Questions:
1) How would you rate this drawing? It could be the best in the world, I just have no idea myself.
2) How does the 2550 compare to the 2204? I've never played a 2550.
3) There is a "black box"-looking device just next to the bias supply on the board. Vas ist das?
4) Is there a schematic for this amp?
![Image](https://www1.picturepush.com/photo/a/12508562/img/Anonymous/TL-2555layoutR10.jpg)
Thank you!