Actually, this is just some basic technical stuff that every hobbyist should already know. These are my, and any contributers', versions. There are explanations of the components and basic applications and opinions of the purpose and merit in audio.
WIRE
RESISTORS
CAPACITORS
TRANSFORMERS
POWER SUPPLIES
SOLDERING TECHNIQUES
PHYSICS
THE PSYCHOACOUSTICS OF TUBES
GEOPHYSICS and SOUND PERCEPTION
MUSIC
NEGATIVE FEEDBACK
THE SOLID STATE TUBE
FFT VS the OSCILLOSCOPE
VISITATION RIGHTS