Damping of an electrodynamic loudspeaker has been studied with respect to air turbulence and viscosity. Both quantities were evaluated as a difference of damping friction measured in air and in an evacuated space. The viscous friction dominates for small driving currents (< 10 mA) and is masked by turbulence for currents extending up to 100 mA. Turbulence contribution was evaluated as a difference of air damping friction recorded at 1.0 and 0.1 bars, and it was studied for selected driving frequencies. Hot wire anemometry has been adopted to meet requirements of convection study from the loudspeaker, and obtained spectra were compared to measured turbulence friction, in order to trace the perturbation of emitted signal by turbulent motion.
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