So I have a project on which I need to receive audio input (musical notes with distinct frequencies say from a piezoelectric buzzer for example) through a microphone and identify what notes were played. Later on, displaying my results through a led matrix (note played and duration).
So, I started looking for a microphone I could use with the arduino and found the ky-038...... So I tried using it.... I was checking the analog voltage and it constantly outputs a voltage whether there is sound or not...... why is that? is it because of the noise of the environment???
Furthermore, what does adjusting the potentiometer on the circuit do??? I noticed that as I turned the potentiometer the output analog voltage changed reaching two a maximum and minimum namely 5V and 0v
will such a microphone be sufficient to get a clear input in terms of signal strength (quality) ??.... the output from the microphone will then be going to a group of filters in parallel..... according to which filter the high signal is received from the note will be identified...
Thank you all
Give us a clue please.
Link to WTF you are talking about. Until then we can only guess.
A proper audio input should read about 512 with no sound due to the biasing of the signal. The with sound you get readings above and below that value. The louder the sound the further the readings are away from this no sound reading.
Thanks.
That board has two outputs an amplified analogue output for connecting to the analogue input. This is marked A0.
The other is a digital output marked D0 and is for connecting to a digital input. The other pins should be connected to +5V and ground.
Furthermore, what does adjusting the potentiometer on the circuit do?
It determines the amount of sound you must have before the digital output changes. In other words a digital threshold.
will such a microphone be sufficient to get a clear input in terms of signal strength
Probably but you will need to experiment.
the output from the microphone will then be going to a group of filters in parallel..... according to which filter the high signal is received from the note will be identified...
OK but what sort of filter, a second order RC is not going to cut it, you need a higher order. Even so your chances of being able to determine the frequency and hence the note is low. You stand a better chance doing an FFT on the input waveform. Even so determining the note is not guaranteed.
Thank you sir, it's much appreciated...... 
What is FFT btw so I can start doing my research on it...
any nice links would be great!!