Electronic Voice Phenomenon

EVP is an acronym for Electronic Voice Phenomenon. Electronic Voice Phenomenon (EVP) is a term used to describe unexplained sounds or voices that are sometimes found on a recording media. Many researchers believe it is a voice of a spirit. Often times ghost hunts will involve unusual sounds, for example whispering or voice sounds. These sounds heard without a recording device is considered to be a disembodied sound. But EVP's sounds can only be heard later when listening to the recorded message from some kind of recording device. Giving an EVP it's classification of being an unexplained phenomena. 

Many researchers believe that the voices of the dead can be recorded and played back on a Digital Voice Recorder. And even possibly believing it is a way to communicate with the spirit world. Many paranormal researchers believe that the spirit world operates at a higher frequency because of the faster rate in which the paranormal messages occur. So spirit voice messages often demonstrate a shift in frequency outside of the normal human voice, frequency range. 
A human voice usually ranges between 300 Hz and 1000 Hz. Spirit EVP voices have been measured to 1400 Hz. As humans we live in a dense 3D world so it is believed that the spirit world is much less dense. Spirit voices often sound like regular speech only at a faster pace because spirit's are in a lighter bodily form. 

Not all EVP's are the same in message characteristics. Often times the messages will have a popping or snapping sound just before or after the EVP. Some researchers feel that the sound is a spirit attempting to connect or disconnect to the recording device. So the Properties of EVP's are not all the same researchers have classified them into classes Class A, B or C. Many times the messages are found by listening to the reverse direction of a sound track. The message length from spirits are typically very short in length, ranging from one word to short sentences. 

EVP researchers agree that the voices can be recorded anywhere or at any time. Many investigating the phenomenon claim that spirit voices can be transferred to a recording device no matter where the device is located or placed. So researchers who take audio recorders, video recorders, or use the open microphone method on investigations hope to capture an EVP must keep in mind that capturing an EVP is fairly easy. But, gathering proof of the afterlife takes solid evidence. To convince anyone that a true paranormal event has taken place some issues should be avoided that can occur when recording spirit voices. 
Tips on recording EVP's.
Electronic Voice Phenomenon (EVP) is a term used to describe unexplained sounds or voices that are sometimes found on a recording media. Many researcher's believe it is a voice of a spirit. Some researchers believe that the voices of the dead can be recorded and played back Digital Voice Recorder (DVR). Some even believe it is a way to communcate with the spirit world. Many EVP's will have a popping or snapping sound just before or after the EVP. Researchers feel that the sound is a spirit attempting to connect or disconnect to the recording device. 
Property of EVP's:
Are all EVP's the same in message characteristics?
EVP messages have been classified as Class A, B or C: 
Class A: easily heard and understood from the speakers of a sound system 
Class B: can be heard over the speaker but there may not be agreement as to the message. Some words may be agreed on. 
Class C: can only be heard with headphones and difficult to understand. 

Often times messages are found by listening to the reverse direction of a sound track. So the spirits words are clearly heard as if played in the correct direction and may disclose hidden messages. Some popular explanations for the existence of reverse messages are: 

1. Spirits experience a different time frame from us
2. Sometimes a EVP recording is done in a sound-rich environment. 
Are all EVP's the same in message duration?
EVP message length is typically very short, ranging from one word to short sentences. Several experimenters have found that messages will usually be less than two seconds in duration. And the words may be spoken very quickly. Popular theories for why this is so are: 

1. Quantum physics aspects suggests that there may be a limit to the amount of EVP information that can be transmitted. 
2. The energy required for a transmission of a spirits message is limited by available physical energy such as; that provided by sound, electricity or light. 
3. The experimenter's particular mediumistic capability is a restricting factor for message duration. 

Often EVP messages are preceded by a clicking or a popping sound. A physical world analog to this sound is the sound that was heard on old Citizen Band radio sets. When the send key was pressed, there was a brief burst of static before the voice was heard. 
Most messages are in the language of the experimenter, but some individual experimenters have received other languages. For instance, an English and German message has been received in a single session 
Why do most EVP's have a high frequency sound?
Humans live in a dense 3D world but it is believed that the spirit world is less dense. Spirit voices sound like speech at a faster pace because they are in a lighter spirit form. One explanation of this could be that the spirit world operates at a higher frequency. Many paranormal researchers believe that the spirit world operates at a higher frequency because of the faster rate in which the paranormal messages occur. So spirit voices often demonstrate a shift in frequency outside of the normal human voice, frequency range. A human voice usually ranges between 300 Hz and 1000 Hz. Spirit EVP voices have been measured to 1400 Hz. 
Paranormal researchers who take audio recorders or video recorders on investigations in hopes to capture an EVP must keep in mind that capturing an EVP is fairly easy. Gathering proof of an afterlife takes concrete solid evidence, making evidence the difference between science and myth making. In order to convince skeptics that a true paranormal event has taken place some issues should be avoided that can occur when recording spirit voices. 
EVP's are considered to be spirit voices by many paranormal researchers. However, they are still classified as unexplained phenomena. Most haunted locations involve unusual sounds, for example a whispering voice. For it to be labels EVP these sounds must be heard later when listening to the recorded message and not heard at the time of the recording. Otherwise these sounds would be considered a disembodied voice. Right before that recorded message, or EVP, is captured some investigators claim there is a clicking sound. These researchers feel that the spirit or spirits could be tuning into the microphone in order to leave the message. 
EVP researchers agree that the voices can be recorded anywhere or at any time. Many investigating the phenomenon claim that spirit voices can be transferred to a recording device no matter where the device is located or placed. Some experimenters have even placed recording devices in locked boxes or buried them in the ground and they still have captured an EVP. Various researchers state that a microphone is not even necessary. 
Traditionally ghost hunters and paranormal investigators usually seek out quiet locations for recordings so they can address questions aloud to any ghosts who might be present. However, more recently researchers recording EVP’s deliberately include high levels of simulated background noise to record the phenomenon. This simulated noise is known as white noise which they believe assists with the production of a paranormal voice. White noise could be running water or a radio not tuned to any particular station. This also provides an audio context and reassures the listener that the recording has not been manipulated. The key difference between these two types of EVP research is that in the traditional EVP research all efforts are made to exclude the possibility of any natural voices. And the new idea is to include sounds to help assist the spirit voices. 
When recording outside many different things can affect the microphone. Wind produces loud sounds so it carries a voice further and drowns out other sounds. To prevent this problem, microphones with special wind screens can be purchased. Ambient background sounds can also occur and are likely to be higher outdoors. In particular, real voices might appear on recordings made outside. 
One problem with audio recording of paranormal material is that it can be difficult to recall all possible natural sources of all the sounds present. It’s important to document any sound that’s heard to rule out it as paranormal. Even using a video recorder can produce the same problem; for example an odd sound that appears could be from out of the range of the camera. With a video camera present capturing a spirit voice on a recording is much more difficult to debunk. Similarly, locking a room off with just an audio recorder in it is also much harder to debunk. Both those ways for catching EVP's inevitably remain unexplained and hence spirit voices are captured. 
Debunking any possible EVP's is a very important step to verify that it is a true paranormal sound. Occasionally, recorded sounds could be coming from outside the building where the recording took place. These appear to be coming from inside the building; so when listening to the recording special consideration to background noises is necessary. If the background noise appears to fade drastically when a real loud sound is picked up, this could mean that your recorder has an auto-gain circuit (AGC). An AGC’s job is to keep sound levels roughly constant. Also, record details such as where, when, and how the recording was made; as well as the type of equipment used. All of this will help separate true paranormal sounds to non-paranormal sounds. 
Humans live in a dense 3D world but it is believed that the spirit world is less dense. spirit voices sound like speech at a faster pace because they are in a lighter spirit form. One explanation of this could be that the spirit world operates at a higher frequency. Many paranormal researchers believe that the spirit world operates at a higher frequency because of the faster rate in which the paranormal messages occur. For this reason some researchers occasionally edit recordings to slow them down. They do this to understand what they feel is the true meaning or message of what the spirit voice said. 
Editing or enhancing recordings can be helpful to understand the spirit voices. But, to be a good and thorough investigator, researcher or ghost hunter the original recording always needs to be kept. The most obvious way to analyze a sound recording is to listen to it. Once a sound recording contains apparent spirits voices or paranormal sounds make copies of it and keep it safe; it could become very valuable evidence. Also, cutting out a section of the recording to show the suspected paranormal sound to researchers is also helpful. It is recommended to leave a few seconds before and after the paranormal event. These seconds are important to establish context of the suspected paranormal sound. 
If using audio editing software on paranormal recordings do not apply more than one or two enhancements per sample. Also, apply exactly the same enhancements to all the recordings. If different types of enhancements are applied to each recording then they can not be objectively compared to each other. In some noise reduction processes an area of the recording must be nominated as noise so that it can then be removed from the sample which is interesting. Most audio editing software is designed to edit and enhance sound clips with a reasonable signal to noise ratio. It’s not recommended changing the audio format into a MP3 or WMA, these formats compresses, the file and it will not sound identical to the original recording. Do use uncompressed digital formats, like WAV, for editing and storing paranormal sounds. If WAV format is not used, skeptics will null and void your evidence 
To help decipher if where a sound or voice is of a paranormal nature you will need to go back to site of the recording, in order to examine the area more carefully. Otherwise it is difficult to judge what caused a particular possible paranormal noise. Try to recreate the suspected sounds by moving objects around or tapping them. This does not necessarily imply that the objects were moved by any paranormal means. To obtain good evidence of phenomena like this a video recorder could be used in conjunction with an audio recorder. With this method, it's much easier to rule out a non-paranormal sound.