Ghost Hunting 101

EVP - and sound explained

EVP stands for Electronic Voice Phenomenon; voices caught on recording devices such as tape recorders. Thomas Edison first introduced this concept to the world during the latter part of his life. He became obsessed with the afterlife and began trying to prove that we do go on when our bodies die. In the few weeks prior to his death, he kept himself locked in a room with a modified version of the phonograph he invented earlier in his life. He would turn this machine on, and while alone, begin asking questions. It would record his questions as well as the pauses in between. When playing the recording back on a regular phonograph, he was amazed to find other voices providing answers. Since no one else was in the room during the experiment, he deducted \par that these were "spirit voices" . The recording device he used is currently on display at the Smithsonian Institute. Using the same concept, we place tape recorders, DAT (Digital Audio Tape) recorders, etc., in "active" areas and find strange voices recorded. Often times, people talking about us and questioning what we are doing with all this strange equipment.

EVP has always been and still remains one of the more controversial methods of trying to provide evidence of the paranormal. The basic principle behind EVP collection is the use of an audio recording device in an attempt to catch voices and/or sounds of an unexplained nature. Before we begin to analyze sounds we need to gain a greater understanding of how they operate and the physics be hind their creation.

Sounds are changes in pressure in an elastic medium such as the atmosphere that can be detected by the human auditory system. This pressure change is called a sound wave. The human auditory system can only interpret these changes in pressure or sound waves if they are cycling in the range of 20 to 20,000Hz. Anything below the 20Hz level is called infrasonic and anything above 20,000Hz is called ultrasonic. The human ear cannot perceive sound waves in the infrasonic or ultrasonic sound range. A sound wave will also loose intensity the farther away from the source of the atmospheric disturbance it travels. A sound wave can also travel through solid objects such as walls. This makes it difficult to determine the originating source of the sound wave.

Frequency is the measure of the rate at which electromagnetic waves are generated. Frequency is measured in cycles per second, called hertz (Hz) after the German scientist who first discovered radio waves. (1 Hz equals one cycle per second.) The field around power lines, for example, is predominantly 60 Hz. Radio wave frequencies range from 300 Hz to billions of hertz. Electromagnetic waves with similar frequencies can be grouped together. These groupings form the electromagnetic spectrum with low-frequency waves (sometimes called ELF for "extremely low frequencies") at one end and high-frequency waves at the other. Radio waves, microwaves, and infrared light can be found at the lower end of the spectrum. Ultraviolet light, X-rays, and gamma rays occupy the upper end. Visible light, including sunlight, occupies the middle region. Microwaves are used in the transmission of telephone and telegraph messages, communications between earth and orbiting satellites, and in relaying certain television broadcast signals.

Based on what we know in regards to the physics of sound, most people will accept that the human voice is generally incapable of speaking below the 280hz mark. Extremely low frequencies (30 to 300Hertz) are the range most EVP is captured, and according to the laws of physics, impossible for the human voice to cycle at. When you capture a potential EVP you must first analyze the voices through spectral analysis to prove it is in fact in the ELF range of the sound spectrum. Once you validate the voices in question are in the ELF range, you have a legitimate EVP. These anomalies seem to be limited to locations with purported activity thusly linking them with ghostly phenomena.

There are a number of computer software programs on the market that will detect and log the spectral range of a recorded or live sound wave. The most widely used is a program called Cool Edit Pro. When looking for software to analyze your EVP you want to make sure it has a built in Spectrogram. The Spectrogram is the portion of the sound program that will show you the spectral range or Hz level the sound cycles at. Most of these spectrogram programs will give a visual representation of the spectral graph chart along with the Hz level of each spectral region.

When importing a sound from an external recording device, you want to pick up an adapter from Radio Shack or any other electronics store of your choice. This adapter will plug into the headphone or audio output portion of your recording device and plug into the MIC or audio input of your sound card. Once you have your recording device connected to your computer you want to launch the spectrogram portion of your software and press play on the recording device you are using. This will immediately begin to read the Hz level of the sounds you have recorded. When you reach the portion of your recording with the suspected EVP you can view the spectrogram and validate its Hz level. Some of these programs will save the files to your hard drive in electronic format. If your software has the capability, it is easy to isolate and convert that portion to MP3 or WAV format for posting to your website. This is how we capture, analyze, and validate these anomalous voices that defy rational, logical, and physical explanation


Sound Waves

Measuring terms:

1,000,000 cycles per second = Megahertz (MHz)

1,000 cycles per second = Kilohertz (KHz)

1 cycle per second = Hertz (Hz)

These frequency numbers are in Hertz, which is cycles per second:

1 Approx. beginning of brain waves

>6.66 Theta brain waves

7.85 Alpha brain waves

15.7 Beta brain waves

30-30.56 Government VLF stations

32-33 Government VLF stations

34-42 Government VLF stations

50 Approx. Upper limits of brain wave frequencies

60 Produces an audible sound

ELF - Extremely Low Frequencies (30 to 300 Hertz):

A great deal of attention is paid by the scientific and experimenter communities to the frequencies below 9 kHz. Here you can monitor, and actually hear, a wide range of "natural radio" phenomena. Events such as "whistlers", which are believed to be the sound of the energy pulse of a lightning bolt following the earth's magnetic field, can be heard with special radio receivers. These radios (which are surprisingly easy to build) are capable of tuning down to 300 cycles and below, where these signals are heard. There are many other sounds from known and unknown sources that are being investigated as well. Many who assist the scientific communities in such studies do not even listen to the sounds produced, but monitor such things as the changes to background noise using pen traces on paper tape, or computer sampling of variations in measured voltages. Through this activity, further knowledge is being developed about the radio propagation in this region, which still contains many mysteries.


FREQUENCY is a measure of the rate at which electromagnetic waves are generated. Frequency is measured in cycles per second, called hertz (Hz) after the German scientist who first discovered radio waves. (1 Hz equals one cycle per second.) The field around power lines, for example, is predominantly 60 Hz. Radio wave frequencies range from 300 Hz to billions of hertz. Electromagnetic waves with similar frequencies can be grouped together. These groupings form the ELECTROMAGNETIC SPECTRUM, with low-frequency waves (sometimes called ELF for "extremely low frequencies") at one end and high-frequency waves at the other. Radio waves, microwaves, and infrared light can be found at the lower end of the spectrum. Ultraviolet light, X-rays, and gamma rays occupy the upper end. Visible light, including sunlight, occupies the middle region. Microwaves are used in the transmission of telephone and telegraph messages, in communications between earth and orbiting satellites, and in relaying certain television broadcast signals.


ELF/VLF radio waves penetrate deeply beneath the surface of the earth and interact with the geologic structure of the earth. This interaction induces secondary fields with measurable effect upon and above the surface of the earth. Proper understanding of the physics of the generation and propagation of ELF/VLF waves and their interactions with earth materials will allow these waves to be used for applications such as sub-surface communications and exploration of the subsurface geological structure. From

Electromagnetic radiation with a high frequency carrier wave (e.g., radio wave) and an extremely low frequency (ELF) modulation is considered amplitude modulated (e.g. TDMA mobile phone systems). The modulation can also be pulsed where the carrier wave is switched on and off very rapidly in the rate of about 100 pulses per second (e.g., GSM mobile phone systems), while continuous wave (CW) radiation is generated essentially at a single frequency (e.g., analog mobile phone systems).


Natural ELF/VLF Radio - also called "Natural Radio" - is audio-frequency radio signals of Earth in the approximately 200 Hz to beyond 10,000 Hz (10 kHz) spectrum which are not man-made but occur naturally. Most of the best phenomena are heard between 400 Hz and 5 kHz. Interest in naturally-occurring ELF/VLF radio phenomena such as "whistlers" and "chorus" has enjoyed a rapid resurgence during the past 10 years on the part of academic research via orbiting space-probes and ground-based monitoring efforts, and also notably amongst amateur hobbyists world-wide, thanks to easy availability of sensitive receiving equipment. From

You can listen to some of the Natural ELF Radio sounds with streaming audio (Real Audio) courtesy of NASA.

More at

Sferics - Mainly the ubiquitous snap, crackle and pop of lightning all over the earth, this can be heard anytime, anywhere, on frequencies from 1 Hz to beyond 100 MHz. Just tune your AM radio to an empty frequency. Sferics below deserves special mention.

Listen to sample

More at

The ELF frequency range is critically important to the Navy because of its value in providing a way to communicate with submerged submarines. As a result of the high electrical conductivity of sea water, signals attenuate (or decrease) rapidly as they propagate downward through it. In effect, the seawater "hides" the submarine from detection while simultaneously preventing it from communicating with the outside world through normal radio transmissions.

We record wideband ELF/VLF (~200 Hz to 20 kHz) data at Palmer Station, Antarctica. Extremely Low Frequency (ELF, 30-3000 Hz) and Very Low Frequency (VLF, 3-30 kHz) are frequency bands to denote where the signals we measure are in the electromagnetic spectrum. Our signals happen to be in the audio range, so that if they were sound waves, you could hear them.


The degree to which a signal is attenuated depends on its frequency, however. The lower the frequency, the more deeply a signal can be received in seawater. In order to receive conventional radio

transmissions a submarine must travel at slow speeds and be near the surface of the water. Both of these situations make a submarine more susceptible to enemy detection. More about the Navy's ELF system:

FCC rules allow unlicensed stations to operate between 160 to 190 kHz providing that:

1.The power input to the final amplifier does not exceed one watt.

2.All emissions below 160 kHz or above 190 kHz are suppressed by 20 dB.

3.The total length of the transmission lines plus the antenna does not exceed 50 feet.


HAARP is a project funded by the US Senate and operated by the US Navy & Air Force. HAARP or "High Frequency Active Auroral Research Program," was supposedly started to communicate with submarines deep in the ocean using ELF radio waves, which can penetrate the ocean as well as the earths surface. With the power HAARP has it can focus all its radio waves into a single beam in the sky, which effectively exceeds its 3.6 million-watt power status. Still, to get a better idea, its 72,000 times more powerful than the US's most powerful radio station. With this much power the possibilities for use are endless; of course activists, conspiracy theorists, and environmentalists all have their own ideas for applications of this weapon / utility, both good and bad.


"Natural Radio" describes naturally occurring electromagnetic (radio) signals emanating from lightning storms, aurora (The Northern and Southern Lights), and most importantly, the Earth's magnetic-field (The Magnetosphere). This is a presentation of Earth's natural radio emissions that occur in the extremely low frequency to very-low-frequency (ELF-VLF) radio spectrum--specifically, at AUDIO

frequencies between approximately 100 to 10,000 cycles-per second (0.1 - 10 kHz). Unlike sound waves, which are vibrations of air molecules that our ears are sensitive to, natural radio waves are vibrations of

electric and magnetic energy (electromagnetic waves) which-though occurring at the same frequencies as sound--cannot be listened to without an audio-frequency ELF-VLF radio receiver to convert the natural radio signals directly into the same sound frequencies. Another amazing realm of nature is thus ready to be explored and observed.



It has been theory for a number of years that "ghostly" manifestations cause a disruption in the ambient electromagnetic fields of a location. Due to this theory, investigators have incorporated a wide array of EMF (electromagnetic field) meters as part of their standard equipment. We have proven, based on this previous theory, that areas which appear to be "haunted" do in fact have erratic EM fields. The EMF meter has become the most basic and essential device of an investigators ghost hunting arsenal.

There are a wide variety of meters available on the market, ranging in cost from 10 dollars to 600 dollars. They are classified as single axis, double axis, and even triple axis meters. Here is a quick break down of the various meters on the market today.

Single Axis EMF meters read from one direction, usually directly in front of them. These units with have 1 sensor housed in the case. This means you have to be pointing directly at what you are trying to get a reading of in order to register a hit. If you are using a single axis meter on an investigation, an anomaly could be 2 inches above the meter and you would never get a reading, if the field were small. However, by turning the meter 90 degrees and facing the sensor towards an energy field it will take an accurate reading. Additionally, the sensors could either be to the sides or the bottom of the meter, and you would not register a correct reading unless the orientation was changed. All EMF meters have to be in the EM field of an anomaly before they will register a reading. The more sensitive the meter, the further away from the anomaly you can be before registering a reading.

Double or Dual Axis EMF meters take readings from 2 directions, due to the fact that they have 2 sensors, usually directly in front of the unit and on the bottom. Again, this will vary from model to model. Like the single axis, if this reads from front and bottom and an anomaly is directly above the meter, it will not register the actual field strength unless the orientation of the meter is changed.

A Triple Axis EMF meter will read from 3 directions, usually from front, bottom, and top. Again, this also will vary from model to model due to the position of sensors within the unit. Like the others, if the anomaly is to the sides where there are no sensors, you will not register any deviations unless the orientation of the unit is changed.

Now we get to the drawbacks of these meters. All meters have a range of exactly zero feet. This means that all gauss meters, electric field meters, RF/microwave meters, etc. can only measure the strength of the field AT THE LOCATION OF THE METER. What distinguishes one meter from another is the sensitivity. In other words, what is the smallest field strength that the meter can detect? A gauss meter with sensitivity of 0.1 mG is more sensitive than a meter that can only detect down to 1.3 mG. While the meter that is more sensitive can be successfully used further away from the source of the field, it is still only measuring the field at the location of the meter. The closer to the "core" of the anomaly your meter is, the stronger the field reading, as the field strength dissipates rapidly from its generating source.

Another factor we have to take into consideration with this research is if the meter is a calibrated or non-calibrated meter. A non-calibrated meter reads alternating fields, which means it can read energy at varying Hz rates. A calibrated meter is designed to read direct currents and is usually calibrated to read energy cycling at 50 or 60Hz, because this is the Hz rating of the power grid in the US. We do not know exactly what the variation of Hz levels these anomalies cycle at yet. A lot of times when using a calibrated meter that is set for 50 or 60Hz, you will not get a reading on an anomaly if it is cycling at, say, 30Hz.

It is best to use both calibrated and non-calibrated meters in your research. If you are using a non-calibrated meter and you receive an energy spike, you can quickly try to get a reading with the calibrated meter. This will determine immediately if it is a man-made field. If the meter which is calibrated at the 50 or 60Hz level gets a reading, it may be a man-made field. If you are not getting any readings with a calibrated meter, but the non calibrated meter is spiking then you have a strong case for an anomalous energy field, since it is not cycling at 50 or 60Hz as most man-made fields do.

For a good starter meter I would recommend the "Dr. Gauss" Gauss meter. It can be purchased at, just click on the Store. They are also the cheapest place to purchase equipment. Dr. Gauss is a single axis meter with a moderate sensitivity level, but it gives an audible alert which is extremely handy in dark places.

Anything cycling at 50 or 60Hz can be a man-made energy field, or it could also be paranormal in nature. When in doubt use an Electrostatic Meter, Thermal Probe, Geiger Counter and so forth to determine if what you are reading can be captured on these other tools.

Trifield Natural EMF Meter

The Natural meter was originally designed to pick up Geometric Storms. If you use this meter after a solar flare, there will be a lot of disturbances in the upper atmosphere, which can cause it to give false readings. Also, this meter is so sensitive it can pick up people walking in a different room, which will cause it to go off. It is designed to block out man made EM fields so it ignores energy that cycles at 50-60Hz. The problem with this in our line of work is that a lot of times anomalies will cycle at 50-60Hz and by using this meter you will never get a reading when they cycle at that level. This meter has also been known to detect thunderstorms several miles away, so to be on the safe side you have to know the weather conditions for a 50 mile radius from where you are conducting your investigations.

This meter does have an adjustment to lower the sensitivity level, so that it will not detect your energy field. The problem with this is that everybody produces a different level of EMF, therefore it may not go off while you walk next to it, but it will when someone else does.

Electrostatic Field Meter

We have noticed during our investigations these "anomalies" carry a large static charge. This is part of the atmospheric disturbances we detect during a manifestation. A electrostatic field meter is designed to pick up on high static charges in a location. Many people report the hairs on the arms standing up when they witness a manifestation. This could be from the amount of static electricity these anomalies produce.


Intelligent Haunting - Exhibits intelligence, interacts etc. Most fun and hazardous. These little guys have been known to bite, hit, shove, kick, and throw objects at the heads of investigators. A few years back one investigator stuck his head up in an attic where an intelligent "entity" was present, and suddenly had a piece of wire wrapped around his neck choking him. I suggest putting the camcorders in these "alien" locations before sticking your head in there. This way you can see what is up there.

Residual Haunting - A "recording of time" that keeps playing itself over and over. Some speculate that it's residual "psychic" impressions left on the land or building due to extreme emotional stress.

Poltergeist - This is usually activity conducted by a human agent, oftentimes that of a pubescent child thought to be creating a PK Burst or PSI activity. Upon MRI scans there is a increase in Theta brain wave activity and the Pineal Gland seem to be overly active.