4.6 Radiation of Sound from Brass Instruments
179
Fig. 4.75 The player’s hand inserted into the bell of a french horn. (a) Normal position; (b)
stopped position. Courtesy of Lisa Norman
lowers the pitch of every natural note. Changes in hand position enable ‘out-ofseries’ notes to be played and are used to control the intonation and timbre of the
radiated sound. The basic acoustics of this hand technique is similar to that of the
internal mutes described earlier in Sect. 4.5. The insertion of the hand increases
the reflection of sound energy, extending the frequency range over which significant
impedance peaks are available to support note production (Benade 1973; Yoshikawa
and Nobara 2017).
When the hand of the player almost completely closes the bell (Fig. 4.75b), a
series of ‘stopped’ notes can be sounded. On a horn whose nominal fundamental
pitch is 12 ft F (Sect. 7.2.7), the stopped notes are a semitone above the natural
notes of the unstopped horn. The player’s hand is then performing the same role as
the transposing baroque trumpet mute, lowering the frequencies of all the natural
notes to such an extent that a new harmonic series can be found by reassigning the
peak numbers to a higher nominal fundamental frequency (Campbell and Greated
1987).
On shorter horns with nominal fundamental pitch higher than 11 ft G, the stopped
notes lie more than a semitone above the unstopped notes, and cannot therefore
be used to supply in tune accidentals. The B side of a double horn often has an
additional ‘stopping valve’, which allows the stopped notes to be played in tune
without adjusting the main tuning slide.
4.6 Radiation of Sound from Brass Instruments
The previous sections of this chapter have been mainly concerned with the nature of
the sound waves in the air inside the tubing of brass instruments. The behaviour of
sound waves reaching the end of a flaring bell was discussed in Sect. 4.3.8, but the
focus there was on the way in which the change in cross-section in the bell region
influenced the standing waves set up in the air column of the instrument. The bell
179
Fig. 4.75 The player’s hand inserted into the bell of a french horn. (a) Normal position; (b)
stopped position. Courtesy of Lisa Norman
lowers the pitch of every natural note. Changes in hand position enable ‘out-ofseries’ notes to be played and are used to control the intonation and timbre of the
radiated sound. The basic acoustics of this hand technique is similar to that of the
internal mutes described earlier in Sect. 4.5. The insertion of the hand increases
the reflection of sound energy, extending the frequency range over which significant
impedance peaks are available to support note production (Benade 1973; Yoshikawa
and Nobara 2017).
When the hand of the player almost completely closes the bell (Fig. 4.75b), a
series of ‘stopped’ notes can be sounded. On a horn whose nominal fundamental
pitch is 12 ft F (Sect. 7.2.7), the stopped notes are a semitone above the natural
notes of the unstopped horn. The player’s hand is then performing the same role as
the transposing baroque trumpet mute, lowering the frequencies of all the natural
notes to such an extent that a new harmonic series can be found by reassigning the
peak numbers to a higher nominal fundamental frequency (Campbell and Greated
1987).
On shorter horns with nominal fundamental pitch higher than 11 ft G, the stopped
notes lie more than a semitone above the unstopped notes, and cannot therefore
be used to supply in tune accidentals. The B side of a double horn often has an
additional ‘stopping valve’, which allows the stopped notes to be played in tune
without adjusting the main tuning slide.
4.6 Radiation of Sound from Brass Instruments
The previous sections of this chapter have been mainly concerned with the nature of
the sound waves in the air inside the tubing of brass instruments. The behaviour of
sound waves reaching the end of a flaring bell was discussed in Sect. 4.3.8, but the
focus there was on the way in which the change in cross-section in the bell region
influenced the standing waves set up in the air column of the instrument. The bell