Whistling

Whistling without the use of an artificial whistle is achieved by creating a small opening with one's lips and then blowing or sucking air through the hole. The air is moderated by the lips, curled tongue, teeth or fingers (placed over the mouth) to create turbulence, and the mouth acts as a resonant chamber to enhance the resulting sound by acting as a type of Helmholtz resonator.

Pucker whistling is the most common form in much Western music. Typically, the tongue tip is lowered, often placed behind the lower teeth, and pitch altered by varying the position of the tongue. In particular, the point at which the tongue body approximates the palate varies from near the uvula (for low notes) to near the alveolar ridge (for high notes). Although varying the degree of pucker will change the pitch of a pucker whistle, expert pucker whistlers will generally only make small variations to the degree of pucker, due to its tendency to affect purity of tone. Pucker whistling can be done by either only blowing out or blowing in and out alternately. In the 'only blow out' method, a consistent tone is achieved, but a negligible pause has to be taken to breathe in. In the alternating method there is no problem of breathlessness or interruption as breath is taken when one whistles breathing in, but a disadvantage is that many times, the consistency of tone is not maintained, and it fluctuates.

Many expert musical palatal whistlers will substantially alter the position of the lips to ensure a good quality tone. Venetian gondoliers are famous for moving the lips while they whistle in a way that can look like singing. A good example of a palatal whistler is Luke Janssen, winner of the 2009 world whistling competition.

Finger whistling or wolf-whistling is harder to control but achieves a piercing volume. In Boito's opera Mefistofele the title character uses it to express his defiance of the Almighty.

Whistling can also be produced by blowing air through enclosed, cupped hands or through an external instrument, such as a whistle or even a blade of grass or leaf.

One of the most well known whistling competitions is the International Whistlers Convention (IWC). Since 1973, this annual event takes place in Louisburg, North Carolina. The awards go to whistlers ranging from international male and female, teenage male and female, and even grandchildren. It has been customary for the Governor of the State of North Carolina to sign a declaration declaring the week of the IWC as "Happy Whistlers Week," for citizens and visitors to honor the art of whistling and to participate in the scheduled events.

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Wikipedia