Pre-amplifier for electret mic and Line-in audio sources

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You really need to read up on opamp theory and practice and then it will all start to make sense :)

If you have several different sources with each giving wildly different output voltages then the ideal solution is a separate input stage with the gain and response tailored to suit each one.
 
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Last answers for this... you need to do some research and read up on it all.

a/ Depends on what you want to drive with the preamp. Any opamp stage will easily drive any following preamp type input. A good audio opamp will drive 600 ohms to around -/+12 volts or higher given suitable supplies.

b/ For a line level stage the bandwidth a typical good design should cover at least 5Hz to 30Khz with no more than 1db loss at the high end.

Slew rate should be at least 2*pi*f*V where f and V are frequency and voltage. So 30kHz @ 12 volts peak require at least 2261946.7 volts per second, more commonly expressed as 2.26 volts/uS.

Now go and build your colour organ ;)
 
Sorry to bother you a lot. Just need a bit more clarification about a/ - Webench "Output Load" tab.
I didn't find description how to use it in TI docs. For this particular application, should be used Output Current or Resistive Load, and what values? Does the existing load can be considered as 'Current' load or Resistive Load?
 
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