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Okay here is my version of a preamp. The voltage gain is 1010. So let's go through the differences between this circuit and yours. First notice the way the bias chains are connected. Instead of connecting the 22kOhm and 41kOhm resistors to the + of the power supply, you connect them to to the collector of the transistors. This provides negative feedback by voltage and stabilises the output thermally. (you may refer to Thermal Drift in Semiconductors). See whenever the thermal drift pulls the collector voltage down, the base voltage also goes down struggling to rise the collector voltage again, thus stabilising the output. The 330ohm resistor provides negative feedback by current. It limits the current through the transistor. By adding an emitter resistor, you decrease the gain. The formula is the collector resistor divided by the emitter resistor. So ideally the first stage should provide 5600/330=17 times gain. By adding an emitter capacitor too, you decrease the negative feedback and ideally you may completely supress. I chose not to completely supress it by adding a 10ohm resistor to dampen the capacitor effect. On the second stage i added a similar emitter negative feedback you may see in some circuits with an LED. I won't go into detail here, you should only know that it also supresses the negative feedback and provides full gain, much like an emitter parallel RC circuit does. Now for the last negative feedback. So far we have a current and voltage negative feedbacks scattered around, now the last feedback is only by AC and provides a complete feedback (from output to input), whereas all other feedbacks are local. That's the 10uF/100k RC circuit. When you take a feedback from the second collector to the first emitter it increases the negative feedback and decreases the gain, but increases the linearity.
If you have any specific troubles following up, just tell me what can i try to clear up. Always a joy to help others dabble in the world of electronics.
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