Good Vibrations: The Physics of Music

Epilogue

Epilogue Well, we’ve come to the end of the book, so let’s look back over what we have learned. I trust, of course, that you have learned something. First of all, we’ve seen that there is, indeed, an intricate connection between physics and music, and it goes deeper than you might have thought. From a simple point of view, music is sound, and sound is an important branch of physics, but the connection actually goes much further than that. I hope you have come to realize that as you read the book. If your primary interest is physics, you may have been surprised that music is tied to physics in so many different ways. If, on the other hand, you are a musician, with only a peripheral interest in physics, I’m hoping you found some insight into and appreciation of the fundamental role physics plays in music. I also have to include mathematics here, as we saw that the notes of scales and chords obey an important mathematical relationship. We began by looking at the relationship between sound and music. In particular, we looked at many of the properties of sound such as loudness (intensity), frequency (pitch), and the fact that sound, and therefore music, is a wave and has wave properties. We also looked at the concepts of interference, reflection, and refraction of sound waves, all of which are important in the study of acoustics. We saw how musical scales are set up and looked at several types of scales. Besides the usual diatonic scale, two that are of particular interest to musicians are the pentatonic and blues scales. Furthermore , we saw how notes are brought together into chords, discussed various types of chords and chord sequences, and learned how and why they are important in music. As I’m sure you knew before you read the book, music comes in many different genres, ranging from rock and roll, pop, country, through jazz to classical. In chapter 7 I surveyed most of the main types and discussed briefly how they differ. I hope I didn’t miss your favorite. From there we went on to a survey of the various musical instruments , beginning with the piano. In each case I showed how the instrument worked and ended the chapter with a brief survey of some of the virtuosos on the instrument. Included in this survey were the piano, the stringed instruments (the violin, in particular), the brass instruments (including the trumpet and trombone), and the woodwinds (including the clarinet and saxophone). Finally I talked about the voice. It may not be an instrument in the usual sense, but it certainly plays a central role in music. Modern music has become increasingly electronic in recent years, and the book would not have been complete without a discussion of electronic music. Electronic music has had a large impact on the music industry in recent years. Of particular interest in this regard is MIDI, which as we saw, is important not only to professional musicians but also to amateurs. We finished up with a chapter on acoustics, which showed how we can measure the acoustics, not only of large concert halls, but also of small music studios. So that’s it. But wait! What about some of the other things that have influenced the music industry in the last few years? There are, indeed , several, and two of the most important are iPods and MP3 files (and of course I have to include the Internet here, since it is closely associated with both of the above). No, I didn’t forget about them, and so we will briefly discuss both of them in the next two sections. iPods The iPod, whose familiar image you see in figure 123, is one of the major ways that people now listen to music. To give you some idea of how influential (and important) iPods have become, consider the 260 Good Vibrations following: as I write, 100 million iPods have been sold since their introduction in 2001. That’s not a number to scoff at. More people may now be listening to music on iPods than on radios. iPods were introduced by Apple Computer in October 2001. At first it may have seemed that they were just another digital audio player, but what surprised everyone was that they had a 5-GB (gigabyte ) hard drive...