Bandwidth

The bandwidth was measured using the HP3562A spectrum analyzer using the Sweep Sine analysis mode. The result is presented in the image below. Load is 4 ohm purely resistive

Please note the 0.25dB/div vertical scale. The low frequency overshoot is due to the input bootstrapping; if you don’t like this aspect it can be easily controlled by adjusting the value of the non-polarized electrolytic capacitor in the feedback loop.

The original bandwidth requirements are easily met. The amp gain is 28 or about 27.3dBv.