Idaho Paranormal Society
EVP Theory
Electronic Voice Phenomenon or EVP for short is where voices and noises sometimes not heard by the human ear are recorded on various electronic devices such as audio cassette recorders, digital audio recorders, audio from video recorders and so on.

How these voices actually get onto the media for us to be able to play back when we did not hear it with our ears is still up for debate. TIPS has a theory that the energy given off by an object projecting itself in the form of a voice or noise communication my actually modulate the pickup sensor (dynamic mic, electret condenser microphone, etc) using low level magnetic or RF (radio frequency) energy.

Our ears are designed to pick up vibrations and differences in pressure which is then converted to an electrical stimulus in our cochlea and transmitted to our brains for interpretation. Our ears can hear roughly between 50 and 30,000 Hertz of frequency bandwidth. But that bandwidth consists of vibrations in the air. Did you also know that radio transmitters can also send out signals in the same frequency range? Government and other entities (pardon the pun) have been using VLF (Very Low Frequency) transmitters for decades. One application is for transmitting signals to submarines deep within the oceans where standard HF and VHF radio signals cannot penetrate.

Thinking about VLF radio signals, being magnetic in nature, is it not possible that a spirit or entity could give off magnetic frequencies similar to standard audible frequencies except they are RF instead? If that were the case, this magnetic energy would interact with the pickup sensor of a recording device in almost the same way as audible frequencies do with the exception of not being able to physically hear it without aid.

TIPS is currently seeking ways to test this theory. One such way is to use a coil of wire usually found on the diaphragm of a dynamic microphone attached to one recorder, while simultaneously recording on a similar recorder in close proximity. If its RF or magnetic energy then both recorders should theoretically hear the same thing, with the exception of the test recorder not hearing background noise. Another thought is to leave the coil inside the magnet on a dynamic microphone with the diaphragm material cut out to see if it is a difference of magnetic fields and not the sum that causes the audio to manifest.

TIPS is using several methods to record EVPs. We use Olympus WS-100 Digital Audio Recorders. In high quality mode (and you do not want to record in anything LESS than HQ) they will store about 4 and a half hours of audio. We place a recorder in each location of interest statically (we leave them there and don't move them). The reasons for having this many recorders going at the same time are first, to catch anything that might be in the area, secondly we want to see if audio heard in one area is also heard in another (this can validate outside noises so you can discount them), third, help determine the strength of the energy used to manifest an EVP (if an entity can be heard on one recorder it shows locality but if it can be heard on multiple recorders the strength of the energy used is indicated indirectly by proximity of recorders). Also beneficial is the fact that team members will be heard and observations recorded on the audio making note taking easier and with less errors.

In the hottest spots we use two recorders placed exactly 6 inches apart and started at the same time. The reason for this is simple. TIPS is trying to determine the general direction the EVP is coming from. Human ears are approximately 6 inches apart. We can determine on which side of our heads a sound is coming from by which ear hears the noise first and also the intensity of the sound. The same goes for audio recorders. The audio files will be channeled in the audio processing software so the right recorder plays on the right channel and the left on the left thus making it a stereo recording. In this configuration we hope to be able to hear if an EVP comes from one side of the room or the other. This may help in follow up investigations to help determine the best location to place the recorders next time, and also determine if the entity(ies) are mobile when making statements. I know this sounds trivial but its interesting data and sound scientific method.

EVP Protocol
When an investigation is over, or the digital audio recorder has run out of memory the data is transferred to the main TIPS laptop. These files are then distributed on USB memory sticks (dongles if you like) to other team members for both secondary review and backup (an ounce of prevention...).

Our Olympus WS-100 recorders have a feature where the battery jacket slides off revealing a USB port that allows us to plug them directly into the laptop and the files are accessed just like you would any file on a USB memory stick. No drivers, nor cradles, no cables, wonderful! Files are recorded in WMA format and sound great. Each 4 hours file is approximately 60 megs in size.

The audio files are loaded and screened with Adobe Audition. We have found that although this is an expensive software package, nothing on the market so far compares. An add on filtering package we use is call SoundSoap made by Bias software. Its a bit cheaper at $99 but well worth it.

Often over looked is the quality of headphones you use to listen with. Standard over the ear headphones DO NOT CUT IT. We have found that ear-bud type headphones that fit into the ear canal are best suited for listening to the subtleties of EVP work. A rich frequency response is also required. Cheap headphones have a limited ability to reproduce sound. Check the box for the response table and make sure you get the best response you can for your money. In addition to these headphones, covering your ears with hearing protection such as shooters hearing protection further provides for a lower ambient noise level. With two kids, a dog and an active household the more you can filter out the better. Noise canceling headphones are unacceptable. Due to the nature of their function, noise canceling headphones may interfere with the quality of audio and could cause you to miss something you would have otherwise not. Noise canceling headphones work by monitoring the noise outside of the earphones and then mixing the exact opposite wave form in with the audio coming from the device you are listening to in order to cancel the wave pattern of the undesired noise. This can cause distortion and cancellation of desired wave forms and you might not even be aware of it.

Processing Suspect EVPs
There are several things to be aware of before attempting to process an audio file for EVPs. I know some of this may sound like common sense but please bear with me.

First and foremost, it is very important to not edit the original file! Copy your originals and work with the copies. If you accidentally save changes to the original file, whoops! All gone. Its simple but easy to forget. All it takes is losing a valuable audio file and not be able to recover it to make you and the leaders of your group mad for a long time. Suppose an entity told you something ground-breaking but you never made a back up and you saved over the top of it? Best to not let Murphy in that door.

Concentration is important. When listening to hours upon hours of audio, and most of the time just white noise, one can be tempted to distract themselves by doing other things such as surf the web, read emails or play solitaire. When you do these things you are taking your attention away from the audio you are trying to listen to. And although you might think you are doing a good job, if you are reading to yourself you will be hearing your internal voice and not what's coming into your ear unless it is very obvious. In my experience, not many EVPs jump right out and grab your attention if you're not focused. Set aside the time to dedicate strictly to listening to the audio and leave the other stuff for later.

Food and snacks. Along with distractions, eating food or chewing gum can be equally destructive when listening for EVPs. The sound your mouth makes as you masticate travels into your ear faster than sound through the air. Its also impossible to ignore this noise since it travels through your mandible into your ear canal. Crunching and chewing makes noises that will cover up any subtle noises or phrases that you are desperately trying to find. In addition, loud crunching will desensitize your ears for a period of time due to the intensity of the sound and you may not be using your full audio faculties for a while thereafter. If you are hungry, pause the audio and eat, then resume when you are done. Common sense right?

Note taking. It is VERY important to create a log for every audio file that you process. There are many reasons for this. As you listen to your audio, note down the time it happened and a brief description. If you heard a voice that is unfamiliar to you, write down the time it occurs, what you think it says and any contextual information that might make deciphering the phrase easier. One reason for this is that you will have people wanting to validate your claim to an EVP or double up your efforts by reviewing your original audio file. If you can't tell them where EXACTLY in that file to find it you are wasting their time and yours. Your contextual information will also help locate the EVP by giving the reviewer references to other happenings that they can look for. Ever hear something cool and then get distracted before you had a chance to review it, only to realize you don't remember where in the file it was located? Take notes! Another reason to make notes and mark times is if you have multiple recorders going at a location. When reviewing other audio files you have a reference sheet by which you can locate noises heard by other recorders, EVPs that span the distance and also help determine if noises heard on the recorder(s) are external to the location such as cars, trains, loose shingles on a garage outside, etc. Please keep a log for each audio file you review and keep your logs for the duration you keep your evidence, hopefully forever.

When a possible EVP is located, note its time, then that section of audio is clipped out and copied to a new file. If the EVP does not need to be filtered because it is perfectly understandable, save the file using a standard convention that your entire evidence team uses. TIPS uses the following convention:

location_name date recorder_number file_number audio_timeline description.XXX

Example: petes 31106 R1 F1 3.04.21 'im dead jim'.wma

The location name is the location of the investigation. The date is an obvious one but we use dates without dashes and two digit year such as 31106 and so on. Our recorders are numbered so its best to note the number of the recorder next. Since each recorder can save multiple files, or have multiple files made by the same recorder it is necessary to specify which file you are on. The audio timeline is the exact time in the audio file the START of the EVP was noted such as 3.04.21 meaning 3hrs, 4 minutes and 21 seconds. The description can be what you think the voice says or perhaps a brief description of the sound. Its not critical exactly where you put this information when you create your file names, but you have to be consistent and all of your team members must follow the same naming convention or it simply will not work. Do it right and everyone will know right were to go to see first hand where the EVP was caught on the audio file.

If the audio needs to be filtered, filter the audio BEFORE amplifying it. If you amplify the audio before you filter you amplify the noise as well. After filtering, amplify the audio to a reasonable level so clients and yourself do not have to strain to hear it. If there is still noise in the audio feel free to filter some more but beware. The more you filter the more distorted your audio will become and the harder it will be for others to hear. Some noise is a good thing and you cannot expect to get rid of it all. Ever heard an EVP file from some group and it sounds like computer noises and never actually heard what they were talking about? That's called over filtering in our book. Filter the best you can without distorting the EVP and bring the level up to something you and your client, or your fans for that matter, can listen to without strain.

Last but not least, back up all of your data regularly. Its all digital so once its gone, there is no getting it back.

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