Air velocity was recorded in front of an electrodynamic loudspeaker by the use of hot wire anemometric technique. Wire temperature response was detected up to 2 kHz and harmonics were analyzed by the use of the King formula. Near field effects were detected at the z-axis distances comparable to the loudspeaker diameter. Extended Greenspan theory was applied to explain measured data. It was stressed the importance of air viscosity in damping of Morse convection in near field regime. Near field effects at distances up to 30 cm were discussed in terms of the Morse convection indicated by the imaginary part of air impedance. According to continuity equation of air flow microphone signal was correlated to the fluid velocity divergence.
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