Common emitter amplifier gives an amplified inverted output. So if I fed the inverted output to a speaker, would it sound fine ? If not, how do I get an amplified but non inverted output from a common emitter biased transistor ?
In general, the absolute phase of audio signals doesn't matter.
But if it's a problem, just reverse the leads to the speaker!
You could get an inverted vocal signal by rotating a microphone 180 degrees - does this sound bad? Given all the reflections going on when you record live music AND all the reflections and acoustic reverb you get when you listen to music, it should be no surprise that doing a single electrical inversion has no audible effect whatsoever.
No, it would NOT sound fine. A single BJT common-emitter amplifier only provides an active sink or source for one quadrant. You need a two-quadrant driver for a speaker; one that can sink and source current to the speaker. And inverting the signal isn't important if all you are doing is driving a speaker.