June 23, 2006
For a definition of a passing chord, how about: A chord that is clearly out of the key of the surrounding chords and usually harmonically unstable, yet resolves to the following chord. (continued)
Notes: Harmonically unstable generally means containing a tritone, and resolving generally means chromatically approaching a strong tone such as a root, 3rd, or top melody note. The chromatic approach may be upward or downward. Stronger resolution is felt if the tritone either closes to a perfect fourth or opens to a perfect fifth. Often, a passing chord is the result of harmonizing a passing tone using a dim7 or dom7 chord. A passing tone is an out-of-key chromatic tone.
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June 23, 2006
The overtone series is a group of pure tones that can be generated when something vibrates. Things can vibrate in different modes, and each mode has a pure tone associated with it. In general, a musical instrument creates vibrations in more than one mode simultaneously, so each note is really made of several pure tones from the overtone series. (continued)
The lowest pure tone is called the fundamental frequency (ff), and the overtone frequencies are multiples of the fundamental (ff, 2ff, 3ff, 4ff, 5ff, etc.) 2ff is an octave above ff, 3ff is a fifth above 2ff, 4ff is an octave above 2ff. 5ff is a major third above 4ff.
As to how the major scale is derived from the overtone series, it is based on the interval of the fifth. If you stack fifths until you have 7 notes, then transpose them into the same octave, you have a major scale. However, the equal tempered scale in use today is derived somewhat differently based on the twelfth root of 2.
By the way, the pentatonic scale is just 5 stacked 5ths. The Lydian-dominant scale can be derived out of the higher overtones 8ff, 9ff, 10ff, 11ff, 12ff, 13ff, 14ff.
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June 23, 2006
The altered scale and its associated chord are prominent in many musical genres including jazz, soul, and R&B. The altered chord is a great tension chord that is typically used in minor keys. (continued)
The scale is composed or the root, b9, #9, 3, b5, #5, and b7. The chord is a dominant seventh type chord with one or more of the altered 9ths and 5ths from the scale. Typical examples of its notation in a chord chart would be C7alt or C7(#5#9). Note that not all dominant chords with chromatic alterations are from the altered scale. For example, any 7th chord with a regular 13th would not be from the altered scale. Also, chords spelled out as dominant 7th with just a b9 are taken to be from the diminished scale.
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June 23, 2006
The pentatonic scale is an ancient scale that occurred independently in many cultures. It is such an extremely prevalent scale that it is worth a little deeper look into it. Whether you are a beginner or a pro, the pentatonic scale has something to offer. (continued)
First, a few definitions are in order. There are major and minor pentatonic scales, but the C major (C, D, E, G, A) has the same notes as A minor (A, C, D, E, G), so there are just 12 to learn. The major one contains the root, 9, 3, 5, b7 while the minor one has the root, m3, 11, 5, b7. [Note that there are other scales called pentatonic just because they have 5 notes, but to me these are not true pentatonic scales.]
And now for some hopefully interesting perspectives! The pentatonic scale can be built by taking any 5 adjacent notes from the circle of fifths and arranging them into a scale sequence. If we start with E and take 5 notes from the circle of fifths, we get E, A, D, G, C. These notes can be re-arranged into the C major or A minor pentatonic scale. Thus the scale is based on the interval of the 5th which in turn comes from the overtone series.
In contrast, the major scale is built by taking any 7 adjacent notes from the circle of fifths. But by taking only 5 notes from the circle of fifths, you end up with no half steps or tritones in your scale. This makes for a scale with virtually no tension, “avoid notes”, or leading tones. It is a mellow, resolved and open sounding scale.
A typical application of the pentatonic scale is to play the A minor pentatonic scale over an Am7 chord. This is useful for establishing the tonal center from which to build, but quickly gets boring if that’s all we play. When using the pentatonic scale in this way, keep in mind the simplicity of it, then build into some more interesting harmonies (e.g. by adding B and F# to get the dorian mode, or a passing tone like G#).
Another application is playing over a major II-V-I where the major pentatonic based on the V fits nicely over the whole progression. For a more colorful example, try playing F# major pentatonic over C7alt - This tritone substitution trick picks up on ALL the color tones! Who says pentatonics have to be boring?
Lastly, it is worth noting that the blues scale is just a pentatonic scale with a passing tone added. Just add an Eb to C major or A minor pentatonic scale to get the respective blues scales.
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June 23, 2006
Major scales and pentatonic scales can be expressed entirely as perfect fourths. For example B, E, A, D, G, C, F is the C major scale as perfect fourths. (continued)
For an interesting effect, try playing that sequence of notes over a Dm7 chord. If your instrument has the range, you can play the sequence completely as stacked fourths. For a different effect, you can play up thee notes, then drop down an octave for the next 3 notes and so on. Let us know about your favorite use of fourths.
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June 23, 2006
The diminished scale is an important scale used frequently in jazz. It is very harmonically colorful since it has 4 half-steps and 4 tritone intervals. We’ll cover the whole-half and half-whole step types and their associated chords. (continued)
Diminished scales are composed of alternating half and whole steps (or whole and half steps). This structure leads to there being only three unique scales to learn:
Dim Scale 1: C, D, Eb, F, F#, Ab, A, B
Dim Scale 2: C#, Eb, E, F#, G, A, Bb, C
Dim Scale 3: D, E, F, G, Ab, Bb, B, C#
Diminished scales are associated with diminished chords and dominant 7(b9) chords. There is sometimes confusion about whether to play the H-W scale or the W-H scale along with a given chord. The scale that goes with a diminished chord ascends with the WHOLE step first, while the scale that goes with a dominant 7(b9) chord ascends with the HALF step first.
Examples:
The scale for Cdim is C, D, Eb, F, F#, Ab, A, B
The scale for C7(b9) is C, Db, D#, E, F#, G, A, Bb
This assures that you get the major 3rd, dominant 7th, and b9 while playing over the C7(b9) chord (and not while playing over the Cdim chord).
The dim scale has some special properties. It is a symmetrical scale, meaning it is made out of a repeating pattern so there are less than 12 unique ones. Anything that is played in the dim scale can be shifted by a minor 3rd and still be in the scale. We often hear soloists taking advantage of this shifting property.
Also see Improvising Over Dominant 7 (b9) Chords
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June 23, 2006
Dominant 7(b9) chords are a colorful variety of dominant chords that can be used in place of regular dominant 7 chords (e.g in a V-I). They are part of diminished scale harmony and we use the second mode of the diminished scale that starts with the half step in the ascending direction. This 8-note scale contains the root, b9, #9, 3, #11, 5, 13, b7.
The diminished scale is not as hard to use as it might seem. There are only 3 diminished scales, and because they are symetric, anything you play can be shifted by minor 3rds.
Let’s take a look at the scale for C7(b9) as an example. The notes are C, C#, Eb, E, F#, G, A, and Bb. Because of the symetry, we can find 4 major triads (C, Eb, F#, and A) that we can play over the chord. This gives us something familiar and easy to play, and they sound pretty cool exept the C triad which is kind of boring because it lacks color tones. (continued)
The triads other than the one based on the root are called upper structures. Piano players often play these upper structures over the cord in various arpaggios and they work equally well for soloing.
Going a step further, we can play any of these triads with their dominat 7th and/or b9 - you get the idea.
Many colorful licks can also be drawn from the 4 half steps contained in the scale. Inverted, these give us some tasty major 7th intervals that we can play with. Try playing Bb-C#-E-A in an ascending or descending line. This contains an A triad, along with major 7th and tritone intervals. Of course this too can be shifted by minor 3rds for more variations.
Keep in mind also that dominant 7 (b9) chords are tension chords, so you should feel tension while soloing over them and resolve to the next chord. This is pretty cool once you get the hang of it!
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June 23, 2006
This is just your basic CDEFGABC scale, however it is important to know all the modes.
Modes:
I : Ionian (or just major)
II : Dorian
III : Phrygian
IV : Lydian
V : Mixolydian
VI : Aoelian or Natural Minor
VII : Locrian
(continued)
Chords in key of C:
I : CMaj7
II : Dm7
III : Em7
IV : FMaj7
V : G7
VI : Am7
VII : Bm7(b5) a.k.a. half diminished
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June 23, 2006
The II-V-I is a common chord progression that creates tension and relief, which in turn creates a sense of forward harmonic motion. In the key of C major, it goes something like this: Dm7-G7-CMaj7. These are simply the diatonic chords based on the second, fifth, and first degrees of the C major scale.
The Dm7 has medium tension. Moving to the G7, tension is increased due to the unstable sound of the tritone interval formed betweeen the 3rd and 7th of this chord. Lastly, the CMaj7 chord sounds completely resolved.
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