When the vocal cords come together precisely, a pure & clear sound is produced. However, if there are any rough edges, swellings, or masses on the vocal cord (ie, vocal cord nodules, polyps, cysts, etc), the vibration becomes disrupted creating an absent, harsh, or raspy sounding voice. Sometimes this occurs only at a specific pitch.
The best analogy would be a violin string. Imagine playing a single tone on the violin. Now imagine a fly landing on the string. Such an event would disrupt the sound the violin produces. Another situation arises when the vocal cords don't come together at all. In this scenario, vibration is barely produced at all resulting in a breathy sounding voice.The library of video and audio samples will illustrate each of these different scenarios. Be aware that you need QuickTime plugin installed in order to listen and watch the samples. Be patient when waiting for the webpages to load as the video samples are several megabytes in size. Alternatively, the Photo Library section contains pictures (instead of video) of various voicebox abnormalities.
Back to the beginning of the human voice tutorial.
Any information provided on this Web site should not be considered medical advice or a substitute for a consultation with a physician. If you have a medical problem, contact your local physician for diagnosis and treatment.