I simulated your amplifier circuit. The input has a transistor that pulls up the voltage very well. But it has only a resistor to pull the voltage down. As the voltage gets lower then the current in the resistor becomes too low to work properly. Then the bottom of the output waveform clips.
You need to replace the pull-down resistor with a constant current sink or "a boostrapped" pair of resistors.
Your amplifier doesn't have a voltage gain, it has a small loss.
You need to replace the pull-down resistor with a constant current sink or "a boostrapped" pair of resistors.
Your amplifier doesn't have a voltage gain, it has a small loss.