The audio amplifier boosts the analog audio signal to drive a speaker. You can use a dedicated amplifier IC or a simple transistor-based amplifier.
If you want to create a more traditional CD player experience, you can add a front panel and buttons to control playback, pause, and track selection. cd player diy
The DAC converts digital audio signals from the microcontroller to analog signals that can be amplified and played through a speaker. You can use a dedicated DAC IC or a microcontroller with a built-in DAC. The audio amplifier boosts the analog audio signal