https://michaelkrzyzaniak.com/marshma...

In this video I record through a window using a Black, High Gain Metal Marshmallow contact mic. Each audio clip was independently normalized so you shouldn't necessarily be listening to the absolute loudness of my voice,, you should be listening to the sound of my voice relative to the background noise. To make a regular recording of voice in a quiet room you should definitely just use a normal microphone. If there are loud sounds on the opposite side of the glass from the sound source the contact mic is definitely way better, and even good if you lean in and speak loudly, but it is not perfect. If the noise is on the same side as the sound source, I think the contact mic is still better. However, distant sounds seem to attenuate more slowly in the contact mic than through the air, which could be good or bad, depending whether it is the sound source or background noise that is at a distance.