Designing and Creating a Smart Audiometer Using …
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three-way button and then with the audio amplifier to make the test on the left ear or
right ear (Fig. 5).
After the electrical part has been started, the code is written to program the
audiometer, so that the LCD will display the current frequency and intensity, the
push buttons will be used to give PLAY the sound, and the second STOP” to stop
the test at the desired frequency and intensity. The potentiometer is programmed
to change the frequency or intensity by rotating it. The LM386 audio amplifier has
amplified your signal until it reaches the appropriate level to emit the sounds through
the headphones at the specified level. The microSD card reader module was used to
read the microSD card used as a flash memory, and the sounds were memorized.
Programming the microcontroller to perform automatic testing and wireless
module programming was the second major step in the source code because it gives
us the opportunity to escape the multitude of wires and cables and at the same time
gives us the opportunity to connect the audiometer to other devices or to connect
other peripheral components to the system. Thus, after the code was created in
the C++ program, it was stored on the Arduino MEGA 2560 development board.
An audiometer is capable of delivering tones between 125 and 16,000 Hz, the test
frequency being 125, 250, 500, 1000, 2000, 4000, 8000, 16,000 Hz, and the intensity
is amplified from 5 to 5 dB or 10 in 10 dB. In this sense, sounds were created using
the Fl Studio software (a virtual studio to create music), using a native instruments
massive synthesizer with three oscillators with over 40 wave forms, filters, stamp
modulator, frequency, etc (Fig. 6).
In this case, a single oscillator was used to generate the sinusoidal waveform,
since this is the basic form in acoustics, by the overlapping of the sinusoidal waves
the other signal forms are formed. During the tests, using a digital equalizer with a
visual panel, it has been found that the useful frequencies are somewhere between
Si (246.94 Hz B) and Do (261.63 Hz C), but closer to the Si basic frequency. In
this case, a single oscillator was used to generate the sinusoidal waveform, since this
is the basic form in acoustics, by the overlapping of the sinusoidal waves the other
signal forms are formed (Fig. 7).
The frequency was isolated using a more precise equalizer post using the “Peak
band” filter characteristic that is, leaving only the input frequency to pass. After the
desired frequency isolation, by removing the harmonics by leaving only the base
frequency to pass, pure tone was created, which was exported as a WAV audio file
at the 44.100 Hz sampling rate and 12-bit depth. To amplify the frequencies at the
required intensities (-10, 0, 10, 20 … 110 dB), Ozone 7 masked program from Izotop
was used. So, the audio files were loaded with the necessary frequencies, and the
equalizer was used to amplify or reduce the sound by 10 dB.
3 Results and Discussion
The audiometer features MP3 player-like features, where the sounds created in Fl
Studio are loaded onto a microSD card. With the card reader module, Arduino MEGA
2560 will play the sounds loaded on the card through the headphones each time we
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three-way button and then with the audio amplifier to make the test on the left ear or
right ear (Fig. 5).
After the electrical part has been started, the code is written to program the
audiometer, so that the LCD will display the current frequency and intensity, the
push buttons will be used to give PLAY the sound, and the second STOP” to stop
the test at the desired frequency and intensity. The potentiometer is programmed
to change the frequency or intensity by rotating it. The LM386 audio amplifier has
amplified your signal until it reaches the appropriate level to emit the sounds through
the headphones at the specified level. The microSD card reader module was used to
read the microSD card used as a flash memory, and the sounds were memorized.
Programming the microcontroller to perform automatic testing and wireless
module programming was the second major step in the source code because it gives
us the opportunity to escape the multitude of wires and cables and at the same time
gives us the opportunity to connect the audiometer to other devices or to connect
other peripheral components to the system. Thus, after the code was created in
the C++ program, it was stored on the Arduino MEGA 2560 development board.
An audiometer is capable of delivering tones between 125 and 16,000 Hz, the test
frequency being 125, 250, 500, 1000, 2000, 4000, 8000, 16,000 Hz, and the intensity
is amplified from 5 to 5 dB or 10 in 10 dB. In this sense, sounds were created using
the Fl Studio software (a virtual studio to create music), using a native instruments
massive synthesizer with three oscillators with over 40 wave forms, filters, stamp
modulator, frequency, etc (Fig. 6).
In this case, a single oscillator was used to generate the sinusoidal waveform,
since this is the basic form in acoustics, by the overlapping of the sinusoidal waves
the other signal forms are formed. During the tests, using a digital equalizer with a
visual panel, it has been found that the useful frequencies are somewhere between
Si (246.94 Hz B) and Do (261.63 Hz C), but closer to the Si basic frequency. In
this case, a single oscillator was used to generate the sinusoidal waveform, since this
is the basic form in acoustics, by the overlapping of the sinusoidal waves the other
signal forms are formed (Fig. 7).
The frequency was isolated using a more precise equalizer post using the “Peak
band” filter characteristic that is, leaving only the input frequency to pass. After the
desired frequency isolation, by removing the harmonics by leaving only the base
frequency to pass, pure tone was created, which was exported as a WAV audio file
at the 44.100 Hz sampling rate and 12-bit depth. To amplify the frequencies at the
required intensities (-10, 0, 10, 20 … 110 dB), Ozone 7 masked program from Izotop
was used. So, the audio files were loaded with the necessary frequencies, and the
equalizer was used to amplify or reduce the sound by 10 dB.
3 Results and Discussion
The audiometer features MP3 player-like features, where the sounds created in Fl
Studio are loaded onto a microSD card. With the card reader module, Arduino MEGA
2560 will play the sounds loaded on the card through the headphones each time we