In the figure below, we see that it has a wavelength twice as long as the flute. The frequency f equals the wave speed v divided by the wavelength l , so this longest wave corresponds to the lowest note on the instrument: C4 on a C foot instrument. Flutists please note: this page uses the standard note names , not the names sometimes used by flutists. Then check the answer in the note table.
You will find that the answer is only approximate, because of end corrections. You can play C4 on the flute with this fingering, but you can also play other notes by blowing harder, or by narrowing the lip aperture either gives a faster jet. These other notes correspond to the shorter wavelength standing waves that are possible, subject to the condition that the sound pressure be zero at both ends.
The first several of these are shown in the diagram below. The series of notes with frequency f o , 2f o , 3f o etc is called the harmonic series, and notes with these frequencies have the pitches shown below.
With all the tone holes closed, the first ten or so resonances of the flute are approximately in this ratio, so you can play the first seven or eight of the series by closing all the tone holes and blowing successively harder or by narrowing the lip aperture. Note the half sharp on the seventh harmonic - it falls roughly midway between A6 and A 6. You might be interested to compare this with the analogous diagram and sound files for the clarinet , which has only the odd harmonics present.
There is also a more detailed discussion of the harmonic series of open and closed pipes. Also see a warning about the words 'fundamental' and 'harmonic'. Eight 'harmonics' of the lowest note on a flute. Each of the standing waves in the sketch above corresponds to a sine wave.
The sound of the flute is a little like a sine wave a very pure vibration when played softly, but successively less like it as it is played louder. To make a repeated or periodic wave that is not a simple sine wave, one can add sine waves from the harmonic series. So C4 on the flute contains some vibration at C4 let's call its frequency f o , some at C5 2f o , some at G5 3f o , some at C6 4f o , etc. The 'recipe' of the sound in terms of its component frequencies is called its spectrum.
See sound spectrum for an explanation. Looking at real sound spectra for played C4 Open a new window for C4 you will see that, at pianissimo , the first harmonic fundamental and the frequency of the note C4 dominates, and that the higher harmonics become more important as the note is played more loudly, and as the flute develops a richer tone and sounds less and less like a sine wave.
For a detailed explanation, see Loudness and timbre. How the air jet and pipe work together To sum up the preceding sections: the bore of the flute has several resonances, which are approximately in the ratios of the harmonics, etc, but successively more approximate with increasing frequency--we'll see why below under frequency response. The air jet has its own natural frequency that depends on the speed and length of the jet.
To oversimplify somewhat, the flute normally plays at the strongest bore resonance that is near the natural frequency of the jet. We shall see below how register holes are used to weaken the lower resonance or resonances and thus make one of the higher resonances the strongest. When the flute is playing, the jet is oscillating at one particular frequency. But, especially if the vibration is large, as it is when playing loudly, it generates harmonics see What is a sound spectrum?
For low notes, the first several harmonics are supported by standing waves. However for high notes, the resonances of the flute are no longer harmonic, so only a small number of harmonicsonly one in the third and fourth octave are supported by resonances of the bore.
Played loudly however, harmonics of the vibration are present in the spectra, as you can see by looking at the spectra for any note.
Opening tone holes If you open the tone holes, starting from the far end, you make the pressure node move closer up the pipe - it's rather like making the pipe shorter. On the Boehm flute, each opened tone hole raises the pitch by a semitone. After you open 4 holes on a C foot flute, as shown below, you have the fingering for E4 , which is shown below. Open a new window for E4.
For the moment, we can say an open tone hole is almost like a 'short circuit' to the outside air, so the first open tone hole acts approximately as though the flute were 'sawn off' near the location of the tone hole. We shall return to qualify these assumptions below when we discuss register holes and cross fingerings. For the technically minded, we could continue the electrical analogy by saying that the open tone hole is actually more like a low value inductance, and so it behaves more like a short circuit at low frequencies than at high.
We return to this point when discussing cut-off frequencies below. Register holes Holes can also serve as register holes. For instance, if you play C4 and then lift your left thumb, you are opening a hole halfway down the instrument. This makes the fundamental and the odd harmonics impossible, but hardly affects the even harmonics, which have a node there.
So the flute 'jumps up' to C5 2f 1 , and will also play C6, G6 etc. Here the register hole makes the played note at least one octave higher, because it is halfway along the working length of the flute and so permits the second harmonic of the fundamental C4.
The example shown is not a standard fingering, but a register hole at half the length is used for the standard fingerings for D5 and others. When the desired wavelength is short i. For example, the fingering for D6 uses a register hole at approximately one third of the working length for G4, and so facilitates the third harmonic of G4 and thus produces a note a twelfth higher than G4.
The fingering for G6 also uses the working length for G4, but has a register hole about one quarter of the way along, and so facilitates the fourth harmonic. One of the alternative fingerings for D 6 uses the working length for D 4 but has two register holes, at one quarter and one half the wavelength. Notes in the third octaves of all flutes rely heavily on using tone holes as register holes.
Specific examples are explained on the pages for these notes. See Flute Acoustics and choose a note above D 6. Acoustic impedance of the flute The way in which the jet flows into and out of the flute depends upon the acoustic impedance at the embouchure hole, which is why we measure this quantity.
The acoustic impedance is the ratio of the sound pressure to the oscillating air flow. See Acoustic impedance for more detail. If the impedance is low, air flows in and out readily and a loud sound can be produced.
In fact, the resonances, which are the frequencies for which the acoustic impedance is very small, are so important that they 'capture' the behaviour of the air jet, and so the flute will play only at a frequency very close to a resonance. We discuss the acoustic impedance below, under Frequency response of the flute. There is further explanation on What is acoustic impedance and why is it important? Cross fingering On the modern or Boehm flute, successive semitones are played by opening a tone hole dedicated to that purpose.
There are twelve semitones in an octave, so that one needs to open twelve keys in a chromatic scale before going from say D4 in the first register to D5 in the second register. Twelve holes exceeds the number of fingers on standard players, particularly when the right thumb is employed to support the instrument.
Boehm's key system employs clutches so that one finger can close more than one hole. Flutes in the baroque and early classical periods had few keys. See The anatomy and evolution of the flute. They had six open holes covered by the three large fingers on each hand. The reflective plate is fixed in a position 17 mm from the center of the embouchure hole. Under normal circumstances, do not turn the crown head screw , as this will cause the reflective plate to slip out of place.
Breath injected into the flute strikes the reflective plate and is directed to the right. The quality of the cork influences the quality of the sound. The head joint tube narrows toward its left end. This is described as a tapered tube.
In musical instrument terminology, "tapering" refers to the manner in which a tube opens out. Yamaha manufactures three different types of tapered tube. A G-tapered tube essentially expands evenly in diameter from the thin end to the thick end. It offers a strong resistance when blown and produces a deep sound. A C-tapered tube has a streamlined shape like a liquor bottle. It is easy to blow into and produces a light timbre.
The shape of a Y-tapered tube is a combination of the G- and C-tapered tube shapes, offering moderate resistance when blown and producing a delicate sound. There are also a number of variations to the cut of the embouchure hole. First, the embouchure hole can be cut square or rounded, and there can be variation in the amount of shoulder cut or undercut.
The nature of the tapering determines the most suitable cut for the embouchure hole, which, in turn, greatly affects the feel of the instrument when you play it.
The exact size, shape, and position of the keys and tone holes must be accurate to ensure that they will fit together correctly. The completed instrument is played by an experienced musician to ensure that it produces sound correctly. Because professional musicians often make special demands of flutes, flutemakers will often make small adjustments in flutes to satisfy them.
Much of the responsibility for maintaining the quality of a flute rests with the musician. Routine maintenance often prevents flaws from developing. Each time the flute is assembled, the connecting surfaces of the Most flutes are made of metal.
All flutes are individually assembled and play tested prior to sale. The interior of the flute should be swabbed each time it is played to remove moisture, which could cause the pads to swell so that they no longer fit the tone holes. Careful lubrication of the keys with a special lubricant is necessary about every three to six months in order to keep them working smoothly.
Very few changes have been made in the basic design of the modern transverse flute since the middle of the nineteenth century. Flutemakers will continue to find ways to make small but critical changes in individual instruments to fit the needs of individual musicians. Two seemingly opposite trends hint at the future of flutemaking. Many performers of music from the Renaissance, Baroque, and Classical periods prefer to use flutes that resemble the instruments used during those times.
Such instruments are believed to be more suited to older music than modern flutes, which developed during the Romantic period. On the other hand, many performers of jazz, rock, and experimental music use electronic devices to alter the sounds of flutes in new ways. Despite these two trends, the instrument originally designed by Theobald Bohm is likely to dominate flutemaking for many years to come.
Meylan, Raymond. The Flute. Amadeus Press, Wong, Kate. Toggle navigation. Made How Volume 5 Flute Flute. Flutes are comprised of hundreds of components, ranging from the relatively large body to tiny pins and screws.
The keys are die cast and fitted with pads made from layers of cork and felt. Tone holes are formed in the body of the flute by either pulling and rolling or by cutting and soldering. In the pulling and rolling method, the holes are drilled in the tube, and a machine pulls the metal from the edges of the hole and rolls it around the hole to form a raised ring.
If the tone holes are to be cut and soldered, die cut metal rings are soldered to the drill holes. This is done by opening a hole in the side of the tube.
The vibrating portion of the tube will always be at least on the first octave between the mouth hole and the first open hole beneath it. The total amount of expansion or contraction on a given note exaggerated in the illustrations is an average of one fiftieth of an inch, with an individual molecule moving in either direction only half that distance! As an example, lets close up the holes in the tube again and take a look at the first harmonic. It looks something like this:.
All these ways of vibrating are occurring in the flute tube at the same time. And if we open holes in the tube, all these vibrational patterns will then be occurring between the mouth hole and the first open hole beneath it. How is it possible for all these vibrations to be happening simultaneously?
To understand this it might help to think of these vibrations not so much as actual movements of the air, but as the movement of forces that act on the air. If the two forces were going in the same direction, it would move in that direction an extra amount. You can send a vibration down the rope, then another one shortly after.
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