1.2 The Musician’s Interpretation of the Brass Playing Experience
15
Musical experience confirms that the easily sounded notes on a well-made
brass instrument usually correspond closely in pitch to members of a harmonic
series, whose fundamental pitch is basically determined by the tube length of
the instrument. However the pitches of the playable notes are strongly influenced
by the resonance frequencies of the instrument’s air column, and we will see in
Sect. 4.3 that in realistic brass instruments, these resonance frequencies are never
exact members of a harmonic series. For that reason we will avoid using the term
‘harmonic’ to describe one of the easily playable notes on a brass instrument,
employing instead the more neutral term ‘natural note’.
The natural notes are not absolutely fixed, but can be raised or lowered in pitch to
some extent by changing the breath pressure and/or lip muscle tension. The degree
to which the natural notes can be moved varies from one instrument to another and
from one dynamic to another: the pitch of loud notes on a trombone can be varied
very little, while moderately quiet notes on the serpent can be moved through several
semitones. Players often think in terms of a ‘pitch centre’, meaning the pitch of a
natural note at which the response of the instrument is easiest and sound is produced
most efficiently. Musicians use the term ‘slotting’ to indicate the experience in
which feedback from a brass instrument pulls the player’s lip vibrations up or down
in frequency until the vibration falls into a ‘slot’ at the pitch centre of the note (see
Sect. 2.2.2).
1.2.3 Nominal Pitches of Brass Instruments
The pitches of the natural notes available on a brass instrument are commonly
indicated by attaching a pitch letter to the instrument name. In the Symphony No.
5 in C minor by Beethoven, for example, the score includes parts for two trumpets
described as ‘trombe in C’ (Fig. 1.13a). The trumpets for which Beethoven was
writing in the early years of the nineteenth century were valveless instruments
capable of playing only the natural notes of the fixed length tube. A comparison
of the pitches in Fig. 1.13a with the pitches shown in Fig. 1.12 confirms that
Beethoven’s trumpet in C was an instrument with a total tube length of around 2.4 m,
with natural notes close to a harmonic series with fundamental pitch C2.
The score of Bartók’s Concerto for Orchestra also includes parts for ‘trumpets in
C’. The twentieth-century trumpets scored for by Bartók were very different from
the instruments familiar to Beethoven: they were valved trumpets capable of fully
chromatic playing, as the excerpt reproduced in Fig. 1.13b shows. The tube length
of the twentieth-century trumpet in C was around 1.2 m, only half that of the early
nineteenth-century natural trumpet, and its natural notes corresponded to a harmonic
series with fundamental pitch C3.
To distinguish between different instruments with the same pitch letter but
different lengths, it is possible to extend the nomenclature to include a reference
to the octave of the nominal fundamental. Using this system, the Beethoven trumpet
is described as a ‘trumpet with nominal fundamental C2’, while the Bartók trumpet
15
Musical experience confirms that the easily sounded notes on a well-made
brass instrument usually correspond closely in pitch to members of a harmonic
series, whose fundamental pitch is basically determined by the tube length of
the instrument. However the pitches of the playable notes are strongly influenced
by the resonance frequencies of the instrument’s air column, and we will see in
Sect. 4.3 that in realistic brass instruments, these resonance frequencies are never
exact members of a harmonic series. For that reason we will avoid using the term
‘harmonic’ to describe one of the easily playable notes on a brass instrument,
employing instead the more neutral term ‘natural note’.
The natural notes are not absolutely fixed, but can be raised or lowered in pitch to
some extent by changing the breath pressure and/or lip muscle tension. The degree
to which the natural notes can be moved varies from one instrument to another and
from one dynamic to another: the pitch of loud notes on a trombone can be varied
very little, while moderately quiet notes on the serpent can be moved through several
semitones. Players often think in terms of a ‘pitch centre’, meaning the pitch of a
natural note at which the response of the instrument is easiest and sound is produced
most efficiently. Musicians use the term ‘slotting’ to indicate the experience in
which feedback from a brass instrument pulls the player’s lip vibrations up or down
in frequency until the vibration falls into a ‘slot’ at the pitch centre of the note (see
Sect. 2.2.2).
1.2.3 Nominal Pitches of Brass Instruments
The pitches of the natural notes available on a brass instrument are commonly
indicated by attaching a pitch letter to the instrument name. In the Symphony No.
5 in C minor by Beethoven, for example, the score includes parts for two trumpets
described as ‘trombe in C’ (Fig. 1.13a). The trumpets for which Beethoven was
writing in the early years of the nineteenth century were valveless instruments
capable of playing only the natural notes of the fixed length tube. A comparison
of the pitches in Fig. 1.13a with the pitches shown in Fig. 1.12 confirms that
Beethoven’s trumpet in C was an instrument with a total tube length of around 2.4 m,
with natural notes close to a harmonic series with fundamental pitch C2.
The score of Bartók’s Concerto for Orchestra also includes parts for ‘trumpets in
C’. The twentieth-century trumpets scored for by Bartók were very different from
the instruments familiar to Beethoven: they were valved trumpets capable of fully
chromatic playing, as the excerpt reproduced in Fig. 1.13b shows. The tube length
of the twentieth-century trumpet in C was around 1.2 m, only half that of the early
nineteenth-century natural trumpet, and its natural notes corresponded to a harmonic
series with fundamental pitch C3.
To distinguish between different instruments with the same pitch letter but
different lengths, it is possible to extend the nomenclature to include a reference
to the octave of the nominal fundamental. Using this system, the Beethoven trumpet
is described as a ‘trumpet with nominal fundamental C2’, while the Bartók trumpet