So during my construction of the Alice Microphone, I put together the circuit and was able to pass signal (noise) but couldn't capture audible noise such as speech or intelligible audio. I figured doing a little research on the parts would help. I've started with the main part of the circuit, the JFET (Junction Field Effect Transistor).
After doing some reading, the JFET is the most commonly used transistor in Electret Condenser Microphones (ECM's) being that it serves as a high impedance buffer/amplifier for Analog to Digital Conversion at the input stage. As most of us know, an ECM holds a pre-charged voltage in its capsule. When the sound pressure enters the capsule, the moving plate will adjust accordingly, thus changing the capacitance and output voltage.
Below you will find some of the benefits of a JFET when it comes to ADC.
Here is the link to the site http://www.ti.com/lit/wp/snaa114/snaa114.pdf
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