Where do harmonics come from? Distortion, right? But how? What creates harmonics? What kind of distortion causes which harmonics? Is there any way to reconcile a good THD spec but poor quality sound? Is THD, a specification derived in the 1950s, really the right way to assign a stamp of quality to an electronic product designed and produced 60 years later? This book answers all those questions to show that your professors lied to you. They had no answer to the question of where harmonics come from other than "distortion." Filled with new information using the latest techniques in Digital Signal Processing and new, low noise instrumentation, and filled with hyperlinks to videos proving its case, this book breaks new ground in proving that harmonic distortion can be explained by one simple formula.