The attached Circuit is supposed to give an amplified signal to a speaker of 50 Ohms, the common emitter gain AV is about 95, Rout is around 1.7K and the input impedance of the Follower is about 5K and its output is 50 Ohms, the issue is mis-match impedance I am having between the 1.7K CE output impedance and 5K input impedance of the buffer. It’s like a puzzle I could not make my buffer input resistance at least 10 times higher than my CE output impedance without affecting the output impedance of the follower which is supposed to be around 50 ohms to drive the speaker. I also tried using a voltage divider technique instead of self-biasing to overcome this mismatch impedance issue but I could not get it to work. I used R1=60K and R2= 47K, and RE=300 ohms for the buffer, instead of R(B)=215K. I basically get nothing out to the speaker. Any body can think of how this can be resolved. I know there are other ways of designing an amplifier among which is the use of MOSFETS or Darlington configuration.
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