# Brass instrument

A brass instrument is a wind instrument in which the notes are blown with a kettle or funnel mouthpiece according to the principle of the upholstered pipe. The vibrating lips of the musician generate the sound by coupling it to a conical-cylindrical tube whose air column serves as a resonator . Terminologically more correct is the term “lip tone instrument”, which, according to the Hornbostel-Sachs system, belongs to the class of actual wind instruments in the aerophone group . Well-known brass instruments in European culture include horn (French horn) , hunting horn , trumpet , trombone , cornet , flugelhorn , alto horn , tenor horn , baritone horn and tuba .

## Importance of the material

The majority of brass instruments are made of sheet metal from metal alloys such as brass or nickel silver . However, the material is not decisive for the categorization. Modern fiber composites are used in large instruments such as the Sousaphone to save weight. The modern vuvuzela is made of plastic.

Wooden instruments such as the alphorn or the didgeridoo work according to the same principle, but in common parlance, like the serpents and tines with tone holes , historically they are not counted among the brass instruments, but are considered to be lip-tone instruments.

The flap horn and the ophicleide , on the other hand, are generally recognized as brass instruments with regard to their history of development. They are also blown with a kettle mouthpiece.

The saxophone and the flute, on the other hand, belong to the group of woodwind instruments because of their sound production , although their body is usually made of metal.

## Principle of sound generation

Most musical instruments consist of a vibration generator (generator) and a vibration amplifier (resonator). The peculiarity of the brass instruments is that the vibrations are generated by the lips of the wind player and thus a human organ becomes part of the instrument. The air is blown evenly through the lips, which are slightly tensioned against the current. If the flow velocity is sufficient, the lip tissue starts to vibrate due to the resistance of the muscles. The transition of the vibration of the lips to the sound column happens through the mouthpiece .

## Physics of sound generation

Standing waves (from bottom to top first to fifth natural tone ) in a conical tube open on one side; dark = maximum, light = minimum of the pressure amplitude. Because of the conical shape, the distances from one maximum to the next are not the same and are not a measure of the wavelength of the emitted sound

A brass instrument functions as an upholstered pipe . The sound is created by the vibration of the blower's lips adjusting to one of the natural frequencies of the air column in the instrument, which is determined by the length of the pipe . By resonance device with the air column in the pipe it into vibration and creates a standing wave . Their vibration is transmitted to the ambient air at the open end of the pipe via the bell. In order to achieve the best possible sound result (as many partials / overtones as possible ), the lip frequency must be congruent with the frequency of the respective natural tone. If, without leaving the natural tone , the initializing frequency of the lips is too high or too low, the standing wave is shortened or lengthened, whereby the frequency of the tone is "falsified" higher or lower.

The instrument is usually composed of various conical and cylindrical pieces, but physically it essentially acts like a conical tube closed at the narrow end by the player's mouth. The lowest tone that can be generated therefore has a wavelength that is about twice the length of the instrument. At the next higher natural frequency, i.e. the second natural tone , the wavelength is the same as the instrument length, i.e. the tone is an octave higher.

Overall, the natural frequencies result in the well-known series of natural tones . It is identical to the partial tone series of the fundamental tone. By adjusting the oscillation frequency by accelerating the flow speed of the air through the lip gap, brass instruments overblow to the tone whose frequency is the nearest whole-number multiple of the frequency of the fundamental tone. Two, three, four or more half waves occur in the pipe. Whether the fundamental is practically usable depends, among other things, on the type and length of the instrument (see below) of the instrument (see below, half instrument / full instrument).

The highest playable note depends on the ability of the wind player; however, the mouthpiece has a strong influence on it. Smaller mouthpieces with a narrower bore make it easier to address higher tones, but lead to a sharper sound, especially in the lower registers.

## Blowing technique of sound generation

The sound quality depends on many factors. In addition to the construction and material properties of the instrument, the dexterity and physical constitution of the wind player are essential factors. In order to establish the congruence of the initializing vibration of the lips with the frequency of the natural tone determined by the length of the pipe, as described above under the physics of tone generation , an optimal balance is required between

• the flow velocity of the air through the lip gap,
• the size of the gap between the lips and the
• Tissue resistance (muscle tension) of the lips.

The less stressed the lips vibrate according to the required pitch due to internal muscle tension and mouthpiece pressure, the cleaner and clearer the tone sounds. The air flow built up and controlled by the breathing support , by the diaphragm , abdominal muscles ( pelvic floor muscles , abdominal wall ) and the back muscles (flanks) as an energy source is of greatest importance here, because the vibration is initialized and carried by the energy of the air flowing through the cleft lip. To blow over an octave, the air speed has to be roughly doubled. The approach is just as important, but often overestimated in its tension and the importance of the speed of air. The blower describes the approach as the position of the lips against the air and the balance between lip gap size and muscle tension. The lip gap must always be kept open against the air flow. So that the lips can swing freely, the lip gap must not be pressed shut and the mouthpiece must not be pressed on (pressureless or weak pressure blowing). In return, the lip tension has to be just high enough to withstand the energy of the air flow without additional pressure on the mouthpiece. In this way, the lips can swing freely without hindering each other due to the pressing force of the mouthpiece or contact (background noise, unnecessarily high resistance).

The duration of a tone to be sustained is also dependent on the one hand on the lung volume of the blower and on the other hand on the efficiency of his blowing technique. The optimum is achieved when the energy transported by the air flow causes the lips to vibrate with as little tension as possible, but with as much tense lip muscles as necessary to achieve the pitch and dynamics. If the wind player reaches the optimum, he needs less air to excite the oscillation and can keep the tone longer depending on the volume dynamics (music) : Tones of up to approx. 60 seconds are possible at low volume (with circular breathing, any longer).

The more relaxed the lip muscles work in the lower and middle areas, the more room the blower has upwards. If it is possible to make the lips vibrate through more relaxation with little energy, the blower can achieve higher tones with sufficient acceleration of the air ( efficiency ). If the lip tension is too high and the opening too small, the resistance at the lip gap increases accordingly. As a result, more air (energy) is required for the sound generation and the sounds respond more difficult or not at all.

In order to blow the sound beautifully, it should always start initialized from the air, not by an external impulse, e.g. B. the tongue thrust . The time-coordinated shock only specifies the beginning of the lip oscillation. It does not represent a valve in the sense of a closure.

### Influence of the bell

An important deviation from the simple conical tube is given by the bell or bell. This instrument typical Exponentialtrichter transforms the characteristic impedance of the very high value of the tube to significantly lower characteristic acoustic impedance of the air, thereby causing more effective radiation of sound - energy into the environment. Only the rest of the energy is reflected back into the pipe to generate the standing wave. The funnel affects the timbre , but also the interval between the natural tones, because the gradual change in cross-section creates the effect of the variable acoustic pipe length: the point of reflection outside the funnel can be shifted slightly with the aid of the flow velocity of the air and the approach . This phenomenon has not yet been adequately researched; have an influence z. B. also the shape of the inside of the mouth of the fan and the position of the tongue.

Instruments with a slightly open, flat funnel are the bow horns . They respond very easily, but sound relatively quiet and soft because their overtone content is low. The pitch can be varied well by the wind player with the approach (+ 10 / -50 cents ), because the flat funnel represents an imprecise separation edge for the reflection. The funnel gives off relatively little sound energy to the ambient air; this reflects more energy into the instrument so that the standing wave is easily formed.

Steeper funnels have trumpet or trombone , which are relatively difficult to respond, but have a tone rich in overtones, light to sharp, which is more difficult to intonate . The pitch can only be shifted slightly using the blowing technique, so intonation corrections are only possible to a very limited extent. Steep funnels emit more sound energy, so the instruments sound relatively louder . At the same time, this reduces the reflected energy for the formation of the standing wave.

### Influence of the scale length

The bowl or funnel mouthpiece is in a mostly conical mouthpipe. The following cylindrical tubes, where the valve bends are also located, define the "bore". Sometimes this is followed by a conical “push” before the instrument ends in the bell with the bell. The lengths and diameters of these individual segments determine the overall length of the respective brass instrument. This term describes the slope of the pipe diameter to the respective position in the basic pipe length. It is therefore not possible to define an exact metric measure, rather one usually compares instruments of the same length.

On the one hand, the length of the scale determines the timbre of the instrument: a trombone sounds brighter than a baritone horn , a trumpet brighter than a flugelhorn . With the trumpet, up to 40 partial overtones can be detected and displayed with the oscilloscope . Their share as well as their strength in this spectrum determine the timbre of the instrument and its deviations with the same design. On the other hand, the scale length influences how well the 1st natural tone (the "basic tone") responds. With French horns, the lowest “reliably” playable tone in the natural tone series is only the second natural tone, an octave above the actual fundamental. Due to the comparatively very narrow scale length of the French horn, as well as the small scale length and bore of the funnel-shaped horn mouthpiece (its edge diameter is comparable to the tulip-shaped cup of the trumpet mouthpiece), the keynote (F 1 = 46 Hz) can only be blown with extraordinary looseness, while the same tone with the same tube length is the normal case on the F tuba. Apart from this problem, experienced wind players can blow the fundamental notes with pure intonation on all brass instruments.

Furthermore, the scale has an influence on the exact interval between the natural tones. Specific natural tones can be changed in their intonation by selective changes in diameter. The clean intonation of the natural tone row is an essential quality feature.

The scale length has no influence on the pitch of the fundamental. This is determined exclusively by the length of the air column .

## Scale types

Different types of scale: 1 wide, 2 narrow
• Narrow gauge - the leadpipe is slightly conical ( natural trumpet ) or cylindrical (some trombones ), approx. 60% of the total length is cylindrical, the bell is wide open.
• Mittelmensuriert - The lead pipe and the bell are long and strong conical, cylindrical shares for relatively short. B. As with the flugelhorn or French horn approx. 30% of the total length, the bell is wide.
• Wide-scaled - the scale length is, apart from a few parts, strongly conical throughout, the bell jar not very protruding. z. E.g .: tenor horn , baritone , tuba

## Pitch control

Change of the resonance pipe length:

In order to enable a chromatic way of playing, brass instruments were equipped with the option of extending the length of the tube with a slide (telescopic tube) (slide trumpet, trombone ) as early as the 14th century . This opened up further proportionally shifted series of natural tones. The opposite of this is formed by the instruments with tone holes or keys ( flap horn , ophikleide ) that were created afterwards , in which the air column is shortened accordingly.

The most important innovation, however, is the invention of valve instruments around 1813 by Friedrich Blühmel and Heinrich Stölzel , which have since formed the vast majority of all common brass instruments .

Soon afterwards the classic configuration with three valves prevailed, which lower the fundamental tone by two, one and three semitones . With such a three-valve instrument it is possible to play a continuous chromatic scale from a fifth above the root note.

If there is another valve, it is usually a fourth valve (five semitones). Historically, for reasons of intonation , some instruments were also built with five, six or more valves, a practice that has been preserved with the tuba to this day . (Further information can be found under Valve (wind instrument) and the articles on the respective instrument itself.)

Nowadays, trombones are mainly played with one slide (sometimes supplemented by one or two valves ). Key instruments are mostly only used in the sense of historical performance practice .

To help with voicing poorly tuned tones, especially when combining several valves, the valve extension slide (sometimes also the main tuning slide) is designed to be extendable and thus changeable during the blowing with the help of a device or in the form of a so-called trigger.

## history

Dungchen , a natural trumpet used by Tibetan monks, 1938

### Antiquity

When the tomb of Pharaoh Tutankhamun from 1323 BC Was discovered, two specimens of the oldest brass instrument still in existence today, the Scheneb, were found . These trumpet-like instruments are approx. 58 cm long, have a diameter of 17 mm (blowing side) to 26 mm and an adjoining bell with up to 88 mm. Both instruments are made of hammered and soldered sheet metal: one made of partially gold-plated silver, the other made of a copper alloy. Nothing has been handed down in writing about blowing techniques and their specific use, but pictorial representations (probably as early as around 2300 BC) place them in a military or representative context.

Another instrument from this culture is the Jewish chazozra . In the context of the Old Testament ( Tanach ), God asked Moses after leaving Egypt ( 4 Mos 10.2  EU ) to make two trumpets out of chased silver. Associated with this is a relatively detailed regulation on application at the same point. Religious use was incumbent on the Levites in the Jerusalem temple . However, these trumpets are also purely signal instruments and are neither made nor suitable for making music. Original instruments have probably not survived, the last ones likely fell victim to the sack of the temple, as shown in the image in the Arch of Titus .

Scheneb and the Chazozra consisted of forged and soldered sheet metal. At the same time, the art of the lost wax process was already known from the 4th millennium BC. Several instruments were created like this:

• Parts of the Greek Salpinx were made like this: an elongated trumpet with a mouthpiece and bell made of bronze and 13 ivory spacers. A preserved instrument (157 cm long) from approx. 450 BC. BC is in the Museum of Fine Arts, Boston .

The Romans took over from around 300 BC. From the culture of the Etruscans there were also various brass instruments made of cast bronze with removable mouthpieces.

• The tuba is an elongated, continuously conical instrument, a preserved example in the Etruscan Museum ( Villa Giulia ) in Rome is 117 cm long and had a slightly projecting bell.
• The G-shaped cornu was a long instrument curved around the body of the wind player. The bucina was shaped similarly .
• The hook shape of the Roman Lituus and the Celtic Karnyx probably originated from the connection of a straight pipe with a crooked animal horn as a bell.
• The pairs used lur of the Germans, which were composed of a plurality of bent parts, required a high degree of manual skill in the cast bronze and bronze forging. The shape of the lurs was probably based on how they were handled.

### Middle Ages and Modern Times

#### Trumpets and trombones

It is not clear whether the art of bending thin-walled tubes was passed down from antiquity through the Middle Ages or had to be rediscovered in the West. Early medieval instruments were elongated, the earliest illustration of an S-shaped sinuous form can be seen on a miniature from 1377 (Cronicles of France) in the British Library .

From around 1500 onwards, the single-wound long trumpet emerged as the standard form , which as a baroque trumpet remained practically unchanged until the end of the 18th century. Since only series of natural tones are possible on fixed tubes and playing clarino in the high register became unusual, the desire for playable tones between the (lower) natural tones arose. The plug was only limited practical for trumpets. The constant switching between instruments with different moods was no improvement either. A first step was to change the pipe length by attaching pipe sections (set pieces). In order to generate semitone steps in rapid succession, a telescopically extendable leadpipe was probably used on the instruments (tromba da tirarsi) (painting by Hans Memling , approx. 1480).

The development of the pull-out double slide and thus the actual trombone probably took place in Burgundy (southern France) in the middle of the 15th century. At the same time, thin-walled instruments were created with the essential feature of today's French horn, the circularly curved tube. There are images of such "horns" on images in Worcester or in Terlan in Tyrol.

In today's symphony orchestras , the brass instruments are usually arranged in the middle at the back.

#### Finger holes and valves

From the family of tines , which was widespread in the Renaissance and, according to today's terminology, belongs to the brass instruments, further forms of finger hole horns developed. The pitch change in the grip hole horn is analogous to a woodwind : assault holes or flaps achieved the wind shortening the vibrating air column. By the standards of the 19th century, however, the sound character of the tones produced was not as satisfactory as that of a natural tone. Nevertheless, the Serpent , Basshorn and the more modern Ophikleide lasted well into the 19th century. With the ophicleide and the tuba , instruments were developed that could also be played chromatically in the bass range. The key horn and key trumpet came from the Italian region and were popular instruments for a long time.

The invention of valves in the 1810s changed the importance of brass instruments and their place in music. The opera Rienzi by Richard Wagner (UA 1842 in Dresden) already used valve trumpets, along the lines of Cornet à pistons in the French opera. The chromatically playable cornet, often called the “post horn” in German-speaking areas, has become a popular solo instrument.

### Half instrument / full instrument

Karl Emil von Schafhäutl reported about half-instruments in 1854 in a report from an industrial exhibition in Munich:

“Tight lengths favor the high [notes], widen the low. So speaks z. B. the fundamental tone [pedal tone or first natural tone] on trumpets and cornets not, but on tubas . […] In addition, the upper and lower limits are determined by the ability of the wind player and the shape of the mouthpiece . "

Than half instrument he described thus 20 years after the invention of the valves a engmensuriertes brass instrument, wherein the pedal tone (or first natural clay) poorly responsive, not playable and thus normally is not usable. In contrast, there are full instruments in which the pedal tone can be used well. The terms half-instrument / full- instrument have no longer been relevant in terms of instrument making since around 1900; in the early years of brass instrument development they were probably only cited advertising attributes .

The phenomenon of the extremely poorly tuning (ie “missing”) keynote is based on the physical properties of the instrument shape. A strongly conical shape of the main tube, i.e. a wide scale length, supports the desired frequency ratio of 1: 2 ( octave ) of the first two natural tones, while a largely cylindrical scale length (constant tube without bell ) shifts this ratio to about 1: 2.5. The desired tone is five semitones too deep, but can still be generated (albeit difficult).

## Basic mood

In practice with brass instruments, this term denotes the note name of the (1st,) 2nd, 4th, 8th etc. natural tone , regardless of its absolute octave . For example, if a Bb trumpet and a Bb tenor horn blow the 3rd natural note, both instruments will sound octave apart. The overall sound is generally perceived as pleasant. For example, if a Bb trumpet and a C trumpet blow the 2nd natural note , both instruments will sound within seconds . The overall sound is generally perceived as unpleasant.

The basic tuning is determined by the length of the basic pipe

• with trumpets: The train is fully inserted.
• For valve instruments: No valve is actuated.

The fundamental pitch f in Hertz is physically dependent on the instrument tube length l in meters and the speed of sound c of the air .

With the formula: the length or, conversely, the frequency can be calculated. ${\ displaystyle \ mathrm {l} = {\ tfrac {c} {2f}}}$

All instruments with the same keynote therefore have roughly the same tube length. For example, the tube lengths of the French horn in Bb (274 cm), the trombone (270 cm), the tenor horn (266 cm) and the baritone horn or euphonium in B (262 cm) are almost the same. At 370 cm, the French horn in F is slightly longer than the tuba in F (354 cm). These differences in length within the same basic tuning depend on the construction of the instrument, in particular on the scale length and the opening angle and diameter of the bell.

The shortest brass instrument in use is the Bb piccolo trumpet with a base tube length of 65 cm. The Bb tuba with four valves is usually the deepest instrument with a basic tube length of 541 cm. If the extensions of normally four valves are added, the tube length is 930 cm.

In a normal, separate F / Bb double horn , 704 cm of tube are built in, and an additional 96 cm is added to the Bb horn when switching to F tuning. In order to be able to correct intonation, the F-valve slides (total length 102 cm) are used independently of the B-valve slides.

## Individual parts and assemblies

Colloquially, modern brass instruments have mostly the same assemblies regardless of their size:

Individual parts of a French horn: 1 leadpipe; 2 vocal slurs; 3 kickoff; 4 clamp; 5 stems; 6 screw connection; 7 bell; 8 machine; 9 valve bends; 10 finger hooks

### Tuning slide

The tuning slide influences the overall length of the instrument and consists of two parallel telescopic tubes, connected by an arch. That is why the term tuning bow is also used . If you pull the vocal arc further out, i.e. if you lengthen the total length of the instrument, the notes become deeper. If you push the vocal arc further in, the notes become higher.

### Water key

One or more water keys (if available) can be used to quickly remove the condensation from the instrument during breaks during music-making. The position of the water key (s) is selected so that they are in the blowing position at the lowest point of a pipe.

## production

Brass instruments are usually made of brass sheet and tubing with a wall thickness of 0.4 to 0.6 mm. Bells and large conical tubes are soldered together from sheet metal with silver-containing hard solder and pressed into the desired shape with the appropriate tools . Cylindrical tubes are seamlessly manufactured industrially. The individual possibly bent pipe parts are soldered with short pipe pieces (“clamps”) overlapping with soft solder.

Traditionally, pipes to be bent by a brass instrument maker are filled with liquid lead and then bent "by hand" after cooling. The surface is smoothed, compacted and hardened using special techniques. The lead is then liquefied and completely removed. This bending process can also be carried out using metals with a low melting point or liquefiable synthetic resins.

In modern industrial mass production, the bell is deep-drawn from a round blank and brazed flush with the corresponding conical stem. Pipes are often bent with a water ice filling, then they are smoothed hydraulically in a divisible matrix shape . In terms of manufacturing technology, this requires greater material thicknesses (up to 1 mm), the durability of finished instruments is sometimes extremely short: Through extreme "inflation", homogeneous crystal structures tear apart and develop capillary cracks through which condensation water inevitably diffuses in a finished instrument . Lacquered surfaces prevent evaporation, irreversible damage to the instrument occurs.

Finished individual parts are often ground and polished before they are assembled . The finished instrument can then be painted or galvanically silver-plated , nickel-plated or gold-plated .

## Instruments

A valve horn around 1900

## Manufacturers and brands

Like most musical instruments, brass instruments are not only manufactured by large companies, but also by small, highly specialized, specialist companies that sometimes only consist of a single master brass instrument maker .

## literature

• Heinz Bahnert, Theodor Herzberg, Herbert Schramm: Brass instruments. Fachbuchverlag Leipzig / Florian Noetzel Verlag, Wilhelmshaven 1986, ISBN 3-7959-0466-8 .
• Anthony Baines: Brass Instruments: Their History and Development. (Dover Books on Music) Dover Publications, Mineola (New York) 2012, ISBN 978-0486275741 .
• Günter Dullat: Metalwind instrument making . PPV Medien GmbH. ISBN 3-923639-79-1 .
• Herbert Heyde: The valve wind instrument. VEB DVfM 1987, ISBN 3-370-00159-4 .
• Conny Restle and Christian Breternitz: Valve.Brass.Music. 200 years of valve wind instruments. (Exhibition catalog) Nicolaische Verlagsbuchhandlung, Berlin 2013, ISBN 978-3-89479-836-9 .
• Curt Sachs : Handbook of Musical Instruments. Breitkopf & Härtel, Leipzig 1930, reprint 1967, 1980
• Willy Schneider: Handbook of brass music . B. Schott's Sons, Mainz 1954