OL> Dumitru Stama wrote:
>> http://electronica.asm.ro/electret/scope.html
>> After removing the 10nF compensating caps and putting 100pF ones
>> instead the circuit works very well and the gain can be seen. Now i
>> have that mic-noise problem :)

OL> Actually it looks like you have an excessive gain problem.  The shape of the
OL> waveforms on the last scope trace clearly shows clipping.  Now it's time to
OL> insert a volume control (really variable gain reducer).  I would put it
OL> right after the first stage.  Then you can crank down the gain to where the
OL> output voice sounds reasonable, and I think you'll find the noise will be
OL> mostly the normal ambient sounds the microphone is picking up.

I can do this, no problem. So this means replacing the feedback
resistor (R8) from the second stage with a 200K pot ? I think
this way i can control the gain from ~200 to ~4000

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