Bass flute
The bass flute is the bass member of the flute family. It is in the key of C, pitched one octave below the concert flute. Because of the length of its tube (approximately 146 cm (57 in)), it is usually made with a J-shaped head joint, which brings the embouchure hole within reach of the player. It is usually only used in flute choirs, as it is easily drowned out by other instruments of comparable register, such as the clarinet.
Prior to the mid-20th century, the term "bass flute" was sometimes used, especially in Great Britain, to refer to the alto flute instead (for example: the part for "bass flute in G" in Gustav Holst's The Planets). In 1910 Abelardo Albisi invented a bass flute known as the albisiphone which was used in scores by Mascagni and Zandonai among other composers during the first half of the 20th century.
The instrument's sounding range is from C3, one octave below middle C, to C6, two octaves above middle C. Bass flute music sounds an octave lower than it is written, which is the typical concert flute range (C4 to C7). Notes written above A6 are not often used as they are difficult to produce and have inferior tone. Because manufacturers do not taper the flute body through the curve, intonation of all notes beginning with written D6 and higher tend to be sharp. The player can bend them in tune through blowing technique or use alternative fingerings.
Bass flutes often have a C foot rather than the B foot common to other flutes. The shorter tube reduces acoustic resistance, which quickens the response and makes the tone brighter, livelier, and more resonant. The shorter tube also makes the instrument somewhat lighter and less fatiguing for the player to hold.
Bass flutes are most often made with silver-plated bodies and head joints. Most basses come with trill keys which allow the player to stabilize some otherwise unstable middle register notes as well as trill between otherwise impossible notes. Kotato basses have addressed the weight problem of bass flutes by designing a graphite rod that screws onto the underside of the instrument and then rests on the chair seat between the player's legs. Adjustable rods have also been developed by Jeff Amos. Other manufacturers have added a left hand thumb support called a crutch, which helps some players with physical control of the instrument.
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