392
8 How Brass Instruments Are Made
The composition of the brass is a matter of individual preference (see Sects. 1.3.3
and 6.6); typical proportions for instrument bells are around 70% copper, 30%
zinc (yellow brass); around 85% copper, 15% zinc (‘gold’ brass); and around
90% copper, 10% zinc (‘red’ brass). There are usually trace elements present in
commercially available brass, importantly a small amount of lead which is necessary
for turning in a lathe (von Steiger et al. 2013). The main parts of instruments are
fabricated from sheet brass and seamless tubing bought in from brass foundries.
Although brass continues to be regarded as the most commonly used material,
other metals have been used for brass instruments: bronze in the ancient world
(see Sect. 1.1.2), silver and in the nineteenth century the alloy german silver (also
known as white bronze, or Maillechort). The composition of german silver varies
but is typically around 70% copper, 18% nickel and 12% zinc. Today german silver
is more commonly used for garnishing such as ferrules, mouthpipe sheaths and bow
guards on instruments primarily of brass. So-called ‘beryllium’ bells have a small
percentage of beryllium added to copper or copper alloy.
Since the late twentieth century, the bells and larger sections of tubing of some
sousaphones have been made of fibreglass, principally to reduce the weight of
these instruments for marching band use. Carbon fibre, its strength superior to
that of brass, is proving to be a satisfactory material for components such as
bells and trombone outer slides for high-grade instruments. In recent years lowpriced plastic instruments have been developed which have proved commercially
successful: several firms offer trombones, trumpets and tubas. These instruments
are mostly made from acrylonitrile butadiene styrene (ABS), but some parts such as
slide stockings and valve components can be metal. There have been applications
of 3D printing to the production of instruments, both for rapid prototyping and
the production of replica instruments. Initial experiments have focussed on fingerhole brasswind such as cornetts and serpents which have been traditionally made of
wood.
8.2 Design
In Chap. 7 we saw how the overall bore profile determines in broad terms how
an instrument behaves. In Chaps. 4 and 6 we saw how details of the bore profile
such as the bell flare can influence compass, capability for intonation control,
dynamic range, timbre and responsiveness. With the understanding we now have of
brasswind acoustics, it is possible to design an instrument with some confidence in
predicting its behaviour in performance (Braden 2006). Nevertheless, the traditional
procedure of trial and error continues to guide instrument design. One reason for
this is that most new brass instruments brought to market are established kinds of
brasswind: it is very rare for a completely new type of instrument to be devised
in the way that Halari invented the ophicleide or Wieprecht and Moritz the bass
tuba in the nineteenth century. Tools are available such as the Brass Instrument
Analysis System (BIAS) (Artim 2020) with which makers can test instruments
8 How Brass Instruments Are Made
The composition of the brass is a matter of individual preference (see Sects. 1.3.3
and 6.6); typical proportions for instrument bells are around 70% copper, 30%
zinc (yellow brass); around 85% copper, 15% zinc (‘gold’ brass); and around
90% copper, 10% zinc (‘red’ brass). There are usually trace elements present in
commercially available brass, importantly a small amount of lead which is necessary
for turning in a lathe (von Steiger et al. 2013). The main parts of instruments are
fabricated from sheet brass and seamless tubing bought in from brass foundries.
Although brass continues to be regarded as the most commonly used material,
other metals have been used for brass instruments: bronze in the ancient world
(see Sect. 1.1.2), silver and in the nineteenth century the alloy german silver (also
known as white bronze, or Maillechort). The composition of german silver varies
but is typically around 70% copper, 18% nickel and 12% zinc. Today german silver
is more commonly used for garnishing such as ferrules, mouthpipe sheaths and bow
guards on instruments primarily of brass. So-called ‘beryllium’ bells have a small
percentage of beryllium added to copper or copper alloy.
Since the late twentieth century, the bells and larger sections of tubing of some
sousaphones have been made of fibreglass, principally to reduce the weight of
these instruments for marching band use. Carbon fibre, its strength superior to
that of brass, is proving to be a satisfactory material for components such as
bells and trombone outer slides for high-grade instruments. In recent years lowpriced plastic instruments have been developed which have proved commercially
successful: several firms offer trombones, trumpets and tubas. These instruments
are mostly made from acrylonitrile butadiene styrene (ABS), but some parts such as
slide stockings and valve components can be metal. There have been applications
of 3D printing to the production of instruments, both for rapid prototyping and
the production of replica instruments. Initial experiments have focussed on fingerhole brasswind such as cornetts and serpents which have been traditionally made of
wood.
8.2 Design
In Chap. 7 we saw how the overall bore profile determines in broad terms how
an instrument behaves. In Chaps. 4 and 6 we saw how details of the bore profile
such as the bell flare can influence compass, capability for intonation control,
dynamic range, timbre and responsiveness. With the understanding we now have of
brasswind acoustics, it is possible to design an instrument with some confidence in
predicting its behaviour in performance (Braden 2006). Nevertheless, the traditional
procedure of trial and error continues to guide instrument design. One reason for
this is that most new brass instruments brought to market are established kinds of
brasswind: it is very rare for a completely new type of instrument to be devised
in the way that Halari invented the ophicleide or Wieprecht and Moritz the bass
tuba in the nineteenth century. Tools are available such as the Brass Instrument
Analysis System (BIAS) (Artim 2020) with which makers can test instruments