In a previous Booknook Blog post, I told you about a book, The Half Life Of Facts that explains that facts change so quickly, a doctor who graduates today has 10 year old facts in his brain that are all wrong by now. I've been reminded of this effect again and again. Facts don't last long in our world, since much of the previous world was based on ridiculous fabrications that, we now know are completely wrong. Two years ago I wrote a book called Distortion: The Cause of Harmonics and the Lie of THD. Recently I released a second edition, and shortly afterwards got my best review so far (5 stars). The book came about because I made a video chastising my client's competitor for an incorrect supposition in his book regarding harmonics and where they come from. I was challenged on my video and forced to defend myself, Distortion was my defense.
As it turns out, the mistake made in the book I was critical of is not alone in using fantasy to explain how harmonics are created from distortion. At the recent holiday book sale, I found another book on electronics, looked in the index for "harmonics," found the entry and read it. I burst out laughing, complete idiocy! Here is just a snippet.
"For example, theoretically speaking, a square wave contains all harmonics, but predominantly, odd harmonics"
Sounds reasonable, right? No, it's not. As my book points out, a square wave consists of harmonics based on a simple formula where the only variable is duty cycle. Duty cycle defines how much of the wave is high divided by the entire wavelength. A 50% duty square wave is high half the time, and low half the time, and has ONLY odd harmonics. Clearly the writer of the book never actually looked at a square wave or a spectrum of one, he was just making it up! Shouldn't we be allowed to point out mistakes in other people's books?
As it turns out, the mistake made in the book I was critical of is not alone in using fantasy to explain how harmonics are created from distortion. At the recent holiday book sale, I found another book on electronics, looked in the index for "harmonics," found the entry and read it. I burst out laughing, complete idiocy! Here is just a snippet.
"For example, theoretically speaking, a square wave contains all harmonics, but predominantly, odd harmonics"
Sounds reasonable, right? No, it's not. As my book points out, a square wave consists of harmonics based on a simple formula where the only variable is duty cycle. Duty cycle defines how much of the wave is high divided by the entire wavelength. A 50% duty square wave is high half the time, and low half the time, and has ONLY odd harmonics. Clearly the writer of the book never actually looked at a square wave or a spectrum of one, he was just making it up! Shouldn't we be allowed to point out mistakes in other people's books?
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