Customer Reviews

High-Power Audio Amplifier Construction Manual

5 star:		(45)
4 star:		(6)
3 star:		(4)
2 star:		(7)
1 star:		(5)

 

 

... Randy Slone regurgitates no one; he states in his own words, clearly and in accessible language for the non-specialist, established principles of solid state amplifier design, and places these in the context of his suggested projects. One chapter is devoted to twelve "ready-to-construct" cookbook designs, and full-size PC board artwork for several of these are provided in an appendix. In short, if you want to build and/or design your own audio power amplifiers, this is an excellent resource.
Randy Slone begins with the basics of acoustics relating to audio power amplifiers and methodically walks the reader through a variety of designs, ranging from old to new, and simple to complex. As one would expect, much of this information is founded upon well established research. There is also a significant portion devoted to new techniques and principles of amplifier physics which help to de-mystify amplifier operation and provide pathways to improved performance. Unlike many similar textbooks that focus on only one topology or design philosophy, Randy Slone examines the broad range of amplifier configurations and power capabilities, including mirror-image input stages, fully-complementary VA stages, paralleled output stages, and lateral MOSFET designs.
Randy Slone may be somewhat opinionated, but his opinions appear to be logical reflections of measurable facts; and as any good scientist knows, that what cannot be measured does not exist for the world of science and engineering. He makes short shrift of tube cult; these are devices that produce measurable distortion and can never compete with the power capacity of modern solid state systems. The writing style and technical descriptions are easy to follow although a background in electronic fundamentals is helpful. No more than high school algebra is needed. Occasional humor increases the reading pleasure. Randy Slone has the somewhat eccentric habit of discussing current flow as if it traveled from negative to positive pole, while the convention is to describe it moving the other way. Once the reader becomes accustomed to this way of thinking - not too silly for electrons do indeed travel from negative to positive - it becomes easier to read. It is a complete resource for designing and constructing your own high-quality audio power amplifier systems.
I am currently building myself six of Randy Slone's OPTIMOS kits after reading the book. The fact that Randy Slone also sells the kits from his web site is a highly positive feature. Imagine trying to source all those components and make the PCBs yourself. Furthermore, Randy Slone is always available to help with specific questions and suggestion on a one to one basis. He really does answer his e-mail.
Highly recommended.

I can not speak highly enough of this book. If you want to build your own amps, modify an existing amp, or just learn a lot of electronics all related to audio, this book is worth its weight in gold. The author even sells kits, parts, circuit boards, transformers, capacitors, etc. in the back of the book.

Although I am now an electronic engineer, I wasn't when I built my first audio amplifier kits back in the 70's. And although this is not written for someone without any knowledge of electronics, I wish I could have read it 25 years ago when I was just beginning to learn; it would have been more helpful than most classes I've taken.

The author quite systematically and accurately goes through every stage of audio amplifiers, and even talks about the bizarre stuff: the "magical" capacitors, tubes, expensive wire, etc. By the time you're done with this book you can have the best sounding amplifier in town for less money than some people spend on speaker wire, and you'll understand how it works and why.

After reading the book I had a question and I e-mailed the author. He wrote me back a very detailed letter the very next day! Also, this is a big book with 476 pages with high quality print and lots of very clear schematics. Whether you're a weekend hobbyist or an electronic engineer designing audio power amplifiers, you will find immense amounts of extremely valuable information in this book. I can't recommend it high enough.

This book will take you by the hand and put you "in the know" if you are attempting to learn about or construct high power audio amplifiers. Mr Slone is very adept at explaining the necessary concepts in a way that can be easily understood. Anyone with technical ability and a reasonable amount of electronics experience should be able to take this book and build an exceptional amplifier. What I particularly like about the book is it not only tells you the details that you must know, it also tells you why and is very solidly backed up with examples. The book literally covered everything I wanted to know (and then some) about amplifiers. From power supplies to the output stages, he very thouroughly unravels the details that separate the truly great designs from mediocre ones (you may never look at your commercially manufactured amp the same way again!) Designs and artwork are included for 12 different amplifiers, each geared towards different applications- and all sporting exceptional performance numbers. Mr Slone has designed these projects around components that are readily accessible and can actually be ordered at very reasonable prices through his business, Seal Electronics. If you want to build, modify, troubleshoot, or just learn what makes an amplifier tick, then this book is the answer.

For those interested in building power amplifiers, this is an excellent place to learn. Whether you are a beginner or a veteran, this book provides a scientific approach to design and construction without any High-End foolery. While I cannot confirm the authors opinions about amplifier design criteria, he does give explanations why popular concepts are wrong or misguided (some audiophiles might become offended by his blunt statments).

If you are looking for a tool to guide you through the components of amplifier design (all explained in detail with examples), then this is it. I have been building a high quality, audiophile amplifier for the past two years and didn't totally understand how to size the transformer until reading this book.

A beginner course in electronics and an understanding of how transistors work would definately be beneficial, but not mandatory. The design examples and PC board artwork are a huge plus for this book. Highly recommended!

I found the book to be very informative and mercifully it's without the particle physics and electric field theory that tend to drag down many books about solid state electronics.

The author assumes some basic knowlege of electronics on the part of the reader and he also assumes some background in building electronic devices. (In my case, he may have assumed too much!) I liked his sometimes light-hearted approach to the audio electronics business and I thought the book was fairly easy reading. As with many other technical books, I think the reader will get more out of the book if he or she has a project in mind or in progress.

I built one of the more basic amplifier projects from "scratch" using the printed circuit artwork provided in the book. I had a few problems with my project which were my own fault but the author was more than helpful in getting me on the right track through a series of e-mail exchanges. He was truly interested in getting my amplifier to work and the results were amazing to say the least. The amplifier appears to be every bit as good as he says it will be in the book.

Considering the amount of information contained in the book, it's quite a bargain.

My review of this book should be seen in the context of my background.
This book is not "right for everyone." I like dabbling with electronics
kits and a soldering iron. I have never read any book on power amplifiers
before. The only test equipment I own is a digital multimeter. I _loved_
this book.

NOTE: This book is devoted purely to power amplifiers, and that too,
solid state power amps. If the reader does not know the difference
between an integrated amplifier and a power amplifier, he should start
elsewhere.

This book is not for the absolute beginner to electronics. The author
simply assumes you know what a FET, BJT or an opamp is, for instance.
It _is_ possible to extract great value from this book without knowing
about degenerative feedback, for instance, but knowing all this would
help.

The author has strong opinions, something I really enjoyed. I have
always learnt the most from people with strong opinions, provided they
show me how they have arrived at those opinions. Randy Slone's opinions
about valve amps and the "valve sound", for instance, are a must-read.

The author's standards of good performance are superlative. The "good"
designs here are probably comparable to the best amps commercially
available, provided you agree with the author's yardsticks on quality
in a power amp.

This book is well thought through for the amateur constructor. The
author gives you a list of transistors on page 13 which he then
uses in all his designs. His PCB designs are all single-sided,
allowing easy home fabrication, and are a bit sparse, allowing easy
soldering. This sparseness also allows photocopying the PCB layouts
directly to transparent acetate sheets to make the "positive artwork" for
PCB fabrication, without running the risk of errors. There are sections
on the pragmatics of looking for the "low-tech" components like heatsinks,
how to put things together mechanically, eliminating hum and ground loops,
soldering, PCB making, etc.

Chapter 10 is probably the most insightful and interesting chapter of
all, holding the entire book together. It takes the reader through the
actual design of a new amplifier, starting with a set of objectives.
The author goes about plugging pieces into a design, one by one, to
build a no-compromise top-end design, showing the reader at each step
why he chooses each piece.

Chapter 11 is a collection of ready-to-build designs. Most of the 12
designs in it are no-compromise designs. Design 11 is an ultra-high-end
Class A amp rated at 40W into 8 ohms. Design 3 is a bipolar-OPS design
giving second harmonic distortion less than 0.0001%. Design 12 is for
a MOSFET OPS amp with MOSFET-based reliability and a THD of 0.0038%.

The author's writing style is conversational, laced with humour, and easy
to read. Also, this book cannot be read --- it has to be studied. Each
sentence in this book potentially carries a new idea or insight, which may
not be re-visited subsequently. The first time I encountered Kernighan
and Ritchie's "The C Programming Language," I remember feeling that _all_
essential concepts about C (a tough programming language for the beginner)
were stated explicitly in that slim book, if only the reader would read,
think, and absorb _each_ sentence. This book almost
reaches the same levels of richness of content.

Where the book ends, the author's personal interaction begins. Over the
last few months, I've asked dozens of questions to the author on email,
and have been rewarded with insightful and friendly replies each
time. This enormously helps in giving the reader confidence to try his
hand at the designs.

Is this the "perfect" book on audio power amplifiers? Are there flaws?
I'll be nit-picking, but here goes:

1. There are typographical errors in circuit diagrams. They do detract
from the smooth study of the (fairly involved) material. Two Q4's
occur in Figure 4.8a, on page 85, in the very first chapter attempting
any circuit analysis.

2. I would have liked sections which would start with transistor
characteristics and device selection, and then synthesize an input
stage, a VA stage and an OPS from the ground up. In other words,
this book alone is not enough for me to start with an assortment
of transistors and passive components and synthesize my own current
mirror or fully complementary input stage or emitter-follower OPS, for
instance. To be fair, many places do discuss the rationale behind the
value of passive components, but not always, and for a novice like me,
not enough. I'd have liked a Chapter 10 twice its current length.

3. I would have liked a list of substitutes for the transistors the
author uses in his designs. Not all of them are easy to find,
specially where I live.

All in all, I find this a five-star book, and a must for any amateur or
professional amplifier designer or constructor's bookshelf.

This has got to be the single best book I have read on building high-power amplifers! Many other publications do not go into the level of theory that is needed, or, go to the extreme. This book has a nice balance between theory and application. An extra bonus is the pcb artwork is included for several designs in the book (complete with parts placement diagram). G. Randy Slone does a great job of "debunking the myths" of audio amplification; in an almost humorus way! I would not advise a pure electronics beginner get this book, unless they simply want some basic information povided in the early chapters and some complete power-amp designs. There is some discussion requiring basic knowledge of tranistor/mosfet (and the like) theory. G. Randy Slone does indicate that he did not write the book for the pure novice. That being said, I have had only two, very basic, EE classes (about 9 years ago), and I don't have much trouble with the book. :-) I highly encourage anyone who is interested in building and designing power-amps to get this book.

It's become a national obsession, for some reason, to read-or flip through-this book and either praise it to high heaven or declare it better printed on soft, absorbent paper so that it would have some utility in the world. I'm not going to do either one, because it's neither terribly good nor terribly evil.

If you want to cobble up some relatively inexpensive utility grade audio amplifiers at a somewhat lower cost than buying them-trading off your time, any warranty, resale, et al-which, it seems to me, is your right, this book provides schematics, PCB layouts, and enough commentary to get you going. Is that so rotten?

However, it doesn't connect the theory and practice very well. And it does contain a lot of opinion that is biased to some degree (isn't opinion always?) and marginally incorrect statements seemingly calculated to irritate the high end crowd. (Pro recording studios do use a lot of tube equipment, and not for coloration: almost all opera recordings are done on Neumann tube mics, for example.)

I would pick any of Doug Self's books or several others over this one if building these specific amps were not your primary goal. It's a hobby project book, period.

And, as a matter of interest, transistors-bipolar or FET-are not "more neutral" or "accurate" or linear than vacuum tubes. They are (relatively) low impedance devices and they come in N and P flavors, which means no output transformer is needed and therefore more, much more, negative feedback can be used to improve bandwidth and THD measurements. Alas, NFB is a tradeoff and more is not necessarily better-which is what the real pros started figuring out in 1972 (yes, the storied Russ Hamm!) and the 'subjective' backlash started. So, Slone is really being a little disingenuous,and he knows it...but then again, so are the high end tube vendors, because most of them are selling a sizzle that's out of proportion to the steak, and one that's often crudely built beneath the pretty machined front panel at that. Two wrongs don't make a right, but our entire system of commerce is built on the proposition that three lefts do.

This book is an excellent manual for someone who wants to build a power amplifier. If you have experience building electronics you could set out building any of the designs after one read through the book. The 12 designs presented cover applications from musical instrument amps to home and professional audio. General principles of amps are covered with many insights and opinions from the author, however few proofs or evidence of these assertions are provided and it is left to the reader to follow up on the theory and mathematics. Details and guidelines for physical construction are also presented, making this an all-in-one manual for building an amp.

I will be honest in that I have only built two of Slone's amps to this point (a 12 Watt and a Headphone Amplifier), but the performance of them has been very good for the price. I am sure I could go out and spend some money and get equal or better performance but if you are a competent electronics hobbyist you should have no problem matching most expensive amps in terms of performance with a limited budget. Not to mention there is a lot of pride that comes with making your own equipment. This book is well laid out and steps you through the stages of the "standard" Lin topology of audio amplification (Much like Douglas Self and his publications). Mr. Slone goes into good detail on how each stage works and performs but please note you should be familiar with electronics going in, as this is NOT a beginner's book, but rather a book made for those with some experience wanting to expand their knowledge through further experience. This isn't a replacement for a theory based text book, but rather a quick and easy way to dive into building your own amplifiers. If you like what Mr. Slone is saying and would like a little more in depth coverage of his techniques, a Douglas Self book may be in order for you.

To the potential buyer: I highly recommend this book if your interest lies in building relatively inexpensive high quality solid state amplifiers. Randy does not cover other types of amplifiers in this book (valve, chip, etc..). What you should not expect out of this book is a thorough background on electronics. For that you will need other books.

Some of the other reviewers have stated disgust with Randy Slone's bias toward DIY solid state amplifiers. I understand where they are coming from, because at some points in this book you do get the feeling he does not approve of tube based amplifiers or any high end audio equipment. But this is not to say he paints an unfair opinion. I have read this book several times and can't say I was ever taken aback by his claims. But I do think good advice in reading this book for the beginning hobbyist would be to be sure to keep an open mind about many amplifier types and classes. Throughout the book he lets you know that whatever your preference is for sound, you should go for it, but he is definately biased toward solid state (I can't say I blame him, the man built his entire career on solid state devices).

So, in short, this book has very good technical content as well as very good sections on power supply design and general construction techniques (grounding, calculations, etc), in addition to the amplifiers. I enjoyed reading this book a lot, and I feel any serious DIY audio hobbyist should give it some consideration.

I give it a 5 star rating because it is very inexpensive and presents a lot of good information, along with cookie cutter designs you can make. So far I am more than pleased with the amps I have made and this book is well worth the money it costs.