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- Veröffentlicht auf Amazon.com
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
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
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!