Some people ask about what a different between frequencies, its most asking by the sound engineer or other sound enthusiast, now we can get the answer online.
This hearing test measures the relative sensitivity of your ears at different frequencies. It produces equal loudness contours or hearing sensitivity curves – the frequency response of your own ears. The flash script allows you to play sound files with a range of frequencies and sound levels with the click of a mouse. The total size of all files is approximately 400 k. Because both the chart and the instructions refer to decibels, you may wish to go first to What is a decibel?
Read more : http://www.phys.unsw.edu.au/jw/hearing.html
