Customer Reviews

Valve Amplifiers (2nd Ed.)

5 star:		(15)
4 star:		(8)
3 star:		(2)
2 star:		(1)
1 star:		(0)

 

 

Fifteen years ago, tubes (valves to the rest of the world) were not only out of style, they were almost extinct. The same went for vinyl records. But there were always a few people that didn't buy into the new technology, insisting that tube electronics sounded more in step with the music. I heard my first high end tube amp (a Conrad Johnson MV-45) in 1987 and I've been hooked on the sound ever since. Thanks to a series of events that few could have forseen, the DIY tube revolution is in full swing. The fall of Communism and China embracing capitalism opened the flood gates, making more tube types cheaply available than since the mid-sixties. Add the internet with it's flow of information, and the underground DIY audio scene was born. There's an embarassment of riches now available to the amateur Hi-Fi enthusiast, and this volume is one of the best.

I've owned the first edition of this book for several years and it's absolutely great. It was a logical step up from my first DIY tube amp book, Bruce Rosenblitt's Beginners Guide to Tube Audio Design (now out of print). The first edition clocked in at 300+ information packed pages, covering everything from the performance of different electronic components used in tube amps, amp and preamp projects to chassis construction and design. When the second edition came out, I decided not to buy it thinking it maybe corrected some errors and had some new projects. Now that I've read the third edition, I have a funny feeling that I've missed out. See, the new edition is over SIX HUNDRED pages long, and that's without the amplifier construction section! The amplifier construction techniques are now covered in Mr. Jones' companion volume, Building Valve Amplifiers, in itself a 300+ page book. What this means is if you include the companion volume, there's THREE TIMES the information than in the first edition, over a thousand pages! Not only is there more, but it's better organized and edited than the first edition.

Morgan Jones covers just about every tube related subject, not hesitating to offer his opinions along the way. He doesn't hide his dislike for some current tube audio trends, such as tube power supply regulators and single ended amplifiers. There's a single ended amplifier project in the book, and while it's not a 300B amp project (he rightly says there are enough of those around), he goes through the project with all the thoroughness and care we've come to expect. There are several other projects, including a tube headphone amp, the author's original EL84 amp, a more powerful push-pull amp using 13E1 output tubes, his original "practical pre amplifier" from his first edition, plus a balanced preamp and a new line preamp and phono stage.

The wonderful thing about the projects in this book is that the author doesn't just present the schematic and say "build this", he goes through every step from tube and component selection to each design choice along the way. This isn't just a project book, this is a book that teaches you how to actually design an amp. I haven't built any of the designs in the book (yet), but I have no doubt that they sound very, very good indeed. And for vinyl enthusiasts, the amount of time spent explaining phono preamps is an absolute treasure. You won't find this information anywhere else!

Yeah, it's an expensive book, but worth every penny. The bottom line is this - if you're interested in DIY vacuum tube electronics and don't have this book and it's companion volume, you're limiting yourself. I think even crusty old timers that have been working with tubes for years could learn something from this book. If you've learned everything this book and it's companion volume have to offer, I believe that you could build tube audio electronics that compare to the best that are available, regardless of price.

If you don't know much about valve amplifiers ['valve' = `tube' in USA], you will learn a lot by reading this book, which starts from the basics. It is generally readable and easy to understand. In addition to theory, it also covers some very practical aspects [how to cut metal, how to solder, and so on]. The author's style is highly enthusiatic but came across to me as being slightly amateurish.

Its focus is on hi-fi audio amplifiers - it does not touch on valve guitar amplifiers.

What I liked most was the author's down-to earth common sense approach, which he evidently acquired through his training at the BBC. [no nonsense about gold plating your mains fuses here]

What I liked *least* were minor misconceptions and the details he gets wrong here and there. As a few examples, if you took him at his word, you would believe:

- Fitting metal screening to an input valve will shorten its life.

- The B-H curve of a transformer's iron can be treated as the Vin - Vout characteristic.

- The getter in a valve is only effective if the heater is hot before the anode voltage is applied.

Two topics I thought were significant omissions:

- How to measure amplifier characteristics [eg frequency response, power output, distortion].

- How to design feedback amplifiers to get the best performance for a given output transformer.

Troubleshooting [a pretty important topic] is only touched on.

As I said, if you don't know much about valve amplifiers, you can learn a lot from this book and will find it easy to read with lots of useful information. But if [like me] you are put off by incorrect details and a slightly amateurish air, leave it on the bookshelf.

I give Jones high marks for several reasons:

1) Comprehensive coverage of vacuum tube phono (RIAA) preamp design and optimization, the best in or out of print as far as I know;

2) Overall organization and breadth;

3) Technical explanation at a useful (not excruciatingly hard but not oversimplified) level;

4) Readable style.

While I am not as committed a believer as Jones is to the supremacy of push-pull amplification, I recommend this book frequently and with enthusiasm.

Is it perfect, the best possible book for the tube audio enthusiast ever to be written? No.

Is it the best book available? A resounding yes.

-j

There are very few young people today that know what a valve amplifier is, let alone having heard one. Most probably think of those humming old radiograms (seen in the movies) in the early days of radio when the valve itself was still undergoing refinement. The modern valve amplifiers give by far the warmest richest sound that can be wished for in an amplifier - and they DO NOT HUM. I am an avid suporter of valve amplifiers. I firmly believe that the transitor to take a valve's place in audio amplifiers has still to be manufactured. This book takes the novice through a wonderful discovery of the valve.

This book is notable since it is one of very few current textbooks that goes to the trouble of explaining in relative detail (a full treatment would require several volumes) on how amplifiers work. I am a teacher at a technical college and have found great use for this book in my lectures. In my experience students have a greater understanding of the complexity of the transistor once they fully understand the valve.

Enough said on education. What grabbed me is how this book guides one to the actual building of an amplifier - this being my hobby. I think that anyone that has heard a well designed valve amplifier in action and has a little electronic background ought to buy this book and work through it. It is immensly gratifying to design and build one's own valve amplifier. Especially because a valve is far more tolerant to the misuse of a novice designer than any transistor.

I wanted a book that would help someone build a vacuum tube amplifier who understood basic electronics but who had no prior experience with vacuum tubes (or valves as the British call them). This book was the answer to my search. Morgan Jones does a great job with the book. There were some minor (editing?) errors but these were of no great consequence. From the education in the book, I was able to build a single ended monobloc amp for about $500 which sounds a good as some commercial tube amps costing $5000 (my unbiased opinion)

Morgan Jones is an ex-BBC engineer - it shows! His techincal knowledge is excellent, his presentation is clear and easy to follow. Here's the big BUT - like the BBC - there is little creativity or 'daring' in his designs. His project is based on something he did 20-odd years ago and did not excite my imagination. A very good introduction (I enjoyed it immensely) but I think that Rainer zur Linde and Menno van der Veen have more to offer in extending thermionic technology.

Jones takes a very practical yet comprehensive approach to the design of valve amps and preamps. I've built quite a few over the years and was skeptical that I would get much out of this book, yet every chapter had some nuggets in it that either I didn't know or systematized previously unconnected things I did know. Hours and hours of fun. And really well-written. Excellent work, and I've recommended it to everyone I know with an interest in the subject.

This book gives a good overall review of tube amplifier design, and has descriptions of the major amplifier topologies such as push-pull, single ended, and output tranformerless. He also covers pre-amp design, and components. The author does tend to dismiss all types other than push-pull pentode as being frivolous. Consequently, most of the output amplifier circuit designs where he goes into detail, are P-P pentode. Nevertheless, no matter what kind of tube amplifier you are designing or modifying, you will find some useful information in this book.

I have poor understanding of electronics, but this book explains well all concepts, and is enough easy to follow.
To me is a book to read again and again to absorb new concepts, explained in a plain and easy form.
Very practical, lot of examples, not too much teory.

the book is the best of two worlds
It's well written and gives the bare minimum of theory you have to know to jump on the soldering iron without too much fuss about maths
Numerous ,practical exemples are given with clear schematics
In my opinion this is the very best book you can begin with when dealing with audio tubes amplifiers