Abstract: A mechanically amplified electroacoustic transducer system comprising an electroacoustic transducer having a vibrating element and an amplifier rod forming a probe extending from the transducer and in acoustically coupling contact with the vibrating element over a relatively small region thereof. The probe has a length which is approximately equal to the quarter wavelength or a multiple of the quarter wavelength of the acoustical energy generated by the transducer, the exact length of the probe being selected to provide optimum output from the system at a selected operation frequency of the transducer.

Abstract: Methods are described for rapidly damping oscillation of an acoustically levitated object or for causing and maintaining such oscillations, and a method is provided for determining the restoring force constant K on the levitated object by measuring its frequency of oscillation. Oscillations of a levitated object are damped by applying levitating acoustic energy at a frequency slightly less than the center resonant frequency. Oscillations are maintained by applying acoustic energy slightly greater than the center resonant frequency. The restoring force constant of the levitation force is proportional to square of the frequency of oscillation of the object.