I designed a multistage amplifier circuit to meet my needs of have a load of 20 ohms, a gain of 200 and a input resistance of 150k. I used a CC-Common Emitter with partial bypass (gain of 10), another CE w/partial bypass (gain of 20), and a CC at the end. I did all my calculations and I got my circuit doing everything I wanted on multisim. My questions is how could I downsize this circuit with using an op-amp(741), I built another circuit on multisim that gets me my gain of 200 with using an non-inverting design, my key issue is since i need a input resistance of 150k, I know that op-amps have very high input resistance, I just don't understand if the second circuit is good enough since its input resistance is much much higher then the 150k.