Sound acquisition device

A sound acquisition device for use with an object having a first member defining a first space and a second member defining a second space together with the first member, the sound acquisition device comprising:

• a substrate having a substrate sound hole communicating with the first space;
• a first microphone disposed on the substrate and configured to acquire sound generated in the first space via the substrate sound hole;
• and
• a second microphone disposed in the second space and configured to acquire vibration sound generated by the second member, wherein
• a coherence of the vibration sound acquired by the second microphone with respect to the sound acquired by the first microphone is 0.4 or greater.