answer approach. They will all a series of direct questions such as “are there any spirits present?” and “what are your names?” out loud, leaving several seconds in between for a spirit to give its reply.

Interpretation of the results is more difficult. Generally, it involves reviewing all of the recording, often multiple times in order to determine if any unusual voices are present that were not heard during the original taping. With computer assistance from such programs as Adobe Audition, faint sounds can be boosted and static removed.

The question lies as to why these voices are not heard at the time of taping. Skeptics are quick to point out that it is most likely simulacra or people whispering off camera. However, Utah Ghost Hunter's Society and South Texas Ghost Hunters Alliance have a different opinion. They find most of their EVPs in the 0 - 300 Hz. range. The human voice only has a range of 300 to 3000 Hz. Thus, they cannot be made by someone living. In addition, a healthy human ear can only hear from 20 to 20000 Hz. Low frequency voices could normally go unnoticed or not heard at all.

The problem with searching for EVP at low frequency ranges, such as infrasound, is that humans do not normally listen intently in this region or they cannot hear this region at all. Thus, sounds associated with natural or mechanical items can be confused with EVP. Then again, maybe the voices are there of the deceased and we just need to listen harder.