Five-key flute

The five-key flute is a musical instrument once common in school marching bands, and composed of wood with metal keys. It is a transposing instrument, most commonly in Bb, this variant being known as the Bb flute and sounding one tone below the orchestral piccolo. The next most common variant is the Eb flute, sounding a fifth below the Bb flute and used as its bass instrument in band harmonies. It is now often found in British military corps of drums, often playing various regimental marches.

As the name suggests, the five-key flute most commonly has five keys, as do many historic 19th century French and German simple system flutes. Simple system keying on wooden tapered bore flutes was the standard orchestral instrument before It was eventually replaced by the Boehm cylindrical bored flute keying system. See Boehm System. It evolved from the baroque one key transverso flute. The four key flute preempted the five key, and it progressed thru multiple keyed flutes. It uses the six-hole fingering system of the fife for its natural scale, with the metal keys adding the ability to play the full chromatic scale and therefore making it possible to play in any key.

The keys of the Bb flute are (starting with the hole closest to the mouthpiece):

The keys of the 19th century five key D flute include an Eb key, F key, G# key and either a C key or a long left hand additional F key.

The modern five-key flute is conical in bore, with a cylindrical head joint and a body that tapers to become narrowest furthest from the mouthpiece.

French five-key flutes were once the preferred flute for use in charanga bands due to their distinct tone and facility in their third and fourth octave

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