>> I just realised something. If i use three op-amps in succession i 
>> will
>> get an inverted signal a the end. Same with only one op-amp.
RM> You need to do some basic study of amplifiers.
RM> A single stage amplifier CAN be designed to be inverting or 
RM> non-inverting. Those in your system are AFAIR all inverting, but it 
RM> doesn't have to be that way. The SIGNAL can be either polarity - the 
RM> feedback must be invertedto achieve negative feedback.

I read about the different ways an op-amp can be used and i know i
have my TL072 wired as inverting amplifiers. This is why i asked
because in the original schematic were three op-amps wired as
inverting amplifiers and this way (-) * (-) * (-) = (-) so the
original signal is amplified and inverted and this got me thinking
about why would it be this way unless the electret would output and
inverted signal itself.

>> On the other hand i saw on Jinx's schematic that he was using only 
>> one
>> transistor wired as common emitter which inverts a signal.
>> Am i going crazy here or the electret really spits out an inverted 
>> signal
>> of what it picks up ?
RM> The question does not make sense.
RM> What are you comparing the electret's output to?
RM> You can get the opposite polarity signal by just swapping the leads.
RM>         Russell

I was just talking about the normal way of wiring an electret, with
the pin connected to the case of the mic wired to GND. If I am doing
this then the audio signal will be inverted ?
If the mic outputs a voltage of +50mV this means that the correct
value to be interpreted is actually -50mV ?
I am asking this because if i have three op-amps wired in the inverting
mode then this is what actually results and what i get using a scope

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