Linear electret microphone amplifier for measurement purposes

Together with an electret microphone cartridge like Panasonic WM-60A, WM-61A or Monacor MCE-2000, MCE-2500 you get a very linear measurement microphone that can be directly connected to line in of your sound card. It is suitable for measuring speaker response or room response. The gain is +20 dB or +30 dB, depending on the setting of J1.

The amplifier will not work with the modifications to the microphone as suggested by Siegfreid Linkwitz to improve the high level linearity.


circuit diagram


Photo of electret amplifier module