A Pulse-Tone Technique for Clinical Audiometric Threshold Measurements

The pulse-tone method of testing hearing, used as a basis for the 1939–40 World's Fair tests in which over one million individuals voluntarily participated, has been adapted for clinical audiometric use. For this purpose, a tri-functional control has been utilized consisting of (1) an electronic method of producing the desired number of tone pulses (normally one, two, three, or four) in a selected sequence under control of the operator, (2) a visual signal which occurs at the beginning of each pulse series to act as a warning to the observer, and (3), a visual signal which flashes in synchronism with the output tone pulses to act as a counter for the operator. In threshold tests in which both the pulse-tone method and the standard audiometric method were used, approximately three out of every four operators and a similar percentage of observers expressed a preference for the pulse-tone procedure. For the very young listener, the pulse-tone test appears to be preferable in the majority of cases. The normal threshold intensity calibrations of the two tests are in good agreement so that either test may be used interchangeably with the other. The time required to make a pulse-tone audiogram is slightly in excess of that required to make a measurement by the standard procedure, but the resulting data are more reproducible.