Hi
when i want to design a preamplifier using BJT and need to have a maximum symetrical voltage swing at the output, then two conditions must be satisfied:
1- VCE = 0.5 VCC
2- I (saturation) = 2 IC
Is there other conditions must be taken into acount?

 

You could get an audio grade op amp, like an OPA1641. With symmetrical supply rails, the signal output symmetry is pretty much guaranteed. You get better input impedance and flatter response, as well.