impedance matching

[w4bfs]

It comes up all of the time .... I have a low impedance microphone so I can't use a high impedance microphone input, right ?  What if I have the converse, that is a high impedance microphone: can I use the low impedance input ?

This is not so hard but requires a bit of understanding of what is going on in the circuit in your application

Generally (there are exceptions) impedance matching is most important when you are trying to transfer power from one stage to the next.  The best condition for this is a matched impedance.  This match can occur in several ways using multiple techniques.

If you are not transferring power but rather a voltage then impedance matching becomes less rigorous and more a case of following electronic rules to avoid improper operation.  so here goes ...

1.  You may follow a low impedance output with a high impedance input stage.  The low output impedance microphone output can usually drive the high impedance input without problems.  Other circuit considerations notwithstanding.

2.  You may not follow a high impedance output with a low impedance input .... This is just wrong and will excessively load the driving stage with attendant distortion and screwed up frequency response.

this is just the quick-and-dirty on this