On the left is a swatch of code that I wrote to read the analog input from the microphone circuit and print it to the serial monitor. On the right is the serial monitor.

Under normal circumstances, the value read at analog pin 1 hovers close to a value of 536. This constitutes ‘quietness,’ and no value is sent to the serial monitor.

Then I took a pair of wooden blocks and clacked them together a couple times over the microphone. That’s when the readings appeared on the serial monitor.

So the circuit works, though I’m not sure it works well enough to work as a room noise monitor. I hope it’s just a matter of tweaking resistor and capacitor values. Another thing, I’m testing this late at night in my apartment, so I can’t very well test it with some really loud, continuous noise lest the neighbors complain.

At any rate, I have other things to do at the moment and will have to put aside this project until next week, when I hope to test and tweak the system under ‘field’ conditions.