Coursera – FoMT Week 1 / Video 5
The 5th video for Week 1 of Fundamentals of Music Theory is called “Introduction to chords“. Its about 9 1/2 mins long. Dr. Worth begins the session by explaining that with scales so far, we’ve been working sequentially, in a linear fashion, sounding one note at a time. However, its very common in music to sound multiple notes at the same time. This sounding of several notes together is called playing a chord.
My understanding of chords is that they’re the odd-numbered notes in a scale. So, if a scale has 8 notes, the chord tones are the 1, 3, 5 and 7. People also include the 8 because its the octave, making it the same as the 1. The even-numbered notes are notes in the scale, but aren’t chord tones. Also, these odd and even numbers are called scale degrees. So, the first note is the 1, the second note is the 2, and so on. I believe they also call this the Nashville Number System.
Dr. Moir jumps in to say that before we continue, we must recap the difference between the C major scale and the A Aeolian mode, or Natural Minor scale. So, C major is played using the notes C-D-E-F-G-A-B-C. That’s fairly straightforward. A Aeolian is built by playing the notes of the C major scale starting at the 6th scale degree, or the note A. So, its A-B-C-D-E-F-G-A.
The Dr.’s then proceed to play both scales on the piano while showing the note names by letter as well as tone & semi-tone formulas onscreen. The formulas show us whether to move one fret or two frets on a bass before we land on the next note in the scale/mode. For pianists, using only the white keys, the formulas reveal whether to move forward by 1 or 2 keys at a time to get to the next note.
Worth says that if we recall how God Rest Ye Merry Gentlemen sounded different from the major scale, we can have a look at some of the relationships between notes. He shows us the first 5 notes of the C major scale (C-D-E-F-G) and the number of tones & semi-tones that have to be crossed to get from one note to the next. This is also the number of frets that must be crossed from one note to the next on a bass, so if we start on C its 2-2-1-2 to move along to D-E-F-G.
|Note/movement:||C||Move 2 frets ->||D||2 frets ->||E||1 fret ->||F||2 frets ->||G|
He also shows us the first 5 notes of the A minor scale (A-B-C-D-E) and the number of tones & semi-tones we have to move to go from one note to the next in that scale. Starting on A, its 2-1-2-2 to move along to B-C-D-E.
|Note/movement:||A||Move 2 frets ->||B||1 fret ->||C||2 frets ->||D||2 frets ->||E|
After showing each set of 5 notes he plays only the 1 and the 5 from each to illustrate the difference in sound between C major’s 1 & 5 and A minor’s 1 & 5. In both cases, we moved 7 frets to cover 5 notes, but the order in which we moved 1 or 2 frets to get to the next note is different (2-2-1-2 vs. 2-1-2-2).
Each of the notes in a scale is called an interval. The interval in music theory names or defines the type or quality of a note, with regard to its place in a scale. This particular interval is called a 5th, because its the 5th note in the given scale(s). The proper name is actually a “Perfect 5th” because there are other types that differ slightly in sound and physical position, but which are still the 5th note in a scale. Qualifiers such as perfect, major, minor and other terms are important to specifying the type of interval in question. They basically mean move up or down a fret (or a key, for you pianists).
The professors also said to bear in mind that the two notes (root & 5th) from each scale/mode sound nice when played together. So, in C major, playing C & G together sounded good, and in A minor playing A and E together did so as well. This is an important feature about chord tones – they tend to sound good when played together. Its something that our ears have been conditioned to hear – its probably equal parts nature and social conditioning over time.
Worth then plays the interval of a 3rd in our two scales/modes and shows how for A minor, its a distance of 3 semi-tones, and for C major its a distance of 4 semi-tones. In both cases, 3 notes were crossed. For A minor, we move from A to B to C and for C major, we move from C to D to E. Physically, for A minor, we moved 2 frets and then 1 fret, for a total of 3. For C major, we moved 2 frets and then 2 more frets, for a total of 4. They’re still 3rds, but because of what the starting note was and what the ending note was, the physical distance is different.
Once we have an idea of how intervals work (both physically on the fretboard/keyboard and theoretically with regard to their sequence in the scale) the professors go on to show us how the C major scale sounds on the piano and then how the notes of the C major chord (or triad) are found.
When a chord is simply called a chord, it implies that its composed of the root, 3rd note in the scale, and 5th note in the scale. This is specifically called a triad, but the shorthand for it is simply “chord”. If a more complex chord that uses more than 3 notes is played, its called by a more specific name, like a 7th chord, which adds the 7th scale note to the mix. Variation of a common chord also have their own specific names – chord implies a major triad, but a minor triad also has 3 notes, with a slight change that makes it sound different and gives it a different name.
Anyway, we isolate the 3 notes, C-E-G from the pool of C-D-E-F-G-A-B-C in the C major scale. Remember that this is the 1-3-5 that we’ve discusses to death above. They also show us how the C major chord looks when written using music notation. The video shows the 3 notes (C-E-G) placed in the same column, instead of each of them in their own spot, horizontally, along the staff.
Worth then tells us that there are other ways to write this. If we play a lot of rock or jazz, we can use lead sheets which don’t write chords out with notation. Instead, they use chord symbols. C major might be written simply as “C” or as “Cmaj” or even “CM”.
They then do the same with the A minor triad, showing us the A minor scale, isolating the chord tones A, C and E and then stacking them vertically atop each other on the musical staff. On a lead sheet, this could be written as “Amin”, “Am” or even “A-” (with a minus sign).
Moir then switches to piano and plays what he terms 1-3-5 in C major, or C-E-G. He says that there are 7 semi-tones between the C and the G, making it a perfect 5th and 4 semi-tones between the C and the E, making it a major 3rd. If your bass is handy, you can confirm this by simply counting the number of frets from C to G (the C and the G count) and from C to E. Just remember that a semi-tone is a fret.
Because there are 3 notes in the chord, its called a triad, which is the simplest type of chord. So, a triad has a perfect 5th + a major 3rd in it. This is called a Major triad.
- Major triads are composed of a Perfect 5th + a Major 3rd
He then shows is the same thing in D. He plays 1-3-5 on D, which is D-F-A. There are 7 semi-tones between D and A, making it a perfect 5th. But, this time we have only 3 semi-tones between the D and the F instead of 4 like when we played 1-3-5 in C. This is called a minor 3rd. This type of triad, a perfect 5th + a minor 3rd is called a Minor triad.
- Minor triads are composed of a Perfect 5th + a minor 3rd
Then, Moir shows a triad in E, which also results in a minor triad. F follows and is a major triad and G is also major.
B gives us something else though. The chord tones (1-3-5) are B-D-F. There are only 6 semi-tones between B and F, instead of 7 like all the rest. Its one semi-tone smaller. This is called a diminished 5th. It sounds different from the other 5ths. Moir says that we’ll explore it more next week. This type of triad is called a Diminished triad.
- Diminished triads are composed of a Diminished 5th + a major 3rd
He says that we should think about the type of 5th and type of 3rd that we’re combining to build these chords. These 5ths and 3rds are what give them their individual sounds. Ultimately, even if you don’t remember the names of these, the important thing is whether the 5th is perfect or diminished and whether the 3rd is major or minor. Try to remember what a perfect 5th sounds like, and what a major and minor 3rd sound like. That’s actually a part of ear training.
When you hear a note and then play another one that’s a 5th away, there’s a particular quality to the sound that identifies it as a 5th. The same thing goes with a major 3rd and minor 3rd. They each have a distinctive sound. This is also why they have particular roles in a scale, and in music. Try it out. Play a note and then play its 5th. Play a different note and its 5th. As you do this, you’ll hear how they sound in relation to each other. That’s the key of basic ear training – you hear a note, hear another one, and can discern how far apart they are.
Do the same thing with major 3rds and then minor 3rds. You’ll begin to hear the relationship in terms of how much higher the tone is compared with the root not that was played. Then, combine them – play roots followed by 3rds and 5ths. You’ll actually begin to identify them in songs that you know. Its an interesting exercise that I did from time-to-time with the Developing Your Musicianship course.
I’ve heard it said that some notes have a weaker or stronger pull back towards the root note (the 1). If I remember right, chord tones tend to release tension and non-chord tones tend to add tension. Music is supposedly comprised of strings of tension and release, which elicit emotional responses in us on some level. The diminished 5th, now that I’ve listened to it and compared it with a perfect 5th definitely holds a lot of tension.
Worth wraps chords up by showing us what B diminished looks like on the music staff and tells us that it can be written as “Bo” or “B dim” on a lead sheet. He then explains that what they just showed us are all of the triads that can be derived from the C major scale. There are 3 major chords – C maj, F maj and G maj. There are also 3 minor chords – D min, E min and A min (which might be easy to remember as DEA, for Drug Enforcement Agency). B is the only outlier, as its the only diminished chord. He closes by telling us that this gives us 3 types of triads from one set of white notes on a piano.