Try doing it like this:

 

Try doing it like this:

This works very well! One question: Is the value of R5 (470k ohms) arbitrarily high, or is it a very specific value?

Thanks for the help!!

 

This works very well! One question: Is the value of R5 (470k ohms) arbitrarily high, or is it a very specific value?

Thanks for the help!!

It's fairly arbitrary (i pulled it out of my hat), but make it smaller and two things happen:
1. Your low frequency corner goes up unless you change C1.
2. Your power supply rejection will get worse unless your mic output resistance (Rmic) is very low (I assumed 1k in the simulation). This is because a small amount of supply noise will show up on C3, especially at low frequencies, and Rmic/(R5+Rmic) is a voltage divider. It really isn't an issue unless your supply has noise or ripple on it.

 

It's fairly arbitrary (i pulled it out of my hat), but make it smaller and two things happen:
1. Your low frequency corner goes up unless you change C1.
2. Your power supply rejection will get worse unless your mic output resistance (Rmic) is very low (I assumed 1k in the simulation). This is because a small amount of supply noise will show up on C3, especially at low frequencies, and Rmic/(R5+Rmic) is a voltage divider. It really isn't an issue unless your supply has noise or ripple on it.

ohh, ok.

It seems to work very well now with the modifications you provided. I added a potentiometer to the feedback loop to give a little more flexibility.

The output impedance of the mic is rated at 680 ohms. I assume increasing the impedance (to 1k ohms) of the signal will have no negative effect?

 

ohh, ok.

It seems to work very well now with the modifications you provided. I added a potentiometer to the feedback loop to give a little more flexibility.

The output impedance of the mic is rated at 680 ohms. I assume increasing the impedance (to 1k ohms) of the signal will have no negative effect?

Do you mean will it still work with 680 ohms? It will.
If that's not what you mean, clarify your question.

 

If your power supply is clean, you could get by with the simplification below.
If you hear hum, use the first circuit.

Don't forget power supply decoupling caps (100nF and 10uF) from +V to GND on the op amp.

 

ok, here is my updated schematic with a 10uF cap applied to V+. I decided to keep all of the precautionary capacitors elsewhere in the circuit and changed the 100nF capacitor to 10uF as specified in the example mic circuit in my microphone's data sheet.

 

Do you mean will it still work with 680 ohms? It will.
If that's not what you mean, clarify your question.

Yeah, that's what i meant. Sorry for the confusion.

 

ok, here is my updated schematic with a 10uF cap applied to V+. I decided to keep all of the precautionary capacitors elsewhere in the circuit and changed the 100nF capacitor to 10uF as specified in the example mic circuit in my microphone's data sheet.

You don't need more than 100nF for the input cap, because the input resistance is 470k. With 10uF, about 30 seconds will be required from the time you turn on power until the output DC level is steady. With 100nF, it will take about four seconds.
Are you digitizing audio?

 

You don't need more than 100nF for the input cap, because the input resistance is 470k. With 10uF, about 30 seconds will be required from the time you turn on power until the output DC level is steady. With 100nF, it will take about four seconds.
Are you digitizing audio?

Attempting to, yes.