I purchased the first edition of Robert Harley's book about Hi-Fi. I was hoping to find the kind of info you want (how amps work, crossovers, etc.). His presentation was at a very high level, however. It would be nice to know how capacitors, resistors, global feedback, etc. fit into the picture. Try to find a book about building a simple radio receiver. This will give you some education.
Jimmy, I think what you are looking for is one of the books written back in the 1950’s, by guys like Harry F. Olsen. A technical book, with electronic theory and principles for aspiring audio engineers. Don’t bother with an "audiophile" book---writers of them speak in subjective language, not technical.
By the way, if you’re in the San Francisco Bay area, Roger Modjeski of Music Reference is teaching a class in amplifier design. Taking that class would be a great way to both learn audio engineering and build your own tube power amp. If I still lived in my hometown of San Jose, I’d do it myself.
Douglas Self on amplifier design: http://www.douglas-self.com/ampins/ampins.htm
Floyd Toole on speakers and room acoustics: https://www.amazon.com/Sound-Reproduction-Psychoacoustics-Loudspeakers-Engineering/dp/0240520092
The bible is here and has never been equaled IMHO: Audio Cyclopedia by Howard M. Tremaine, 1969. A little expensive (~$120) and huge at 1,700 pages, but it has EVERYTHING including audio designs and history. Also found on eBay.
For some pointers on cables and various cable geometries (i.e. how they are constructed, take a look at this link...
It mainly deals with DIY cables but it also explains the benefits of different cable materials, geometries/, connectors
If DIY is not your thing then I would take a look at Anticables products - they are very good and reasonably priced.
If you want excellent performers then take a look at KLE Innovations products - they really outdo most other cables - even their entry level cables outperform most others
The link is my site, so if you have any questions ask away.
The definitive book on loudspeaker and room interaction is this one by Floyd Toole, recently updated to a third edition.
My suggestion, and what's worked well for me, dig into DIY. I suggest starting with Nelson Pass. He makes things very understandable and his designs are easy to build. Mr. Carlson's Lab on YouTube is excellent material too. The scope of his channel goes way beyond audio, but he's very good at explaining things and he's started a Patreon where he's teaching electronics starting with the bareknuckle basics. Burning Amp lectures are good stuff too.
I kinda think you're right. It seems to me that when somebody starts getting a grip on electronics they stop believing in the snake oil and myths which seem to be the litmus test for being a "real" audiophile. The more I learn, the more I go by the numbers, the better my stereo sounds, and the less I'm a legit audiophile I am because I don't just listen to anything cluelessly.