Frequency

As an auditory definition, frequency is defined as the phenomena of sound energy created by vibration. It is related to but distinct from <a title="Pitch" href="../2014/12/pitch/">pitch</a>. Frequency is the measurement of vibrations and is often described as part of a range of frequencies that humans can hear. <em>Typical range of human hearing:</em> <table style="height: 92px;" border="1" width="509" cellspacing="0" cellpadding="10" align="left"> <tbody> <tr> <td> <div style="text-align: center;">&lt;20 Hz</div></td> <td> <div style="text-align: center;">20-20kHz</div></td> <td> <div style="text-align: center;">&gt;20kHz</div></td> </tr> <tr> <td> <div style="text-align: center;"><strong>sub-audio rate</strong></div></td> <td> <div style="text-align: center;"><strong>audio rate</strong></div></td> <td> <div style="text-align: center;"><strong>ultrasonic</strong></div></td> </tr> </tbody> </table> &nbsp; &nbsp; &nbsp; <h5>Examples:</h5> <ul> <li>Animals, like our dogs, can hear a different range of frequencies. So something designed for your pet might play a noise at an imperceptible frequency to get their attention but not disrupt their owners.</li> </ul> &nbsp; <hr /> <ol> <li><span style="color: #999999;"><a style="color: #999999;" href="http://www.indiana.edu/~emusic/acoustics/frequency.htm" target="_blank">"What is frequency?" Indiana University</a></span></li> <li><span style="color: #999999;">[Image source] <a style="color: #999999;" href="https://itunes.apple.com/us/app/spectrum-analyzer-real-time/id490078884?mt=8" target="_blank">Spectrum Analyzer - Real Time Sound Frequency Analyzer</a></span></li> </ol>