The flute is a transverse (or side-blown) woodwind instrument that is closed at the blown end. It is played by blowing a stream of air over the
embouchure hole. The pitch is changed by opening or closing keys that cover circular
tone holes (there are typically 16 tone holes). Opening and closing the holes produces higher and lower pitches. Higher pitches can also be achieved through over-blowing, like most other woodwind instruments. The direction and intensity of the airstream also affects the pitch, timbre, and dynamics. The
piccolo is also commonly used in Western orchestras and bands.
Alto flutes, pitched a fourth below the standard flute, and
bass flutes, an octave below, are also used occasionally. :(B3)
C4–C7 (F7) The standard concert flute, also called
C flute,
Boehm flute,
silver flute, or simply
flute, is pitched in C and has a potential range of three and a half octaves starting from the note C4 (
middle C). The flute's highest pitch is usually given as C7 or (in more modern flute literature) D7. More experienced flautists are able to reach up to F7, but notes above D7 are difficult to produce. Modern flutes may have a longer foot joint, a
B-footjoint, with an extra key to reach B3. From high to low, the
members of the concert flute family include the following: •
Piccolo in C or D •
Treble flute in G •
Soprano flute in E • Concert flute in C, described above •
Flûte d'amour (also called
tenor flute) in B, A, or A •
Alto flute in G •
Bass flute in C •
Contra-alto flute in G •
Contrabass flute in C (also called
octobass flute) •
Subcontrabass flute in G (also called
double contra-alto flute) or C (also called
double contrabass flute) •
Double contrabass flute in C (also called
octocontrabass flute or
subcontrabass flute) •
Hyperbass flute in C Each of the above instruments has its own range. The piccolo reads music in C (like the standard flute), but sounds one octave higher. The alto flute is in the key of G, and the low register extends to the G below middle C; its highest note is a high G (4
ledger lines above the treble staff). The bass flute is an octave lower than the concert flute, and the contrabass flute is an octave lower than the bass flute. Less commonly seen flutes include the treble flute in G, pitched one octave higher than the alto flute; soprano flute, between the treble and concert; and tenor flute or flûte d'amour in B, A or A pitched between the concert and alto. Flutes pitched lower than the bass flute were developed in the 20th century. These include the
contra-alto flute (pitched in G, one octave below the alto), the
subcontrabass flute (pitched in G, two octaves below the alto), and the
double contrabass flute (pitched in C, one octave below the contrabass). The flute sizes other than the concert flute and piccolo are sometimes called
harmony flutes.
Construction and materials Concert flutes have three parts: the
headjoint,
body, and
foot joint. The headjoint is sealed by a cork (or plug that may be made out of various plastics, metals, or less commonly woods). It is possible to make fine adjustments to tuning by adjusting the headjoint cork, but usually it is left in the factory-recommended position around from the centre of the
embouchure hole for best scale. Gross, temporary adjustments of pitch are made by moving the headjoint in and out of the headjoint tenon. The flautist makes fine or rapid adjustments of pitch and timbre by adjusting the
embouchure and/or position of the flute in relation to himself or herself, i.e., side and out. • Crown – the cap at the end of the head joint that unscrews to expose the cork and helps keep the head joint cork positioned at the proper depth. • Lip plate – the part of the head joint that contacts the player's lower lip, allowing positioning and direction of the air stream. • Riser – the metal section that raises the lip plate from the head joint tube. • Head joint – the top section of the flute, it has the tone hole/lip plate where the player initiates the sound by blowing air across the opening. • Body – the middle section of the flute with the majority of the keys. • Closed-hole – a fully covered finger key. • Open-hole – a finger key with a perforated center. • Pointed arms – arms connecting the keys to the rods, which are pointed and extend to the keys' centers. These are found on more expensive flutes. • French model – a flute with pointed French-style arms and open-hole keys, as distinguished from the plateau style with closed holes. • Inline G – the standard position of the left-hand G (third-finger) key – in line with the first and second keys. • Offset G – a G key extended to the side of the other two left-hand finger keys (along with the G key), making it easier to reach and cover effectively. • Split E mechanism – a system whereby the second G key (positioned below the G key) is closed when the right middle-finger key is depressed, enabling a clearer third octave E; omitted from many intermediate- and professional flutes, as it can reduce the tonal quality of the third-octave F (F6). • Trill keys – two small teardrop shaped keys between the right-hand keys on the body; the first enables an easy C–D trill, and the second enables C–D. A–B lever or "trill" key is located in line directly above the right first-finger key. An optional C trill key that facilitates the trill from B to C is sometimes found on intermediate- and professional flutes. The two trill keys are also used in playing the high B and B. • Foot joint – the last section of the flute (played farthest towards the right). • C foot – a foot joint with a lowest note of middle C (C4); typical on student flutes. • B foot – a foot joint with a lowest note of B below middle C (B3), which is an option for intermediate and professional flutes. • D roller – an optional feature added to the E key on the foot joint, facilitating the transition between E/D and D/C, and C. • "
Gizmo key" – an optional key on the B foot joint that helps play C7.
Head joint shape The head-joint tube is tapered slightly towards the closed end. Theobald Boehm described the shape of the taper as parabolic. Examination of his flutes did not reveal a true parabolic curve, but the taper is more complex than a truncated cone. The head joint is the most difficult part to construct because the lip plate and tone hole have critical dimensions, edges, and angles that vary slightly between manufacturers and in individual flutes, especially where they are handmade. Head joint geometry appears particularly critical to acoustic performance and tone, but there is no clear consensus on a particular shape amongst manufacturers. Acoustic impedance of the
embouchure hole appears to be the most critical parameter. Critical variables affecting this acoustic impedance include: chimney length (the hole between lip-plate and head tube), chimney diameter, and radiuses or curvature of the ends of the chimney. Generally, the shorter the hole, the more quickly a flute can be played; the longer the hole, the more complex the tone. Finding a particularly good example of a flute is dependent on play-testing. Head joint upgrades are usually suggested as a way to improve the tone of an instrument. Cheaper student models may be purchased with a curved head to allow younger children with shorter arms to play them.
Tubing materials Less expensive flutes are usually constructed of
brass,
polished and then silver-plated and
lacquered to prevent
corrosion, or silver-plated
nickel silver (nickel-bronze
bell metal, 63%
Cu, 29%
Zn, 5.5%
Ni, 1.25%
Ag, .75%
Pb, alloyed
As,
Sb,
Fe,
Sn). Flutes that are more expensive are usually made of more precious metals, most commonly solid
sterling silver (92.5% silver), and other alloys including French silver (95% silver, 5% copper), "
coin silver" (90% silver), or
Britannia silver (95.8% silver). It is reported that old Louis Lot French flutes have a particular sound by nature of their specific silver alloy. Gold/silver flutes are even more expensive. They can be either gold on the inside and silver on the outside, or vice versa. All-gold and all-platinum flutes also exist. Flutes can also be made out of wood, with African blackwood (grenadilla or
Dalbergia melanoxylon) being the most common today.
Cocuswood was formerly used, but this is hard to obtain today. Wooden flutes were far more common before the early 20th century. The silver flute was introduced by Boehm in 1847, but did not become common until later in the 20th century.
William S. Haynes, a flute manufacturer in Boston, Massachusetts, United States, told
Georges Barrère that in 1905 he made one silver flute to every 100 wooden flutes, but in the 1930s, he made one wooden flute to every 100 silver flutes. Unusual tubing materials include
glass,
carbon fiber, and
palladium. Opinions on how different materials affect sound quality vary widely. Flute maker
Verne Q. Powell stated that "As far as tone is concerned, I contend that 90 percent of it is the man behind the flute". Most metal flutes are made of alloys that contain significant amounts of copper or silver. These alloys are biostatic because of the
oligodynamic effect and thus suppress growth of unpleasant
molds, fungi, and bacteria. Good quality flutes are designed to prevent or reduce
galvanic corrosion between the tube and key mechanism.
Pad materials Tone holes are stopped by pads constructed of "fish skin" (
goldbeater's skin) over felt, or sometimes silicone rubber on some low-cost or "ruggedized" flutes. Accurate shimming of pads on professional flutes to ensure pad sealing is very time consuming. In the traditional method, pads are seated on paper shims sealed with
shellac. A recent development is "precision" pads fitted by a factory-trained technician. Student flutes are more likely to have pads bedded in thicker materials like wax or hot-melt glue. Larger-sized closed-hole pads are also held in with screws and washers.
Keywork The keys can be made of the same or different metals as the tubing, nickel silver keys with silver tubing, for example. Flute key axles (or "steels") are typically made of drill rod or stainless steel. These mechanisms need periodic disassembly, cleaning, and relubrication, typically performed by a trained technician, for optimal performance. James Phelan, a flute maker and engineer, recommends single-weight motor oil (SAE 20 or 30) as a key lubricant demonstrating superior performance and reduced wear, in preference to commercial key oils). The keywork is constructed by lost-wax castings and machining, with mounting posts and ribs silver-soldered to the tube. On the best flutes, the castings are forged to increase their strength. Most keys have needle springs made of
phosphor bronze,
stainless steel,
beryllium copper, or a
gold alloy. The B thumb keys typically have flat springs. Phosphor bronze is by far the most common material for needle springs because it is relatively inexpensive, makes a good spring, and is resistant to corrosion. Unfortunately, it is prone to metal fatigue. Stainless steel also makes a good spring and is resistant to corrosion. Gold springs are found mostly in high-end flutes because of gold's cost.
Mechanical options ; B thumb key:The B thumb key (invented and pioneered by
Briccialdi) is considered standard today. These holes are covered by the fingertips when the keys are depressed. Open-hole flutes are frequently chosen by concert-level flautists, although this preference is less prevalent in Germany, Italy, and Eastern Europe. Students may use temporary plugs to cover the holes until they can reliably cover the holes with the fingertips. Some flautists claim that open-hole keys permit louder and clearer sound projection in the lower
register. Open-hole keys are needed for ethnic styles such as traditional Celtic music, and for some modern concert pieces that require harmonic overtones or "breathy" sounds. They can also facilitate alternate fingerings,
extended techniques such as
quarter-tones,
glissandi, and multiphonics. Closed holes (plateau keys) permit a more relaxed hand position for some flautists. ; Offset G versus in-line G keys: All of Boehm's original models had offset G keys, which are mechanically simpler, and permit a more relaxed hand position, especially for flautists with small hands. Some players prefer the hand position of the in-line G. For many years there was a misperception that inline G was for "professional" flutes while offset G was for "student" models, but this stereotype has been largely debunked. ; Split E: The split E modification makes the third octave E (E6) easier to play for some flautists. A less expensive option is the "low G insert". ; B foot: The B foot extends the range of the flute down one semitone to B3 (the B below middle C). ; Gizmo key: Some flutes with a B foot have a "
gizmo key": a device that allows closure of the B tone hole independently of the C and C keys. The gizmo key makes C7 easier to play. Some higher notes (third-octave B and B and most fourth-octave notes) also require use of the two lower trill keys. A fourth so-called C trill key is an increasingly popular option available on many flutes. It is named after one of its uses, to ease the B to C trill, but it also allows some trills and tremolos that are otherwise very difficult, such as high G to high A. Another way of trilling G6–A6 is a dedicated high G–A trill key. ; D roller: Some models offer a D roller option, or even an optional pair of parallel rollers on the D and C keys, that ease motion of the right little finger on, for example, low C to D. ; Soldered tone holes: Tone-holes may be either drawn (by pulling the tube material outwards) or soldered (cutting a hole in the tube and soldering an extra ring of material on). Soldered tone-holes are thought by some to improve tone, but generally cost more. ; Scale and pitch: The standard pitch has varied widely over history, and this has affected how flutes are made. Although the standard
concert pitch today is A4 = 440 Hz, many manufacturers optimize the tone hole size/spacings for higher pitch options such as A4 = 442 Hz or A4 = 444 Hz. (As noted above, adjustments to the pitch of one note, usually the A4 fingering, can be made by moving the headjoint in and out of the headjoint tenon, but the point here is that the mechanical relationship of A4 to all other pitches is set when the tone holes are cut. However, small deviations from the objective 'mechanical' pitch (which is related to acoustic impedance of a given fingering) can be improvised by
embouchure adjustments.) == Composition ==