A simple topic for people who change the Pi Zero to a Pi 3,
For activate the audio output :
sudo /boot/config.txt
Uncomment the ligne : dtparam=audio=on
If you install a GUI I recommande you to change the GPU memory
gpu_mem=16 to 320
For use the rpi at normal puissance change the following value
arm_freq=400 to 1400
core_freq=250 to 400
It’s the Default value