Help with a multistage NPN BJT audio amplifier
Your output stage has idle state Ic =0,8mA
The AC amplitude of the non-distorted output can be max. 0,8mA
AC current 0,8mA peak brings to 8 Ohm about 2,6 microwatts power. That's not especially loud although it can be audible in quiet environment with a sensitive speaker.
Calculations: P=0, 5 * R * Ipeak^2 = 0,5 * (8 Ohm) * (0.0008 amps)^2 = 2.56 millionth part of a watt = 2.56 microwatts = 0.00256 mW. That's about 56 dB below 1 watt. If you happen to have a decent sensitivity small speaker which makes noise level = 90 dB over the standard hearing treshold at 1 meter distance you'll get generous 34 dB audio noise level which is only 1 dB less than what's considered to be good enough silence in usual living rooms at daytime. In bedrooms in sleeping time it's 4 dB too loud as a silence.
The design should start from the wanted power and gain.