Tennessee Spirit Mike Manual

Thank you for your purchase of the Tennessee Spirit Mike. You will find the mike fully assembled and tested, but will need to install batteries prior to use. The unit requires 2 standard 9 V rectangular style batteries. We recommend using alkaline batteries for the best cost performance ratio.

1. Remove the four screws in the four corners of the box. (If there are no screws, then you will find them in a bag inside the box).
2. Carefully lift off the top of the box.
3. Make sure that the switch is off (in the down position), and connect the
two battery clips to the batteries.
4. Turn the switch on for a moment and verify that the LED lights. Turn back off.
5. Align the batteries so that the clips are in the middle of the box as shown in the photo and press the batteries into the mounting clips.
6. Carefully replace the top of the box, making sure to not pinch or catch any wires.
7. Replace the 4 screws removed earlier, and verify that LED still lights when turned on.

Inside the Tennessee Spirit Mike

To use the box you will need to connect it to a recorder or amplifier. The audio is output on a standard 1/8 " mono phono jack. Use a cable to connect the output to a computer, recorder or amplifier. The output impedence is low, so you can split the signal and run to both an amplifier and recorder at the same time if desired. Output level is standard LINE level, and works well for both running into the LINE input of a computer, amplifier, or recorder. If the recorder has a high and low sensitivity setting, then set it to low to prevent saturation of its input stage. Avoid placing the unit on anything that is vibrating when in use.

We highly recommend running a normal voice recorder in conjunction with the spirit mike when investigating. Because the background noise will be attenuated, and the EVPs amplified in the Spirit Mike, the standard recorder makes a good control to help determine whether something recorded was an EVP or background noise or talking.

Note that the expected battery life of the standard unit is approximagely 50 hours of operation. The unit will work with the batteries as low as 6 volts, but they should be replaced before they run down. The LED on the front cannot be used to determine battery life, one battery can be totally dead, but the lamp will still light if the other battery is good. However if one battery is dead, the unit will not work. It is very easy to verify that the unit is working by tapping on it and listening to it with a headphone. If you use a stereo headphone, it is normal to only hear it in the left channel since it has a mono output.

Note that the Sensor is a gravity wave sensor. It is made up of a special electret sensor surrounded by material which absorbs gravity waves and converts them to vibrations. The material is also selected to absorb and attenuate audio vibrations. The density and thickness is chosen to optimize the losses of audio pickup with the maximum EVP pickup. Basically with no material, you have maximum audio pickup and some EVP pickup. When the material is added, audio pickup drops, but EVP pickup increases. At the optimum thickness, the EVP pickup peaks, and further increases in the thickness will reduce the EVP pickup. This is because the gravitation waves will end up being absorbed and converted to vibrations too far from the sensor, and the vibrations will then be attenuated just as the audio is. It is possible to actually put so much material around the sensor so that neither audio nor EVP can be received. Thus wrapping the unit in additional sound proofing material can actually cause a loss of sensitivity and S/N ratio of the unit.

For additional pointers on obtaining EVPs in an investigation we recommend that you read How to Record EVPs