Rod's book is excellent and highly recommended for home studio applications. The other one I like a lot is Recording Studio Design by Philip Newell -- although it leans more in the direction of big-budget pro studios there are still plenty of good ideas and advice. If you want more of the acoustics theory, terminology and number-crunching, then the Master Handbook of Acoustics by F Alton Everest is the way to go!
I don't think Ethan's book is ideal for your purposes, but I reviewed it for SOS here:
Technical Editor, Sound On Sound...
(But generally posting my own personal views and not necessarily those of SOS, the company or the magazine!)
In my world, things get less strange when I read the manual...
There is also: Acoustics and the Performance of Music by Jürgen Mayer, which is excellent and shows the radiation patterns of musical instruments. I have a 1st edition and the new 5th edition.
It's an excellent and fascinating book, John, but not of much help in understanding the theory and practice of room acoustic treatment which is what the OP was after.
Technical Editor, Sound On Sound...
(But generally posting my own personal views and not necessarily those of SOS, the company or the magazine!)
In my world, things get less strange when I read the manual...