As we both, independently, began to investigate horn speakers in the 1990s, as early as just before the World Wide Web was beginning to happen, it became apparent that there was no single book to consult on the subject. People still exchanged photocopies of papers mailed in envelopes back then, (if not using fax machines) and it was a matter of what libraries and publications one might have access to. Even though today, some 25 years later, much more has been digitized and can be found online or is made more accessible by the use of search engines, online library searches etc. it turns out that a lot of good material on horn speakers continues to remain difficult and time consuming to find. Some is protected by publishers' rights, some must be paid for when you have ultimately tracked it down, and still some has to be studied on site, at libraries or archive institutions. We think that necessarily, since the subject of horn speakers has been so difficult and time consuming to approach in terms of study, most people involved in it today base their activities and understanding upon a limited selection of available theory and complement that with practical experience. We think a more complete treatment of the specific subject of horn speakers has been missing in audio literature and that we're not the only ones to have had that thought.

The subject itself is quite complex and demands a great deal of patience and dedication. As the book is now coming out, we are in the position to state that it provides a fairly complete bibliography on horn speakers and related subjects, and also summarizes most of what has been studied and published on the subject. Some readers may be surprised to find how much more "has been out there" than has been commonly known, even in today's "information age". But we have been digging deep in some places.

We can not expect all readers of the book to go to the depths that we did. However, we think that the comprehensive nature of the book will provide further answers to questions which arise on studying the subject than would have been the case with a more condensed book. We have pieced together theory relevant to horn speakers but have tried not to leave too many "dark corners", so have included essential theory on sound radiation, distortion mechanisms, the auditory system, magnet system design and other topics relevant to components of horn speaker systems and to complete systems. Understanding the nature of compromises and design decisions involved requires consideration of many different problems and mechanisms involved. We have tried to put together a more advanced and complete theory for horn speaker systems than has ever been available to the serious student of the subject.

Gathering and organizing all the material for the book would have been almost unthinkable for two guys to handle on their spare time on a low budget without the use of computers, scanners and digital cameras, sharing pdf files and images using file sharing services etc. In fact much of our research has relied completely on the use of such digital tools, to save time, to deal with the logistics of information gathering, and to be able to collaborate separated by geographical distance. Some may then still wonder why the end result, after 15 years or research, in 2019, is a book, printed on paper. But there are many reasons for this. While technically the book manuscripts have had the important function of tying together a huge number of archived image and text files, we find that reading the book on paper is also a completely different experience than any presentation on a computer screen can offer.

We also love books, and have wanted our work to find its way into libraries and book collections, as a physical document and object for posterity. Very many photos and images in the book are reproduced with permission and under license, and we would not want them to be subject to digital copying. A book demands one's undivided attention more effectively than another window on a computer screen. We think that the complex and demanding subject of the book deserves just this kind of attention. It would have been impossible to research and write it without a great amount of time and patience, and it will also be difficult to read and appreciate without devoting some corresponding time and patience to it. The book is also the result of having read, studied and discussed hundreds and hundreds of papers and files over a long period of time. Time has also worked for us in the realization of the book. It would have been impossible to produce a book like this in a short time. Just don't think of it as a "quick fix" resource, it's certainly more than "a handful".