Rating: 
Summary: Twaddle, stuff, and nonsense
Review: Basically this whole book is the effort of a hayseed electronics vendor to peddle his own kits of plain vanilla grade stereo equipment. With skilled electronic assemblers in America getting $8.30/hr (and equally skilled Asians getting that per day!) and components in hobby quantities bringing a 50 to 500 percent premium over what commercial buyers pay even in 100 piece quantities, he claims a hobbyist can better commercial grade designs in his hobby workshop cheaper.
This reminds me of Fred Willard's character in the excellent film, "A Mighty Wind". One of his catchphrases-"I Don't Think So!"-applies here.
These amp designs, apparently mostly from Douglas Self's books, are nothing special or unique: as someone else pointed out, if they were, there would be dozens of amplifiers of "Slone type" sold ,just as many companies made "Williamson style" amplifiers, without compensating DTN Williamson, during the early postwar hi-fi era.
About the only justification for homebrewing audio amps is to get a design offered commercially only as a "high end" piece at huge expense (and gross margin) or not at all. You can get an education, perhaps, but a breadboard project of a couple watts can give you that, and besides, audio amp design isn't exactly in big demand: the websites of High End, pro, and mainstream audio equipment manufacturers list continuing job vacancies for DSP software engineers but never analog designers.
Rating: 
Summary: Low end sound reinforcement mentality
Review: I think Mr Slone is basically an electronics nerd who hates High End audio because it costs money and involves people who are trendy and fashionable and often buy it for pristege.
At hamfests and swap meets, you meet these guys all the time.I have been building High End audio equipment and restoring vintage pieces for thirty years. I still go to these affairs, but the good stuff is almost all gone, except for test equipment, and even that's getting lean.
He's completely wrong about just about everything when it comes to the serious home reproduction of quality music-music with real dynamic range and bandwidth. They are also twenty or so years out of phase with serious studio listening-mixdown and mastering in the best studios and mastering facilities. They do, however, make sense in the world of sound reinforcement in clubs, houses of worship (HOW, in audio-contractor-speak) and for musical instruments except electric guitar. These are high duty cycle applications where considerations important in high end domestic service don't matter.
He talks smack about many things that have unquestionably proven good in high end audio-autoformer-coupled outputs, linear regulated rails, and Class AB operation-and makes snotty and spiteful comments about tube equipment rather than looking at the real issue-how is it that equipment that measures so bad _in some cases_ can give such good sonic results? And in fact, some of the tube equipment out there measures very, very well.
The designs in this book probably will work fine if you really want to build one, although I'm sure they are not his original work except in detail. So I can't condemn the book completely. But they are not terribly good for home listening unless you have really inefficient, but benignly load-presenting speakers and play music with limited dynamic range or at high SPL all the time. If that's what you like, fine, but you are wasting your money on high end equipment anyway: inexpensive PA gear will do as well.
Rating:
Summary: Mid-fi with little explanation
Review: This is an extension of Slone's earlier book and it is a little better, but not a lot. He reiterates everything he said earlier-ranging from opinion to nonsense-and then as before launches into his pet designs with little good explanation.
If you want to build a Class B semi-serious amplifier for instrument or PA or non-serious-listening use this will probably work, although there are a lot of old 70s and 80s designs readily available at your local library in old electronics and audio magazines.
If understanding the trends in serious audio work today is your goal, start with the "horses mouth" JAES paper "Tubes vs. Transistors: Is There A Difference?". This was hugely important because it was the first published paper in professional reviewed circles that addressed the possibility that traditional metrics such as THD,frequency range, and S/N might not fully address problems in professional audio.
Rating:
Summary: Tubes rule. Slone drools.
Review: A good deal of this book is an attack on esoteric audio in general and vacuum tube equipment in particular. But just because Mr. Slone hates tubes (and he does, although he can't be honest with himself, like most fundies, and so has to attempt to disguise his real motives) doesn't change reality. Measurements aside, all other things being equal, tube equipment generally sounds better.
If you listen to good music at normal volume, in a normal house, the average power output of your amplifier is almost always between 10 and 500 milliwatts. You can prove this with a DMM that has at least a 20 kHz AC bandwidth and peak and averaging functions hooked across your speaker. The Class B Lin topology solid state amplifier with large amounts of global NFB, which Slone describes and advocates to the exclusion of all others, does very well at between 5 and 100 percent of its rated power, but is terrible at between .01 and 1 to 2 percent of rated power.
There are various circuits to work around the problem, but Slone ignores them. When you refuse to accept the problem, you can't be part of the solution.
There are several possible solutions. One is the venerable transformer coupled vacuum tube amplifier, which for all its technical flaws, does reproduce music beautifully. There are modern tube amps that are universally acknowledged to sound great, have long tube life (in the tens of thousands of hours) and have distortion measurements in the same class as most solid state amplifiers. There are also solid state amplifiers that use innovative circuits and careful device matching-semiconductors are inherently much more variable in device parameters than tubes, which Slone conveniently forgets to tell you-to "give good first watt" while still providing peak power reserves traditionally associated with solid state designs.
I have heard an amplifier built to Slone's schematic on Slone's PCBs-in fact I set it up on my company's distortion analyzer after hours-and it meets his published specs fully. Hooked to my Klipsch LaScalas it has all the sonic elegance of a Peavey CS-400 I happened to have on hand-it makes Blossom Dearie sound suspiciously like Louis Armstrong on her quietest passages, and Angel Romero sounds like Dick Dale is doubling up on his thumb lines in the distance.
Rating: 
Summary: M. A. Thompson
Review: After reading Mr. Slone's earlier textbook, entitled "High-Power Audio Amplifier Construction Manual," it is obvious to me that he intended this book to be targeted toward the do-it-yourself audience. Its coverage of audio system construction is extremely broad, including preamplifiers, headphone amplifiers, filters, tone controls, power amplifiers, protection circuits, power supplies, and a great deal of associated topics. As in the case of his aforementioned book, the focus is on 'high-end' solid-state systems, but there is much less coverage of engineering material in preference to practical construction information. Thus, this book is probably a much better choice for the audiophile hobbyist who simply desires to build and understand the operation of audio projects, in contrast to those engineering types who want to custom design systems down to the component level. Mr. Slone has an exceptional talent for explaining complex subjects in simplistic language, so I would definitely recommend this book for novice audiophiles or those hobbyists with little practical experience.
There are 80 projects detailed in the book, ranging from simple to complex, and typically in a 'good, better, and best' sequence. The PC board artwork and layout information for some of the more complex designs are provided in Appendix C. For the weekend audiophile hobbyist, there is probably years worth of project choices. Of particular interest is Mr. Slone's Fig. 6-21 L-MOSFET amplifier design (which he calls the OPTI-MOS design on his website). These amplifier kits have been sold commercially for about 5 years, and according to the various audio message forums, they have been very well received. Personally, I think the OPTI-MOS amplifiers are the best performing amplifiers that I have ever listened to, regardless of price.
Mr. Slone has standardized all of his designs around a relatively small number of component types, which is not only convenient, but also saves a significant amount of materials costs. Consequently, with a minimal inventory, almost any project in the book can be constructed. The only criticism I have is that Mr. Slone did not include any detailed parts lists for the projects, so it takes a little time to go through the schematics to obtain a materials listing for ordering purposes.
In general, I have to rate this book as an excellent resource to anyone who has more than a passing interest in audio electronics. It is far more comprehensive and accurate than most other textbooks on the same topic, and it is two or three times less expensive than the majority of its competition.
Rating:
Summary: Lovely coverage of top-end DIY analog audio
Review: First, my background as a reviewer. I love listening to music, and I like
dabbling with electronics kits and a soldering iron. I have an engineering
education, but I understand the bare minimum basic electronics. And the
only test equipment I own is a digital multimeter. My review of this book
should be seen in the context of my background. This book is not "right
for everyone;" you need to know at least as much basic electronics as
I do. Another contextual factor is that this book is only one part of
"what you get." What you also get is the author's constant email-based
guidance, and his Website from where you can buy PCBs and components.The author assumes you know what a transistor or an opamp is, for
instance. The book also expects you to have _built_ some circuits
before. The book discusses many opamp-based circuits, all the time
expecting that you can recognize an opamp-based unity-gain inverting
buffer when you see one. It _never_ gives you IC pinouts of the
ICs it uses in its circuits. The author has strong opinions, something I really value. I've 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
potentiometers and tone controls in preamplifiers (pages 77 to 80),
or on "valve sound" on page 126, are worth passing around to all
brand-conscious audiophiles with more money than good sense (plenty
of them around). The book's standards of good performance are superlative, i.e. the "good"
designs here are probably comparable to the best designs commercially
available, in terms of raw audio quality. The author comes from the Scientific School of Audio System Performance
Analysis (SSoASPA). He believes that if two amps with similar specs sound
different, it doesn't indicate the presence of subjective, unmeasurable
attributes --- it merely means that we are not performing the right tests
for the right parameters. The author's writing style is conversational, laced with humour, and easy
to read. From page 49: "Some audiopiles ... believe the least number of
components (and the greatest percentage of gold plating) in the signal
path will ultimately provide the highest quality of undiluted sonics." I'll touch upon a few specific chapters --- the reader can always
get the actual Table of Contents from Amazon's Webpage. Chapter 2,
"Beginning at the beginning", focuses on balanced to unbalanced signal
connections, and then discusses stepped attenuators. Both these are
among the latest "purist" fads, with questionable benefits in most
cases. The chapter concludes with an ultra-brief discussion on digitally
controlled potentiometers. Chapter 5 is a short chapter dedicated to
headphone amplifiers, both opamp-based and fully discrete. Chapter 6
is a long chapter on power amplifiers, with some very high-performance
ready-to-build designs. Chapter 10, "General construction information,"
is an excellent coverage of hum, grounding, and such other obscure issues
which often ruin the performance of actual amps built from flawless
circuit designs. The other sections of the chapter covers PCB fabrication
and heatsinks. Where the book ends, the author's personal interaction begins. Over
the last few months, I've asked the author dozens of questions, and
have been rewarded with insightful, courteous, and friendly replies
each time. This follow-up "service" from someone so knowledgeable adds
enormously to the value of the book. Could I have asked for anything more from a book which wants to cover
all aspects of the audio home-building scene? 1. The book does not touch even the "D" of digital audio. The issue of a
super-stable clock alone is worthy of a few circuits and a
fair amount of experimentation; Randy Slone's no-nonsense fad-busting
exploratory style would have suited it well. The amateur constructor might need DACs, ADCs, sampling rate
converters, digital audio level meters, an input selection circuit
for switching among digital inputs, or an SCMS copy-bit modifier.
The absence of digital audio is the biggest gap in the book. 2. There are no super-quiet high-gain signal amplifier circuits
of the kind needed for MC turntable cartridges. A good pre-preamp amplifying
sub-milliVolt signals would have plugged a gap for vinyl lovers on
a budget. 3. Cabinet construction, front panel design and building, fitting of
jacks and connectors, selection of passive components like reed
relays and rotary switches, etc, all have subtle issues. A better
coverage of these issues would have been very useful. 4. Some circuits for testing audio equipment, e.g. a sine wave generator,
a high-Q notch filter for harmonic distortion analysis, a capacitor
meter, etc., would have been useful. 5. I would have liked an entire chapter devoted to control circuits for
controlling the controls of a preamp, e.g. the input selection,
volume, balance controls, etc. Designing very low-noise,
low-distortion solid-state signal switches and super-clean electronic
potentiometers is tricky. All said and done, would I buy this book again, knowing all these gaps?
Answer: YES! In fact, I'm buying a couple of copies to gift to friends. All in all, an excellent book, and a must for any amateur or professional
designing or building audio systems. And if Randy Slone chooses to write
the "Audiophile's Digital Audio and Controls Projects Sourcebook" someday,
I'll be waiting, cheque in hand!
Rating:
Summary: Amplifiers and More
Review: I bought this book after my great experience with Slone's High Power Audio Amplifier Construction Manual. This is a fantastic book if you want to build your own amplifier "accessories", such as headphone amps, preamps, equalizers, and other types of signal processing devices. There is an interesting circuit for a phase-linear filter, which I built and works beautifully. It splits the audio signal up between the pre-amp and power amp into low, midrange, and high frequency spectrums. This avoids the phase shifts associated with conventional speaker crossover networks.
You'll need a power amp for each frequency spectrum, but that's no problem. You'll have so much fun building your own amps that you'll have plenty of them laying around. The resulting sound is absolutely fantastic.
Rating:
Summary: I built my own amplifiers using this book and...
Review: I found the entire experience to be fantastic. Using Randy's books I built two OPTI-Mos designs from the ground up using only the books and a little email advice from Randy. I consider myself to be an audiophile and the two 200W mono block amplifiers I built based on Randy's topology sound as good as any B-class amplifier I've ever listened to. And that includes amplifiers costing up to as much as [a lot of money]. I honestly did not expect that to be the case. Randy, was great help both on the phone and via e-mail when I experienced difficulties. You can also buy kits through his website if you are not confident with designing your own amplifiers from the ground up. I highly recommend this book to any one who wants to experience premier audio quality on a fixed budget. Note that the book concentrates primarily on signal processing equipment between the source and the speakers. There are many designs for Amplifiers, Preamplifiers, Tone Controls, Equalizers, etc... But there isn't really anything on how to build CD players or other source equipment. If Mr. Sloane ever publishes such a book. I will most certainly absolutely buy it.
Rating:
Summary: I built my own amplifiers using this book and...
Review: I found the entire experience to be fantastic. Using Randy's books I built two OPTI-Mos designs from the ground up using only the books and a little email advice from Randy. I consider myself to be an audiophile and the two 200W mono block amplifiers I built based on Randy's topology sound as good as any B-class amplifier I've ever listened to. And that includes amplifiers costing up to as much as [a lot of money]. I honestly did not expect that to be the case. Randy, was great help both on the phone and via e-mail when I experienced difficulties. You can also buy kits through his website if you are not confident with designing your own amplifiers from the ground up. I highly recommend this book to any one who wants to experience premier audio quality on a fixed budget. Note that the book concentrates primarily on signal processing equipment between the source and the speakers. There are many designs for Amplifiers, Preamplifiers, Tone Controls, Equalizers, etc... But there isn't really anything on how to build CD players or other source equipment. If Mr. Sloane ever publishes such a book. I will most certainly absolutely buy it.
Rating:
Summary: A great DIY audio publication
Review: I have purchased three books by Randy Slone and have found all of them to be fascinating reading. Even though I am a novice with respect to amplifier design and construction, I feel that I will now be able to attempt one of the designs in the books. I did read all three of the books a few times though before feeling competent. Some of the technical books I have read are way over the top for a novice like me, these are not. Although I have not spoken with Randy Slone personally, I have sent a few E-mail messages. Randy has always responded and is keen to give any further information.
If you are not sure what a resistor colour code is you may need to do some more reading/research before wading in at the deep end.
In summary .... Easy to understand, good overview of the basics/advanced, nice construction tips, diagnostics (important) and some circuits at the end of the books to keep you amused.
You could end up with a nice high quality amp and have saved money as well !!
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