That's pretty decent 20 euros .   I'm a total novice so forgive me if i say something stupid which is likely if we were to talk about electronics for any length of time.   Any way looking  at the schematic i worked out that the bottom bit is the charger . ( not the voltage splitter)  ...

This looks really awesome , i would  like to know how its performing .   Whats the battery life ?   DC offset ?   Output current ?   Is it able to power those really demanding headphones like 68ohm ?   I had a look at the prototype schematic , have a few questions about it if...