Test the Acoustic Microphone

About this task

The sensitivity of the acoustic microphone can be measured to test its functionality. The Test microphone readout measures the volume of the incoming signal from the acoustic microphone with a bandpass filter applied at 1 kHz. This readout is designed for use with a standard microphone calibrator.

A standard microphone calibrator will produce a 1 Pa / 94dB SPL, 1 kHz tone at a fixed distance from the microphone. The calibrator must be compatible with 0.5′′ diameter microphones.

Important:

This procedure is only valid for third-party microphone calibrators that emit a calibrated, 1.0 kHz sine wave at a volume of 94 dB SPL.

Procedure

  1. In the Song Meter Configurator app, open the Utilities menu:
    1. Pair the Recorder with the Song Meter Configurator App.

      Configure and Unpair icons will appear next to the recorder's name.

    2. Tap the Configure icon for the paired Song Meter Mini 2 in the Recorders screen.
    3. Tap the Utilities icon in the upper-right corner of the Configuration Editor.
  2. In the Utilities menu, tap Test microphone.
  3. Close the lid of the Song Meter Mini 2.
  4. Remove the foam windscreen from the acoustic microphone.
    A Song Meter Mini 2 with only a left microphone. The foam windscreen has been removed, exposing a plastic cylinder that houses the microphone.
  5. Connect the calibrator to the acoustic microphone according to the calibrator's instructions.
    Many calibrators require the microphone to be inserted into the calibrator.
  6. Turn the calibrator on.
  7. If the calibrator has the option of multiple test frequencies and amplitudes, select 1 kHz and 94 dB SPL.
  8. Observe the amplitude reading in the Test microphone window. If the value is higher than -16 dB, the microphone has passed and is ready to use. If the value is lower, the microphone has lost some or all of its sensitivity and should be replaced.

    dBFS readings in the Test microphone window are negative numbers, so a "higher" value than -16 dB is one that is closer to 0 dB. For example, a reading of -10 dB would pass, while a reading of -20 dB would fail.

    The Test Microphone window displays a level reading for each attached microphone in decibels (dB).