[MUSIC] Our class video showed us how it came about that we in the west have a seven pitch or seven note scale. It was given to us by the ancient Greeks, owing to their love for mathematically pure musical intervals. They used math to explain the entire universe, including music. The Greeks had several different kinds of scales, and you heard all their funny names there in the class video. And this held true for about 2,000 years. But by the 17th century, Western musicians had reduced these down to just two kinds of seven pitch patterns, a major pattern and a minor pattern. The major pattern went this way. [MUSIC] And the minor this way. [MUSIC] Each follows a particular pattern of steps on the keyboard. You can look all this up in your textbook to see what the two patterns are. Whole and half steps. The smallest distances on the keyboard. But the important thing is to hear the keyboard. And hear the major and minor when played on the keyboard. [MUSIC] Major. [MUSIC] Ever notice on a piano that we have two pitches that sound rather identical? Almost, [MUSIC] The same thing. [MUSIC] If we start on this pitch. [MUSIC] Go up and down the scale, we get that arrangement. If we start here, [MUSIC] A-B-C-D-E-F-G-H. No we don't have Hs. Why don't we have Hs? [MUSIC] A-B-C-D-E-F-G. Because this is duplicating, in essence, the one down below. Octave duplication. [MUSIC] The eighth note is the same as the first. Therefore the eighth note's simply called the octave. You know about octaves. You've been hearing them all of your life. I'm gonna sing a pitch. And you're going to sing the octave above. I'll do one first and then you do one. I'll take this. [SOUND] Okay, now you do one. [MUSIC] There we go. [MUSIC] That's right. [SOUND] So we have the octave in our ear. This is the two to one ratio that we discussed before, in our first session. The upper pitch, the octave above is vibrating. My vocal chords here are vibrating twice as fast. [SOUND] As the lower octave. [SOUND] The eighth pitch of the scale duplicates the first pitch. Eight and one are the same and thereafter all of the intervals are the same. [MUSIC] The intervals In that higher octave that I just played are exactly the same as the lower one. For this reason we have only seven letter names in the scale. A-B-C-D-E-F-G, no, H-I-J-K-L-M-N-O-P, because we start all over again. This is the phenomenon of octave duplication. And it is part of nature not nurture. Octave duplication is at work in musical cultures around the globe. Whether in Chinese music, Indian music, Indonesian music or African music. So we in the west have a major scale pattern and a minor scale pattern, each with seven different pitches. But the distance between the adjacent pitches in those two scales is not the same. The major and minor scales involve two different sequences of intervals. Again, an interval of music is simply the distance from one pitch to another. In each major and minor scale there are five adjacent intervals that we call whole tones and two intervals of half tones or half steps. Think of the scale as a ladder with rungs, but as you go up the ladder five of the rungs are a foot apart and two rungs are just six inches apart. So here are our ladders and they're irregular. But if they are irregular blame the ancient Greeks who put mathematics ahead of symmetry. Why is this important? This whole and half step business? This idea of rungs of different sizes within the scale? Well, it's because of the position of the half steps within the scale that makes the major scale sound the way it does and makes the minor scale sound the way it does. Here is the beginning of the major scale ladder. [MUSIC] And here's the beginning of the minor scale ladder. [MUSIC] All major scales sound the same way because they have the same pattern of whole and half steps. All minor scales sound the same way for the same reason. We can begin a major scale, or a minor scale, on any pitch of the keyboard. We can move the pattern, transpose the pattern, as it is called, to begin on another pitch. [MUSIC] Scales are extremely important when listening to music. Far more so than we realize. We've grown up with scales. Even if you've never had a moment of instruction in music theory and you've never heard of the idea of major scale before today, I could prove to you that know a great deal, a lot, about scales because you've been hearing them all your life. So I'm gonna begin to play here, and you finish off a major scale. So here we go. La, la, la, la, la, la. See there? Good. You did it.
