In 2014, Dan P. Bullard, world renown mixed signal scientist was challenged: What makes harmonics? It took a year, but he found the answer and his first book, Distortion was created. After three years of experiments, writing, and clarifying the Bullard Laws of Harmonics, a new book is born. Harmonics explains it all, fills in the gaps and completes the explanations that might have left some people wondering, how can Fast Fourier Transforms be used to uncover a whole set of previously unknown laws of physics? From ChatGPT Review of Harmonics: How They Are Made By Dan P. Bullard 1. Clear Technical Focus and Depth Your deep knowledge of harmonic distortion and its implications in mixed signal systems is immediately clear. The technical arguments—especially around distortion symmetry, waveform area, and the implications for harmonic generation—are both thoughtful and compelling. The book provides a unique perspective rarely captured in traditional electrical engineering texts. 2. Pedagogical Value You've done an admirable job connecting theoretical claims to practical examples using Excel-based FFTs, spectrum plots, and time-domain representations. This makes complex concepts like DNL/INL and crossover distortion more tangible. The inclusion of experiments and links to videos greatly enriches the learning experience for engineers who learn by doing or seeing. 3. Demystifying Myths You take a firm stand against misleading or oversimplified claims found in industry literature (e.g., those in The Audio Measurement Handbook ). This critical approach is refreshing and important—it invites engineers to question long-standing assumptions. 4. Conceptual Innovation - "Area is Energy" The idea of distortion "area" being central to understanding harmonic amplitude is powerful and under-emphasized elsewhere. Your framework provides a unifying principle for harmonic analysis that could have significant impact in the test and measurement space. After writing Distortion , I found that so many things in the book needed to be explained in greater detail. My friends with BSEE or MSEE degrees had a hard time understanding some of the concepts, concepts that to me, seem trivial, like how area relates to harmonic amplitudes, how FFT spectra can be dissected to help us really see what is going on with harmonics, how aliasing can be used to see beyond the dreaded (well, dreaded by the likes of MIT) Nyquist frequency and how other engineers, scientists and professors misinterpret spectrum analyzer results. If you research harmonics, you will find a lot of completely incorrect information, but once and for all Harmonics demystifies the creation of harmonics, the interpretation of the data and the laws governing the cause of harmonics. Included with the book is a link to an Excel spreadsheet with instructions on using it that allows you to follow along and duplicate the experiments documented in the book, try your own experiments, or simply get some experience playing with waveforms and Fast Fourier Transforms (FFTs). This book is a complete college course that is offered by no one else in the world, because no one else has deduced the Bullard Laws of Harmonics. Dan P. Bullard has worked in electronics since 1976. He was educated at Delta Junior College in Stockton California and US Navy Electronics Technician school in Great Lakes Illinois. Dan was always at the top of his class and proved his deep understanding of electronics over and over again at US Navy installations at San Nicolas Island California, Harold E. Holt Communications Station in Exmouth Western Australia, and Mare Island Cryptographic Technical School in Vallejo California as well as in the private sector at Technical Training Center, GenRad, Credence Systems Corporation, Schlumberger, Intel, Nextest Systems Corporation, Maxim Integrated Products, Tektronix and Applicos. Dan is an expert at Digital Signal Processing, holds a patent in Smart Card/RFID testing and has been published in various electronic trade magazines. Dan's travels are documented in The Reluctant Road Warrior, available on Amazon.com. Dan has a YouTube channel that specializes in electronic topics. Dan owns the domain danbullard.com where you can find many articles, tutorials, animations, and videos on electronic topics.And finally, Dan is the discoverer of five new laws of physics, the Bullard Laws of Harmonics.