I have a 3 transistor Class AB power amplifier that I referenced from a working design which has different design parameters and biasing than what I need.
How I intend on using it, it will be used to drive a 16 ohm 2W speaker and the input is an AC signal with maximum 6V peak. Vcc needs to be 10V. I want 2W max output which requires 5.65V on the output, therefore I mainly want unity voltage gain and only current gain.
The issue is that I did some calculations and changed the voltage gain to 1 by adjusting R4/R1, and lowered the Q-point by adjusting R3 & R4 to allow for larger headroom to prevent output clipping when the input increases, but using calculations for finding Class A amp biasing values don't work because of the biasing diodes used for the push-pull output pair. And even by playing with the Q-point I still get clipping above 1.7V, and lowering the Q-point further starts to clip the bottom peak of the output.
In the simulation attached the green waveform is the input, blue is output of driver transistor's collector, red is the output for a 2V input sine wave.
What can I change to allow for the full input voltage to be seen unclipped at the output? Is it possible to set a Q-point that allows for full voltage swing that I need (11.3Vpp)? What calculations do I need or does this circuit only work with small amplitude input signals? Do I need a different circuit entirely?
For context this will be used as the final stage in a guitar amp project. Thanks in advance.