THE SCIENCE OF SOUND
'<a href="http://www.j-archive.com/media/2007-05-17_DJ_30.jpg" target="_blank">(Cheryl of the Clue Crew presents from the NCPA at Mississippi)</a><br />Using the same prefixes as for light, the sonic spectrum goes from ultrasound to <a href="http://www.j-archive.com/media/2007-05-17_DJ_30a.jpg" target="_blank">these</a> waves that are too low in frequency to hear; the mics being used here can pick them up'
infrasound