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Results

Three basic types of results were recorded: results with no oscillation, indicating that a resonance mode was not excited, periodic oscillations, indicating that a resonance mode was excited, and strange aperiodic oscillations or oscillations with unexpected tone, that indicate either strange parameter combinations or issues with the model.

The results of the first set of mode excitation tests are summarized in Table 2. Each set of parameters is used to generate a three-second simulation. When oscillation is produced, the value of ξequily for which the amplitude is maximized is indicated, as well as observations of the audio produced.

flip (Hz) pmax (Pa) ξequily for maximum amplitude (m) Observations of sound produced Audio example
60 2000 0.002 Sounds like a pedal oscillation
100 2000 No oscillation N/A N/A
100 2500 0.002 A bit lower than the first resonant mode of the trumpet.
150 2500 No oscillation N/A N/A
200 2500 No oscillation N/A N/A
250 2500 -0.0001 Sounds like a middle C
300 2500 0.002 Sounds like a D4
300 3000 0.002 Sounds like a D4
350 3000 0.002 Sounds like an F, the third resonance mode of the B flat trumpet
400 3000 0.002 Really weird high-frequency component to the sound
400 3000 0.0012 Steady oscillation around a G4
450 3500 No oscillation N/A N/A
500 3500 No oscillation N/A N/A
500 4000 No oscillation N/A N/A
550 4000 No oscillation N/A N/A
600 4000 No oscillation N/A N/A
600 5000 No oscillation N/A N/A
650 5000 No oscillation N/A N/A
700 5000 No oscillation N/A N/A
Table 2: results from testing flip values from 60 - 1700 Hz

As shown in Table 2, most of the lip frequency and blowing pressure did not excite an oscillation for any of the ξequily values tested. Only three of the six resonance modes that Adachi and Sato report having excited were excited in these trials, and some tones were excited that do not correspond to resonance peaks. There were also some tones produced that had unexpected timbres.

To attempt to excite the specific resonance modes, the peaks in the impedance were selected using a peak detection algorithm, and used directly as the flip values, along with the blowing pressure values given in Adachi and Sato (1996). The results of this method are in Table 3 below.

Resonance mode Impedance peak frequency/flip (Hz) pmax (Pa) ξequily for maximum amplitude (m) Sounding frequency from FFT (Hz) Observations of sound produced Audio example
I 86 2000 0.002 87.667 No oscillation for the first two seconds; oscillation of a pedal tone begins around the last second.
II 234.6 2500 -0.0001 237.33 Sounds around a B flat3, the second resonance mode, but the tone decays almost like a struck instrument instead of sustaining until the end of the simulation.
III 352 3000 0.002 350 Periodic oscillation around an F4, the third resonance mode.
IV 471.2 3500 No periodic oscillation. N/A N/A N/A
V 593.6 4000 No periodic oscillation. N/A N/A N/A
VI 714.4 5000 No periodic oscillation. N/A N/A N/A
Table 3: results from testing flip values equal to resonance frequencies

Once again, the higher resonance modes are not excited at all, so that only the first three of six resonance modes produce oscillations.