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Updated: May 2, 2026

The Measurement of Unsteady Surface Pressure Using a Remote Microphone Probe
Published on: December 3, 2016
Sound pressure level generated by individual portable sound equipment
Izabella dos Santos1, Maria Francisca Colella-Santos2, Christiane Marques do Couto2
1Universidade Estadual de Campinas, CampinasSP, Brasil, Aprimoramento em Saúde Auditiva, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brasil.
Introduction:
The use of Personal Digital Audio Players can cause hearing injuries, as the sound is generated directly in the ear canal. It is believed that different types of headphones can cause different amplifications, since they cause changes in the volume and resonance of the ear canal according to their depth.
Objective:
This study aimed to determine the sound pressure to which young individuals are exposed when using Personal Digital Audio Players with two types of headphones: insertion earphones and anatomical insertion earphones.
Materials And Methods:
This was an experimental study. The probe microphone measurements were made with different headphones in 54 ears (27 young individuals). The resonance peaks were also recorded.
Results:
A statistically significant difference was observed between the evaluated headphones, showing that anatomical insertion earphones had higher levels of sound pressure than insertion earphones for all frequencies measured. There was no correlation between the resonance peak of the closed canal and the frequency where the highest sound pressure level was obtained. There was a significant difference between ears at some frequencies with the different headphones.
Conclusion:
It was concluded that anatomical insertion earphones generate a higher sound pressure level than insertion earphones.
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