Hello guys. I'm trying to make an arduino guitar tuner. I'm using MAX9814 microphone. Do you know any library to get frequency from microphone? I need of 1 Hz resolution.
I'm still learning the arduino libraries but I can help with some general information.
First you will have to convert the microphone output from an analog signal to a digital pulses.
Assuming the analog signal is reasonably close to a sine wave, a simple circuit that senses whenever the signal goes from minus to plus and plus to minus. If your arduino has a comparator that would work fine (be careful to use a series resistor to limit the current when the signal goes negative as the arduino will not accept negative voltages).
Next I would look for the arduino counter function that can count the input pulses. A guitar ranges about 80 to 1000 Hz so the pulse rate is 12.5 ms to 1 ms. You would need to resolve 1 µsecond (or 0.001 milliseconds) to be within 1 Hz at 1000 Hz. You would then count the number of pulses for 1 second, calculate the frequency and display.
You should be able to find counter functions to build the functions you need.
Did you already search the forum.
This must have been done before.
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