Here are some of the PCB design examples
Headphone Amplifier/Pre-amplifier by Juma (diyaudio)
APEX AX-14 Ultimate fidelity Power Amplifier. (Mr. Mile Slavkovic- diyaudio)
Juma Buzquito Amplifier (diyaudio)
Hi-Fi Headphone amplifier by Fab (diyaudio) (customer sponsored-posted here as per customer wish)
AKSA RANCHU32 Very Simple Quasi Complementary Amplifier (diyaudio)
Mosfet Amplifier Designed for Music- By Mooly ( https://www.diyaudio.com/forums/solid-state/119151-mosfet-amplifier-designed-music-post5544701.html )