would like to record specific audio for the following scenario. I have a piece of equipment that rotates a drum via an electric motor. The drum contains food product that is heated by air entering the drum. The food inside the drum cracks very lightly when it is fully cooked. The problem is that the cracks are audible, but barely. The whine of the motor and inflow and outflow of air is drowning out the audible cracks.I figured a solution would be a certain microphone that would concentrate it's sensitivity close to the drum, therefore avoiding all the background noise. Unfortunately I am NOT an audio expert in the least. What microphone would work for this setup? Any other tips with how to filter the microphone and process the audio in real time.I am a computer programmer so designing software would not be an issue for this. I mainly need help picking out hardware and fully understanding the problem domain so I can design a solution.