Deafness, Sound pressure-Measurement, MP3 players, Hearing loss, Data acquisition system, Spin, Microcontroller, Analog to digital converter, Data storage, Microphone, Signal processing
Listening to loud music for extended periods of time has been shown to lead to long-term hearing loss. To date, much of the research regarding the impact on hearing of listening to music with ear buds has been survey based. This work focuses on the development of a system for the collection, storage and analysis of sound pressure output measurements. Currently, there is a need for quantitative data to establish the impact of music listening on hearing loss by measurements of sound pressure levels in the ear canal. The study described here designs, develops and implements a headphone system via a microphone communicating with a microcontroller that is capable of making physical measurements of the factors involved in damaging the hearing mechanism. A data acquisition system was designed, built and tested. The development of the prototype included building the necessary circuitry of the hardware and writing the accompanying software application. The hardware component included a Parallax microcontroller, an analog to digital converter, a microphone, and a card adapter for a microSD card. The application was developed using the Spin programming language. The analog to digital converter acquired data at a sampling rate of 24 kHz, by running the application either as a single core process, or as a multicore process. The prototype collects continuous data for a maximum of 0.4 s, and it requires 5.7 s to store and write the data on a microSD card. The functionality of the data acquisition system was validated by analyzing the output of analog sinusoidal input signals of four frequencies (100 Hz, 1 kHz, 2.4 kHz, and 4 kHz) with di erent amplitudes (200 mV, 400 mV, 800 mV, and 1 V). The response of the developed prototype con rmed the expected behaviour of the input signal for all parameters tested. A music application was used to assess the ability of the data acquisition system to collect data over an inde nite period of time, taking into account the duration allocated for storing data. Thesis Supervisor: S
Draghici, Adina-Elena, "Design of a portable data acquisition system to measure real-time MP3-player sound pressure output" (2012). Theses, Dissertations, and Projects. 92.