As a paranormal investigator practicing ITC, you'll often be required to analyze audio recorded during investigations in order to determine if any spirit voices or audible phenomena have been captured in the recording. Proper analysis of the audio requires you to understand terms like frequency, amplitude, wavelength, and pitch.

13The best way to analyze a waveform is with software such as Adobe Audition or Audacity. These applications allow you to view the waveform, zoom into it, pick out sounds in the recordings, and amplify them. When looking at a waveform as a whole recording, it's hard to pick out anything useful, as the image above shows. However, it is clear to see areas of loud noise and silence.

Sound waves in a recording will normally be fluctuating vibrations consisting of many different frequencies and amplitudes, but to simplify things, we're going to introduce you to the parts of a uniform oscillating wave.14In...