A method is described that allows the ultrasonic absorption coefficient U of liquids to be precisely measured between about 1 and 100 MHz. The automatic measuring procedure can be performed easily and comparatively fast. At high a values t h e accuracy of the method is clearly superior to the more time-consuming resonator technique, which is applied in this frequency range. This accuracy is achieved by careful construction and adjustment of the specimen cell, by semiempirical consideration of diffraction effects within the sample, and by precise calibration of the set-up by a specially designed below cut-off piston attenuator. The short measuring time is enabled by the particular mode of operation also described in this paper.

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