Frequencies and Instruments

Chapter 1. Physical Sound 1.5 Frequencies and Instruments In the following table, the major music instruments (including vocal chords) are displayed, including their main frequency ranges and some commonly used terminology. (the full color chart is available as bonus content with the purchase of the PDF version of the book!) The first line (Notes) indicates the … Read moreFrequencies and Instruments

Harmonics

Chapter 1. Physical Sound 1.4 Harmonics What is a harmonic? When an instrument is played or a note sang, different frequencies are generated: the fundamental frequency (or fundamental note) and overtones, also called harmonics. The basic reason why this happens is because a vibrating string (attached at both ends) has very precise ways of vibrating to … Read moreHarmonics

Phase and Polarity

Chapter 1. Physical Sound 1.3. Phase and Polarity Polarity and phase are usually confused with each other, but they are not the same. The phase is the initial value of the wave when : it has to do with the time axis of the wave; polarity, on the other hand, has to do with the displacement … Read morePhase and Polarity

Sound Volume

Chapter 1. Physical Sound 1.2. Sound Volume Sound volume is always measured with respect to some reference level and almost never in absolute terms like most other quantities are. Thus, what we think of as “sound volume” is in fact a ratio in sound pressure. The unit measuring sound pressure is the Bel. Because we … Read moreSound Volume

Sound Waves

Chapter 1. Physical Sound 1.1. Sound Waves What are sound waves? Sound waves are air molecules vibrating under the influence of an initial shock: a string being plucked; a drum head being hit. Any movie with loud explosions in outer space should have their technical staff flogged in public: there are no air molecules in … Read moreSound Waves