Musical saw

A musical saw, also called a singing saw, is a hand saw used as a musical instrument. Capable of continuous glissando (portamento), the sound creates an ethereal tone, very similar to the theremin. The musical saw is classified as a friction idiophone with direct friction (131.22) under the Hornbostel-Sachs system of musical instrument classification. First played in America.

The saw is generally played seated with the handle squeezed between the legs, and the far end held with one hand. Some sawists play standing, either with the handle between the knees and the blade sticking out in front of them. The saw is usually played with the serrated edge, or "teeth", facing the body, though some players face them away. Some saw players file down the teeth which makes no discernable difference to the sound. Many—especially professional—saw players use a handle at the tip of the saw for easier bending and higher virtuosity.
To sound a note, a sawist first bends the blade into an S-curve. The parts of the blade that are curved are damped from vibration, and do not sound. At the center of the S-curve a section of the blade remains relatively flat. This section, the "sweet spot", can vibrate across the width of the blade, producing a distinct pitch: the wider the section of blade, the lower the sound. Sound is usually created by drawing a bow across the back edge of the saw at the sweet spot, or sometimes by striking the sweet spot with a mallet. The sawist controls the pitch by adjusting the S-curve, making the sweet spot travel up the blade (toward a thinner width) for a higher pitch, or toward the handle for a lower pitch. Harmonics can be created by playing at varying distances on either side of the sweet spot. Sawists can add vibrato by shaking one of their legs or by wobbling the hand that holds the tip of the blade. Once a sound is produced, it will sustain for quite a while, and can be carried through several notes of a phrase.
On occasion the musical saw is called for in orchestral music, but orchestral percussionists are seldom also sawists. If a note outside of the saw's range is called for, an electric guitar with a slide can be substituted.

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