Testing Loudspeakers

This is a very solid introduction into the science/art of measuring loudspeaker performance and obtaining small signal Thiele-Small parameters. Probably not well suited to the reader w/o some background in engineering mathematics. Such readers may be better served by more of a cookbook approach as there is plenty of math and graphs on these pages, though none requiring more than solid pre-algebra level of ability.From a novice DIY perspective, my one wish is that there were more commentary about designing loudspeakers instead of simply measuring them. Dr. D'Appolito has designed many critically acclaimed loudspeakers for more than one manufacturer (Usher and Focal come to mind) and a case study or two would of added much IMO. Still a very worthwhile purchase that reviews T-S parameter acquisition, MLSSA and some basics of digital signal processing theory. Especially informative were the case studies where he shares several projects he has measured and the insights into performance gleaned is invaluable. Its a keeper for the reference shelf. Wish there were a second edition. BTW there are some more recent articles of Dr. D's on the net summarizing some of his thoughts on speaker design if interested.

This book is an important resource on speaker building and testing, which makes me wonder why its print quality is so bad. Everything is extremely small. Some figures simply cannot be read due to the blurriness of the print. If that wasn't enough, it's like the printers were trying to save ink with grayish print.

Old but good.

Very solid book, nicely written. Good explanations for a difficult topic. Also consider the "Loudspeaker Design Cookbook"; it is reference in this text.

It's nice to see this classic text available again at a reasonable price (I'd paid over $200 for my used copy someyears ago). D'Appolito is a superstar in the world of audio engineering (Google "D'Appolito array") and his writing here is clear, authoritative, and, frankly, the definitive statement on the topic of speaker testing.But remember, though, as one other poster notes, that this is not a layperson's casual read. You'll need at least a basic understanding of loudspeaker design to get the full advantage. If you've taken a college entry-level physics course, you can probably parse most of the text, but it helps to have a little quantitative background in audio engineering.Nonetheless, even if you don't have a math background sufficient to follow the derivations, even self-taught hobbyists and audiophiles may still benefit from Joe's conclusions and observations. After all, reading this book is like sitting at the feet of the Master.

As a matter of fact, it is the only book I have found on testing loudspeakers. Ater presenting the basics of the T/S Parameters theory to some extent, the author presents the relative measurement techniques deeply enough. In general the most interesting topics concernig loudspeaker testing are covered adequately. The theoritical background is also included and presented in simple and absolutely comprehensible language. It is a must-have companion for the very popular "Loudspeaker Disign Cookbook" by Vance Dickason. In a few words I was overall satisfied.

I recently bought "Testing Loudspeakers" by Joseph D'Appolito thinking I would be able to test my collection of vintage hi-fi speakers but the book is so technical it way over my head and is not the right book if you don't have a Masters Degree in Electrical Engineering (my Master's is in Education University of Colorado 1995). The author J. D'Appolito even tells you in his book to first read Loudspeaker Design Cookbook and understand what's going on. Why didn't anyone tell me this before I wasted my money? If you are thinking you are going to learn how to test your home audio speakers with this book and you are a beginner like me, good luck. I thought I was buying a book that would tell me in simple language how to test my speakers, but it goes into complicate math, electronic and theory etc. And to add insult to injury it doesn't even get into crossover networks. You have got to be kidding me. Again the author tells you to go buy another book if you want to know about crossovers. This book is for the professional sound engineer with a degree in electronics.

This book realy clear any doubts about loudspeakers analysis, and is very helpful to any entusiast or sound's engineer.Excelent Choice! Excelent Learning!

From the rear cover to the initial onset a page in, Testing Loudspeakers takes a somewhat unexpected stance by trumpeting Mr.D’Appolito’s status as a loudspeaker designer. Every opportunity has been taken to inundate the reader such that he/she will not soon forget the author has a Ph.D and is a member of the Audio Engineering Society (AES). For those unfamiliar with the AES, the Audio Engineering Society is a self-congratulating social club for those of whom consider themselves authorities on audio. To join their club you must first have a university degree and be important, this is made clear when attempting to join their ranks, via the AES website. The Audio Engineering Society has succeeded once again in demonstrating it is a snobbish tea and crumpet luncheon for rich, self-appointed "experts" whom consider their voice a resounded sovereign note of enlightenment. The whole sorry, tawdry affair comes across as disingenuous, condescending and conceited during the book's introduction. This was not expected from Joseph D’Appolito.For the rest of us unwashed masses, we’ll contend that between the book’s mental floss it may eventually provide useful information that lower lifeforms like myself may use to comprehensively test some loudspeakers.After thoroughly rinsing my hands and having run my cerebrum over a cheese grater to purge flashback images of the first few pages, "Testing Loudspeakers" progressed beyond the tabloid editorialism and went on to introduce this reader to the body of the book itself. It did this by explaining the content of each chapter in serial order. The chapters themselves provide a mix of pragmatic explanations of electroacoustic principles and testing procedures, along with sparse algebra.Some topics could have used a bit more explaining and larger images that single-column print would otherwise affords, but the reader will find themselves able to measure impedance and frequency response using inexpensive tools rather quickly. Later, the author focused on computerized measurement systems, namely the DAAS measurement system, unfortunately one tool few people will afford. This is where things get a little troubled.It reminded me of the AudioXpress article “Testing Loudspeakers: Which Measurements Matter, Part 1” also by Joseph D’Appolito. In that article, D’Appolito went on to claim that "CSD resolution at low frequencies could be improved by plotting the CSD in units of periods instead of time, you see that the decay plot is independent of frequency and only a function of Q” and that this could be called PCSD. He then furthered the statement with algebraic expressions, but apart from “f” which was in Hertz, “t” for time and “Q” for resonance quality, the author failed to explain what denominations other units in the equations should be. The tactless ‘faux pas’ rendered the entire mathematical effort completely useless to the audio community and this reader.From there, he explained the DAAS measurement software “computes the PCSD directly in the frequency domain using sine wave tone bursts as the input signal. The PCSD is generated by exciting the loudspeaker with a sequence of pulsed sine waves”. Again, this isn’t useful. Joseph D’Appolito states his book is for technicians and audio hobbyists, but what he has stated requires knowledge of software design to make this useful for anyone else’s measurement system.In the next section covering Diffraction Responses he showed that it was possible to “analyze diffraction and reflections in general. This can be done by computing the power cepstrum. Formerly, the cepstrum is the inverse Fourier Transform of the logarithm of the complex frequency response…identify diffraction and reflections by computing the power cepstrum”.Microsoft Office Word doesn’t recognise the term “cepstrum” so this reader’s Kayak is drifting to sea, so to speak. Help me, Joseph. Alas there may be hope. Joseph D’Appolito explained this could be done as follows: ”If you take the logarithm of the frequency response, the products break apart into sums. The transforms of the delayed impulse responses have large linear phase components which transform back as a time shift in the time domain. So we get the initial log impulse response plus delayed (and possibly distorted) replicas of the log impulse response in the cepstrum.”Well, let's be honest. That is not the answer I expected from Joseph and it's so cryptic that I’m not certain how anyone will benefit from it. In the book, Testing Loudspeakers, a similar thing happened in a later chapter when flipping through. It’s bad dejavu. While the bullet found may appear shiny, I don't think it's made of silver.I haven’t finished reading the book, because I loaned it to a friend who worked in engineering at Bell for 35 years. He’s had the book for a week or two (it’s Sept 14 2018 right now). When I inquired how far he had read it I learned he closed the book after the first two pages where the author grandstands about his Ph.D and membership with the AES allstar masquerade.My take is the editor and author spent more time on the invention of abstract nomenclature and the literary fashion elements than actual performance enhancements for readers to advance their testing quality. Do I recommend this book? Well, I’ll answer it the best I can, giving the readers 3 options.Option #1: One can find everything pertinent to loudspeaker design and testing on the internet. One needs not spend any money on books to learn up to date engineering practices. The problem is, if one chooses this path they will embark a long journey wadding through forums, advertisements, incomplete algebra and grumpy old men on DIY groups all perpetuating an incredible mixture of incorrect information and conditional truths. My experience watching others has taught me that the majority of people ignore advice from engineering professionals and almost always follow dubious advocacy from “forum experts” and sales people who accrued their advice from glossing eye candy audio magazines edited by practitioners of pure fiction. This applies to both objective and subjective audiophile groups. From experience, the process of telling truth from fiction is 10 years long with minimum 30 hours/week internet usage. In other words, a full time job. The lay person doesn’t necessarily know which testing parameters/electroacoustic behaviors to search for, and other people will take advantage of this to indoctrinate them into their belief system. Behold, the Gateway to Almost Certain Disappointment.Option #2: Testing Loudspeakers by Joseph D’Appolito brings essentially all the pertinent information together in one place for a nominal price. One can sidestep most of the pain and suffering their fellow enthusiasts will endure in the wild. Simply ignore the silly nomenclature and grandstanding portions of the book. Behold, the pathway to Possible Enticement.Option #3: Joining the Freemasons is a great alternative to the Audio Engineering Society. You get thousands of years of proven engineering knowledge; real standards; peer support; and a better looking bumper sticker. Behold, the Passageway to Enlightenment.My own conclusion is I like options 2 and 3. My money has been well spent on this book and I now wear a cool pin. I wish I found something like it a decade ago. It cuts through the mustard and gets right to the points that mostly matter. Will you get an honorary Ph.D when you finish reading it? No. Does this matter? Not unless you want to join the AES. You need a bit of background in design & acoustics beforehand to read the book.I also recommend Designing High Performance Loudspeakers by Martin Colloms and The Master Handbook of Acoustics by F. Alton Everest, Ken C Pohlmann. About me: Ten years electronics and communication engineering experience. I will poke holes in weak arguments, false assertions and wobbly logic to set them straight...so if you bring it, bring it hard.

J'apprécie le contenu de cet ouvrage qui vaut 5 étoiles. Cependant l'impression réalisée par Amazon est d'une qualité insuffisante. Le livre contient de nombreuses figures qui deviennent difficilement lisibles.