4.6 Radiation of Sound from Brass Instruments
189
Fig. 4.80 Schlieren optical apparatus for high-speed imaging of shock waves from a brass
instrument (López-Carromero et al. 2016)
Fig. 4.81 Four successive schlieren images of a shock wave radiated from the bell of a natural
trumpet driven by an electroacoustic transducer at the mouthpiece (López-Carromero et al. 2016)
The shock wavefronts are approximately circular arcs, and with appropriate
processing, it is possible to fit circles to a set of expanding wavefronts in front of
the bell (López-Carromero 2018). Figure 4.82 illustrates the fitted circles for two
different shapes of bell profile. In Fig. 4.82a the ‘bell’ is a conical glass funnel. In
this case the circles have a common centre very close to the apparent apex of the
189
Fig. 4.80 Schlieren optical apparatus for high-speed imaging of shock waves from a brass
instrument (López-Carromero et al. 2016)
Fig. 4.81 Four successive schlieren images of a shock wave radiated from the bell of a natural
trumpet driven by an electroacoustic transducer at the mouthpiece (López-Carromero et al. 2016)
The shock wavefronts are approximately circular arcs, and with appropriate
processing, it is possible to fit circles to a set of expanding wavefronts in front of
the bell (López-Carromero 2018). Figure 4.82 illustrates the fitted circles for two
different shapes of bell profile. In Fig. 4.82a the ‘bell’ is a conical glass funnel. In
this case the circles have a common centre very close to the apparent apex of the