A microphone system comprising: a microphone array that has a plurality of microphones, each microphone configured to collect peripheral sound, convert the collected sound into input sound signals, and output the input sound signals; and a microphone sensitivity difference correction device comprising: a detection section (16, 216) configured to detect a frequency domain signal expressing a stationary noise, based on frequency domain signals of the input sound signals respectively input from each of the plurality of microphones that have been converted into signals in a frequency domain for each frame, the frame constituting a unit in a consecutive flow of the input sound signals; a first correction section (18, 218) configured to employ the frequency domain signal expressing the stationary noise to compute a first correction coefficient that expresses the sensitivity difference between the plurality of microphones for each of the frames, and configured to employ the first correction coefficient to correct the sensitivity difference between the frequency domain signals for each of the frames; and a second correction section configured to employ the sensitivity difference of the frequency domain signals that have been corrected by the first correction section to compute a second correction coefficient that expresses by frequency unit the sensitivity difference between the plurality of microphones for each of the frames, and configured to employ the second correction coefficient to correct for each of the frames by frequency unit the sensitivity difference between the frequency domain signals that have been corrected by the first correction section. a microphone array that has a plurality of microphones, each microphone configured to collect peripheral sound, convert the collected sound into input sound signals, and output the input sound signals; and a microphone sensitivity difference correction device comprising: a detection section (16, 216) configured to detect a frequency domain signal expressing a stationary noise, based on frequency domain signals of the input sound signals respectively input from each of the plurality of microphones that have been converted into signals in a frequency domain for each frame, the frame constituting a unit in a consecutive flow of the input sound signals; a first correction section (18, 218) configured to employ the frequency domain signal expressing the stationary noise to compute a first correction coefficient that expresses the sensitivity difference between the plurality of microphones for each of the frames, and configured to employ the first correction coefficient to correct the sensitivity difference between the frequency domain signals for each of the frames; and a second correction section configured to employ the sensitivity difference of the frequency domain signals that have been corrected by the first correction section to compute a second correction coefficient that expresses by frequency unit the sensitivity difference between the plurality of microphones for each of the frames, and configured to employ the second correction coefficient to correct for each of the frames by frequency unit the sensitivity difference between the frequency domain signals that have been corrected by the first correction section. a detection section (16, 216) configured to detect a frequency domain signal expressing a stationary noise, based on frequency domain signals of the input sound signals respectively input from each of the plurality of microphones that have been converted into signals in a frequency domain for each frame, the frame constituting a unit in a consecutive flow of the input sound signals; a first correction section (18, 218) configured to employ the frequency domain signal expressing the stationary noise to compute a first correction coefficient that expresses the sensitivity difference between the plurality of microphones for each of the frames, and configured to employ the first correction coefficient to correct the sensitivity difference between the frequency domain signals for each of the frames; and a second correction section configured to employ the sensitivity difference of the frequency domain signals that have been corrected by the first correction section to compute a second correction coefficient that expresses by frequency unit the sensitivity difference between the plurality of microphones for each of the frames, and configured to employ the second correction coefficient to correct for each of the frames by frequency unit the sensitivity difference between the frequency domain signals that have been corrected by the first correction section.