What is EVP - Electronic Voice Phenomena?

We dig into EVP with some history and explanation to get you started...

When Was EVP Discovered?
EVP or "electronic voice phenomena" (electronic voice phenomenon) was discovered in 1959 by Swedish film producer Friedrich Juergenson, though, Thomas Edison was said to have theorized about EVP in the 1920s.  Other men in the 1930's, 40's and 50's reported some voice phenomena, but Freidrich has been considered the "Father of EVP" after recording hundreds of voices.
What is Electonic Voice Phenomena?
EVP is the practice of playing back audio recordings to listen for human voices, that were not heard audibly during the recording session. Sometimes amplification and noise filtering is required to hear the voices. Some EVP is more easily heard and than others. EVPs have been recorded of men, women, and children of varying ages, different languages, tones and emotions. EVP are typically words, and short phrases.  Sometimes EVP may just be laughter, screams, groans, and other vocal noises.
What to Expect with EVP Sessions
Most ghost hunters will ask questions during an EVP recording session. The ghost investigator should remain silent between questions, allowing ample time for answers and so as to not "pollute" the recording with his or her own sounds or words. Upon playback of the recording, the ghost hunter listens intently for any EVP that may have been picked up by the recorder.  Sometimes, the sounds recorded during the silent time between questions is strange or unintelligible; but when slowed down in EVP editing software, a word or message can be discerned.  
Some EVP messages that have been recorded are startling.  EVPs, especially when a ghost responds accurately to questions that correlate to the haunted location or even the questioner, can be startling.  Personal information about people in the room, during EVP communications, may be given, from time to time, by ghosts or spirits.
No doubt, the biggest room for EVP error is noise created by the ghost hunters themselves. Brushing up against a wall, shuffling of feet, recorder motor noise, background noise, and simply speaking during the recording session are the most common forms of mistakes by EVP investigators. Perhaps, then, the best audio recorder would be one with an external microphone that can be placed away from the recording machine and ghost hunter. Hand-held audio recorders only invite more error than the capture of authentic EVP.  Also, digital audio recorders produce less noise (if any), and are easier to transfer to the computer for use in EVP editing software. The EVP recording device should be sat down and moved away from, and in a location that has been deemed free from background noise, but high in ghostly activity. Ask questions from a distance while remaining still, and wait 20-30 seconds for a ghostly response.

EVP Analysis & Examples
After the ghost hunt, slowly and carefully analyze the recording using audio editing software - Audacity is offered free on the web, as example.  Many ghost hunters try and hear something that is just not there on the recording. Listen for clear, unmistakable words but do not be afraid to analyze any and all strange sounds to see if words can be brought out of the noise or "hiss."  
Listen to Examples of EVP Voice Recordings:
Ghost EVP
Electronic Voice Phenomenon
EVP Recordings