result sound energy lingering in the area, increasing the duration of the paddle impact event thus increasing the sound exposure. 4.2 Frequency Band Analysis The spectral distribution of the sound created by the paddle impacts can affect the perception of the sound quality. Figure 4.1 compares the octave band sound pressure levels of the four balls based on the average of a number of spectra. Each curve has been normalized to 0 dBA. Although each curve has the same overall A-weighted level there is a large difference in the 1,000 Hz band. The Foam Quiet ball spreads energy across many octave bands while the other balls have a maximum in the 1,000 Hz band. The latter balls have a distinct ping sound while the Foam Quiet ball produces more of a thud. The reason for this appears to be that the compliance of the foam ball creates a longer contact period with the paddle and is not able to excite the higher frequency paddle resonance near 1,000 Hz that radiates sound more efficiently. It is interesting that the Dura and Onix balls produce similar spectra, but the Dura is slightly louder.
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Foam Quiet Monarch Onix Dura 40
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Figure 4.1. Unweighted Frequency Band Sound Pressure Levels Normalized to 0 dBA
4.3 Pickleball Courts Directivity Pickleball paddles are known to have a roughly dipole radiation pattern, i.e. a figure eight
27 of 58 Spendiarian & Willis Acoustics & Noise Control LLC
12/15/2019
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