Recording conversations for later retrieval

So we have our audio gear all configured and ready to record—let's get sneaky with it!

Picture the following scenario: you know that something fishy is about to go down and you'd like to record whatever sound that fishy thing makes. Your first challenge will be to hide the Pi out of sight with as few cables running to it as possible. Unless you're working with a battery, the Pi will have to be hidden somewhere within a few meters of a power outlet.

Next, you'll want to connect your USB microphone and keep it hidden, yet uncovered if possible, to avoid a muffled recording. Unless you expect the action to take place right in front of the microphone, you should set the capture signal to the max with alsamixer for the microphone to be able to pick up as much of the room as possible.

Now, all we need to worry about is how to trigger the recording.

Writing to a WAV file

The Waveform Audio File (WAV) is the most common file format used for recording audio...