Although most people regard slide whistle as a sound effect, it is actually a musical instrument that can be a lot of fun to play. Known also as a Swanee whistle, piston flute or "bicycle pump,” it’s an oddball member of the woodwind family that works much like the trombone, a brass horn. Notes are sounded by blowing into the “fipple,” or mouthpiece, while sliding the “piston” or “plunger” at the other end of the whistle’s tubular body in and out. There are no keys to press, note markings to watch nor holes to cover. It’s played entirely by ear.
Produce a drop in pitch from high to low by starting with the plunger all the way in. Hold the whistle with one hand, and place your lips around the mouthpiece. Blow into the mouthpiece, while sliding the plunger out with your other hand.
Begin with the plunger all the way out to produce a rise in pitch from low to high. Do the same as in Step 1, but slide the plunger in as you blow into the whistle's mouthpiece.
Pull the plunger out about halfway and begin at this pitch to play melodies. Blow into the whistle, moving the plunger in for higher notes and out for lower ones. Adjust your starting point if you run out of notes while trying to play a particular song.
Use moderate and consistent breath to produce a bright, sweet note. Blowing too hard causes the whistle to shriek and not enough wind creates an airy, hollow sound.
There is less distance between notes as you rise up the scale, sliding the plunger into the whistle. High notes have less space between neighboring pitches than low notes on the instrument.
Start with simple songs, such as “Three Blind Mice,” “Mary Had A Little Lamb,” “Frere Jacques” and “Twinkle, Twinkle, Little Star,” to familiarize yourself with the position of the notes. Increase song complexity, as you get the hang of it and develop a feel for the instrument.
Professional quality slide whistles are inexpensive.
Take your time and have fun.
Handle the plunger with care as you move it in and out, especially if you have a quality slide whistle. Pulling the plunger with force, or twisting it, can damage the instrument and make it unplayable.