You need to pair this book with the internet. Use it for the circuit topologies, the PCB layout guidance, and the safety rules. Then, go to Mouser or DigiKey with your phone to find modern equivalents for the transistors.
Slone (a legend in the DIY audio community) assumes you know which end of a soldering iron is hot, but he doesn't leave you hanging if you're shaky on Ohm's Law. the audiophile's project sourcebook
You want to understand why your stereo sounds good. You like the smell of solder. You want a 400-watt amp for the price of a nice dinner out. You need to pair this book with the internet