Les variations de la conduction osseuse en fonction de la force de pression exercée sur le vibrateur

The intensity change of sound produced by pressing a tuning-fork or a bone-conduction receiver against the head is a well known phenomenon. After having presented a review of the criticism made by otologists and audiologists, the theory of the mechanism of bone conduction and the results of measurements published by different authors have been summarised in this paper. Finally, the effects of the varying force with which the knob of the vibrator is pressed against the forehead are reported for three well-known types of bone-conduction receivers. According to the receivers and to the frequency, varying the force of application by as much as 250 to 1500 g may cause a change of 15 or 20 dB in the determination of bone-conduction acuity.