QRV-04 - The high performance SMD headphone amplifier with multiple feedback

Click on the picture to see a preview of the pcb.

Interesting features:

1. The pcb fits virtually any single opamp with or without offset trim.
2. Room for good coupling caps (if you must or like), both SMD and regular hole mounted, if you are having trouble in finding big SMD caps.
3. Input LP-filter if you have problems with RF interference (you should have a filter though).
4. Room for DC removal cap (if you need this).
5. Crossover distortion reducer for the opamp. This is a popular circuit in the DIY community.
6. Current limitation inside the feedback loop (choose the value you like)
7. High speed and high performance SMD buffer as output stage.
8. Local feedback for stable performance (only if necessary).
9. Multiple feedback as an option.
10. High quality power supply with large smoothing caps and transformers on the pcb.
11. Fits any headphone (except for electrostatic of course).