Let's look at the datasheet of a typical electret condenser: https://www.mouser.com/datasheet/2/334/AOM-5024L-HD-R-1219369.pdf
What exactly do the resistor and capacitor do and how does one determine the capacitor value? Looking at the datasheet it looks like the max voltage of the capsule is 9V so adding a 2kOhm resistor limits the current to ~0.4 mA, which is the max current rating of the capsule. So, the resistor is limiting the current to the capsule. I don't understand why we have a capacitor and the physics of the capacitor in this design. Is my interpretation of the resistor correct?
Additionally, suppose we wire this for a 3.5mm TRS or TRRS jack. Presumably, the tip and ring on a TRS jack both provide a small positive voltage. How does the device separate out the voltage and the output signal from the mic and how is this wired? For a TRRS configuration assuming CTIA standard, I'm guessing the sleeve provides this voltage and also is the output?
+---------------------------- battery +ve (3 to 12 Volts) | 2k2 R1 | o---------- 10uF ------o----- output |+ | CAPSULE 10k R2 |- | +----------------------o----- GND, and battery -ve
This is the basic electret microphone powering circuit which you can use as generic reference when receivign circuits which use electret microphones. The putput impedance is determined by R1 and R2. If you leave out R2 the output impedance is roughly the resistance of R2.
Finally, this 10kOhm resistor connected between the output and the ground, is confusing me, as well as the statement in quotes. What does the 10k resistor do and how does not including this leave the output impedance roughly half the resistance of R2 (now left out of the circuit)?