Connect the output to a Digital Storage Oscilloscope to see the variations in output with the sound signals on electret MIC.
Low noise electret MIC pre-amplifier module can be used to sense sound signals and to amplify it to a high voltage. This module can be used with a power amplifier to make MIC and speaker circuit. This can also be used as sound sensor module.
Operating voltage – 9V
Working of low noise electret MIC pre-amplifier module : http://www.haberocean.com/2019/08/working-of-low-noise-electret-mic-pre-amplifier-module/