Firstly, any book on vacuum tube audio is or should be welcome, there aren't enough of them. It takes lots of effort to write and produce such a book, so that is the first star from me. Unfortunately, this is where the problems start (from the very start).
1. The first two chapters (almost 50 pages) are not necessary.
2. The title of the 1st chapter is totally wrong, it is NOT an overview of Vacuum Tube Audio Applications at all, but a weak overview of AC and DC principles, you will not learn much from such a superficial scan of hodge-podge topics such as "Dimensions of Hearing" and "the Atom" A drawing of an iron (FE) atom in a book on building tube amps???
3. The 2nd chapter is better, but again, not deep or practical enough, and as such, not necessary.
4. Some sections of Chapter 3, such as "Electron Optics" again have no place in a book of this kind. The computer "drawing" of a triode's construction on page 60 is weird, totally wrong or impossible to understand! The family of plate curves and transfer curves on page 78 show only the linear parts of the curves, this is NOT what real curves look like, misleading!
5. The choice of circuits used as examples in Chapter 4 is strange, only one type of phase inverters is shown, and the section on "protection measures" does not mention any such measures, simply talks in general terms about maximum grid dissipation.
6. Chapter 5, Interconnection, Layout and Operating Environment" is a total miss, a very shallow overview of an otherwise important topic.
7. The language used throughout the book is very strange, very bureaucratic, such as: "A vacuum tube suffers wear-out because of a predictable chemical reaction" and then it continues "The cathode is the heart of any tube" without saying what that chemical reaction is and why is it important and why is the cathode the heart of any tube. Again, so is the heater, and the anode, and the grid ...
8. Chapter 6 is so-so, but the photograph on page 148, showing 25 or so Heathkit instruments is weird. The caption says "Test equipment for audio project construction". You don't need most of these to build an amp, you may need a few basic ones to test it (such as a dummy load, a function generator, a multimeter and perhaps a scope).
9.The choice of tubes in Chapter 7 again is strange. No 6L6, no EL34, no 6BQ5, no 6SN7 or any other commonly used tubes.
10. Page 189 is the REAL start of the book and this is where in my view the biggest problem with the book becomes obvious, and that is its unsound methodological approach. For instance, the first power supply project is a regulated power supply. Why not start with an unregulated supply (90% of commercial amps do not use regulated power supplies), measure its performance, listen to both amps, then compare it with the regulated power supply IN THE SAME AMP? That would show the readers the benefits gained so they can decide if the prize is worth the price (complexity, cost, etc)
11. The first of many PCB (or what the author calls PWB) designs is given here. Using PCBs in hi-end audio in my view is wrong, it over-complicates things, point-to-point wiring is much easier for constructors. PCB have only one advantage, and that is faster mass production. They have no place in making a one-off amp!
12.There are quite a few errors and omissions in the book, to many to list here, one is on page 214, where a simple phono preamp diagram shows the use of a guitar jack at the input!?
13. On page 254 the author says "Hammond (and perhaps other manufacturers) describes this as "ultra-linear operation." With billing like that, the author had to try it out." It seems the author had never heard about UL circuit or theory of operation before, patented by David Hafler (of Dynaco fame)and Herbert Keroes in 1951.
14. The literature suggested again is very weird, you will not find books by Morgan Jones or the "Radiotron designer's handbook", but you will find books such as "Maintaining Electronic Systems" What the &%$@?
In conclusion, I cannot recommend this book to anyone, despite my best intentions. It does not contribute anything new to the field, and should be read (but only the second half, after page 189) as one person's experience in building two of the designs from the RCA tube manual, nothing more and nothing less.
