I stumbled across this. I haven't read it yet, although I will, maybe it will give me a clue about transistor technology. Someone here might find it useful.

http://www.electro-tech-online.com/electronic-books/36605-guitar-amplifier-book-teemu-kytt-l.html

steven

Thanks a lot for sharing this.
Haven't read it yet neither but i learned something whilst glancing at it , so it must be full of information

Regards Mathias