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FAQ Frequently Asked Questions Equipment & Software for Recording EVP/ITC
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Question: What is the best kind of recording device for EVP?
Answer: The answer to this question has changed as technology has evolved. Today, digital voice recorders are recommended for experimenting in both field and controlled conditions. Other audio recorders, such as the cassette and reel-to-reel tape recorders, are excellent; however the mini-cassette or CD recorders have not been well received by the EVP community. Research has shown that the voice in transform EVP is formed by changing available audio-frequency sound into the voice. For this reason, we have found that it is sometimes necessary to provide background sound during EVP experiments when using a very quiet recorder. This is usually accomplished with an external microphone and such sound sources as a fan, static from a radio or running water. The sound of garbed foreign language voices is used by some people and a sample file of this can be downloaded from here. The objective is to provide sound with human voice frequencies that has many harmonics and overtones. "live" sound is preferred over computer generated sound, but "live voice" should be avoided unless it has been treated, such as in the crowd babble offered here. Digital voice recorders produce relatively more internal noise and work well in field conditions without the addition of background noise. However, they are not convenient for reviewing the resulting sound files, thus the need for a computer for review and possible filtering and amplification. In truth, it is fast becoming the norm for practitioners to us a computer for all sound file review.
Comment on the Panasonic RR-DR60 IC Recorder:
We have discussed the Panasonic RR-DR60 IC Recorder
on this website and in our book,
There is
No Death and There are No Dead. At one
time, the DR60 was about the most useful digital
voice recorder around; however, things are rapidly
changing. For instance, the Sony ICD-B7, which sold
new for under $50, has been reported to be an
excellent recorder for EVP. There are new models
from various manufacturers coming out nearly every
month and most will work very well. As a rule of
thumb, always use the longest recording time
setting. If the recorder has a very quiet sound
circuit, then you may need to add background noise
or enhance available noise with something like an
acoustical box to give you that "ocean in a sea
shell" effect. Please review
this
article for additional recommendations.
Question:
Do I need a recorder that has a
voice activated
recording mode?
Answer: The voice activation feature is a mixed blessing. Some experimenters use it and some refuse to. In some models, the Voice Activation (VOX) is slow and clips words. It will trigger on background noise and then as quickly turn off because the noise is not sufficient to keep it on. The result is a staccato sound between comments from the experimenter. You can often see the RECORD light flashing on and off with just the sound of a distant fan. We do use the RECORD light as an indicator that the recorder is on and may be recording an EVP. Watching the counter can provide the same information. One thing to watch for with VOX is that a phenomenal utterance may more or less fill the space between your comments, even though it is only a tenth of a second long and your pause was over thirty seconds. Thus, you can see that the communicating entity has used the noise caused by the VOX to form a voice. The rest of the story is that the timing of question and answer can be deceptive. We prefer VOX recording because of the time factor. It might take us thirty minute to review a three-to-five minute recording. Especially when we are field recording, it is possible to record for an hour or more, but with VOX, only have ten-to-fifteen minutes of recording to review. So the answer to your question is that the VOX feature is not necessary, but it can be helpful.
Question: How do I record audio files into my computer?
Answer: The newer recorders usually have a USB interface that allows easy transfer of files. Look for a model that records wav or mp3 files and avoid recorders using a proprietary format. If you have a device that doe snot permit each file transfer, it is possible to "play" the recording while the computer is in record mode. You will need a recording device with a headphone jack, or even better, a Line Out jack. The Line Out jack will connect to a computer Line In jack with an ordinary audio patch cord with a 1/8th inch stereo jack for the computer and whatever size that is required for your recorder. Computers use stereo jacks so that two channels can be recorded at once. Inexpensive recorders use mono jacks, so you may need to use a mono-to-stereo adapter. If you have only a headphone jack, then you may also require an audio patch cord that provides attenuation to match the 8 ohm headphone resistance with the usual 10K ohm Line in jack of your computer. We recommend that you take your recorder and speak to the clerk at Radio Shack or a similar electronics store. The modern equipment seems to automatically adjust the match so that you only need a plain cable. Make sure the computer is “looking” at the right jack. Line In and Microphone jacks are usually provided in a PC. The Line In jack is stereo, but the Microphone jack may be mono. In the Control Panel of your computer, open the Sound and Multimedia application. In the Audio tab, click on Volume and make sure the Line In volume control is selected.
Adobe Audition is a very good but costly audio
management program that is often used for recording
and editing audio files, but there are other
applications that do a good job as well. Audacity is
an excellent open source program and there are
setup instructions for this free program here.
The important features you will use are, reverse,
amplify, copy, cut, paste, filter and noise
reduction. Using these capabilities, it is common
for an experimenter to find a Class C (or less) EVP
in a sound file that no one else can understand, and
“clean it up” so that it is a Class A EVP that just
about anyone can understand. While this may pose
problems for scientific evaluation of these
phenomena, it is a most important capability for
personal use.
Question: How can I attach an EVP example to an email message? Answer: An EVP sound file is like any computer file and can be attached to an email in the same way that a text file is attached. As a consideration to others, the sound file should be made as small as possible if you expect the receiver to keep the file. It is best to use a audio management program such as Audacity to select the EVP and perhaps an associated question spoken by the practitioner. It is unreasonable to sending a long file with just a short utterance you wan them to hear. We recommend that the file be saved in your computer in the Wave format (*.wav) because that format retains the original data. For sharing files, we recommend the MP3 format because it is much smaller and takes up less room. MP3 does lose quality, so make sure that you "save as" the MP3 version to protect the original wave format. We usually use a Sample rate of 22050 KHz, Stereo, 16 Bits. We use stereo because we believe that we can hear the EVP better when using two ears. A Sample Rate of 22050 is sufficient to maintain the quality of your EVP; however, if you are trying to make your sound file smaller, save it as something like 8000 KHz, Mono, 8 Bit. (Always listen to the final version to be sure you have not corrupted the file.) A 8000 KHz sample rate will reasonably reproduce up to 4000 KHz, which is where most of the voice will be. it is also what the telephone company uses for voice circuits. Once your sample is saved as a Wave file of a reasonable size, and it has been named in a descriptive way, you can handle it just as a text file. It can be included as an attachment in an email message, or posted to a discussion board or on your website. If your sample has been modified in any way, it is a good idea to give a brief summary of those modifications in the posting or email message. It is also a good idea to tell how the recording was made, and why you believe the EVP is worth listening to in the first place. Since there are so many EVP samples offered on the Internet, it is a kindness to all if you post only the very best or most interesting. Of course, it is always reasonable to post an EVP that you need assistance with from the others, but tell the others of this need. Finally, always describe your attachment in the body of an email message. We routinely warn people not to open any attachment that has not been described in a reasonable way in the text of the email. This is an effort to avoid viruses, and so is a courtesy to others. Question: Should I buy a white-noise audio CD (not the movie!) as a source of background sound? Answer: White noise is a generic term used around the world by EVP experimenters. In actual practice, experimenters try to select sound sources that have more human voice frequencies. Experimenters commonly use something handy like a fan for background sound--anything that creates noise that is relatively steady-state, and that can then be filtered out. There is some evidence that noise with frequent changes, such as the sound of wind in the trees, is more useful. The transients appear to help begin an utterance. Sound generated by a computer, such as is often found in commercial sound CDs, has not proven to be as useful as the "live" noise one might find as natural background sound in a home. The reason we recommend cheap digital voice recorders is that some models produce a lot of internal noise with many transients, making it less necessary to supply noise. In fact, EVP can be recorded without a microphone if the recorder produces enough noise. Most experimental techniques for recording EVP are actually just novel ways of conditioning sound for voice formation. One of the ways to do this is to record a crowd of people speaking so that the recording has mostly human voice frequencies, but is still very rich in harmonics and changes in volume. If such a recording is carefully scrambled and then edited to make sure no recognizable syllables are present, the recording will provide excellent background sound for EVP. A Portuguese-language babble file used by Sonia Rinaldi is available here. Please note that the use of any recorded voice for background sound is fine for personal use but would not be accepted for research by a mainstream scientist. High frequency sounds tend to produce high frequency voices and it is possible to record simultaneous but different EVP in each layer of sound if you use, say a fan and a small water fountain. Question: Should I try using a diode as a detector for EVP? Answer: Early efforts to improve the quantity and quality of EVP messages included a large range of electronic devices and novel ways of using the equipment. One of the early attempts to improve over the microphone/recorder combination as a psi or EVP detector was the use of a diode/recorder combination, specifically a germanium diode. An unterminated transistor is a fine white noise generator and a transistor is a lot like three diodes. We find that the introduction of noise helps in voice formation, so using any noisy device might help. The second reason may be because of the Scole Experiments, during which the circle received instructions for a diode-like device to be used in place of a microphone--now known as the Scole Device. It did seem to help for EVP, but not so much that experimenter enthusiasm cannot be ruled out as an explanation for the improvement It is common for a new idea to work better than the usual recorders, but then to stop working better over time. This is probably due to the early enthusiasm of the experimenter. Some researchers have come to believe that improved equipment is not the way to improve reception. They believe that the best way is to improve the person doing the recording. One of the main reasons the ATransC has the NewsJournal, Archive, Idea Exchange and this public website is to teach people what has been tried before so that they may learn from the past and lead us all into new directions. We recommend that you consider trying something more current, such as seeking ways to modify the sound from which the voices are formed. Speech synthesis is showing considerable promise and the Association is attempting to design a computer program for EVP research.
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