By: Scott Cook
The main motivation for the current discussion stems from the practice room. However, the present considerations should apply to any playing situation.
Many of us are familiar with the concept of guide tones for jazz guitar. Generally, these are the notes of the chords, or chord tones, that guide the harmony by specifying mode (major or minor) and quality of seventh chord (Maj7th, min7th, Dom7th, etc).
More specifically, the guide tones of a chord are commonly understood as being the 3rd and 7th of a given chord. For instance, in the chord CMaj7, which consists of the notes C—E—G—B, the guide tones are the notes E and B.
- The note E, which is the 3rd of the chord, specifies that the mode of the chord is major since E is a major-3rd above the root (C)
- The note B, which is the 7th of the chord, determines the quality, or type, of seventh chord that it is (in this case, a major-7th, since B is a major-7th above the root).
Despite their prevalence in jazz, it’s important to understand that the guide tones are not necessarily the most important notes in a chord.
As guitar players, it would not be uncommon to find ourselves playing only the guide tones when comping through the changes of a tune. We can often get away with these relatively simple, two-note voicings when another musician (most often the bass player) is taking care of playing the chord roots.
Example 1: Bars 1-9 of Stella by Starlight, guitar playing guide tones
This example plays through the first nine measures of the tune “Stella by Starlight”.
The basic guitar part is notated, with each chord consisting of only two notes: the 3rd and the 7th, or guide tones, of each of the respective chords. (Please note that the changes included are just the standard harmonies based on the respective guide tones—any extensions commonly used in “Stella” have been omitted.)
Example 2: Impro Over Bars 1-9 of Stella, Using Bb Major Scale
Guide tones are often also used when improvising. Example 2 shows a simple improvisation over the chords from the previous example. Throughout the improvisation, guide tones are highlighted using asterisks.
In each measure, at least one guide tone is included in the improvised melody, and sometimes both. Despite the presence of these, however, it is questionable how well the improvisation actually reflects the tune’s chord progression.
The present article, therefore, considers the effectiveness and appropriateness of guide tones when improvising melodies.
Example 3: Bb Major scale
As a representative example, let’s consider “Stella by Starlight” in a little more detail.
Despite its many seemingly-unrelated chords, and its meandering through a variety of tonal areas, Bb major is understood as the tune’s most prevalent, overarching key. This key is supported in various ways throughout the tune, including the arrival on Bb major at the end of the B Section (mm. 23-24) and the Bb major chord that ends the tune.
The key of Bb major is perhaps most clearly supported, however, by the melody. With the exception of only two notes, every note in the tune’s melody is a member of the Bb major scale.
Example 3 shows one way to play this scale.
The prominence of this scale makes it suitable as a primary source for pitch material when improvising over the changes. Although many of the chords in “Stella” include notes that aren’t in the key of Bb major, the simple fact that it’s melody restricts itself to Bb major almost exclusively suggests that new melodies could feasibly be improvised in a similar way.
For instance, with the exception of the E-natural at the end of m. 4, all notes in the improvisation of Example 2 are from the Bb major scale. Thus, Example 2′s melody might be said to accurately reflect the changes.
The question is: how well?
Listen to Example 4a, which plays the melody from Example 2 without accompaniment. With “Stella’s” characteristic chord progression removed, the melody that is restricted to a single Bb major scale seems a little less coherent, despite the use of guide tones throughout.
As evidence of this, Example 4b plays the same melody, but includes a different harmonization. Though not all of the note choices are ideal (particularly in measure 3), this example shows how easily the Bb major improvisation can be reharmonized.
Example 4a: The melody from Example 3, unaccompanied
Example 4b: The melody from Example 3, reharmonized
There are many approaches when it comes to practicing improvisation. One thing that I often stress is the ability to “hear” the changes that are being improvised on, even when practicing without accompaniment. This means that, when you’re practicing, you shouldn’t just practice running scales at various speeds, or individual licks in various keys. Instead, you should imagine that you’re actually playing over changes, and strive to hear those changes in your head.
One way to achieve this is to make sure that your improvisation includes those notes that most strongly reflect the underlying chords. However, it may not always be immediately evident which notes those are. In many cases, the notes that most strongly reflect the underlying chords are the guide tones. But, as shown in the previous examples, this may not always be the case.
Example 5: Simple improvisation over mm. 1-9, “Stella by Starlight”
Example 5 presents another simple improvisation over the first nine measures of “Stella by Starlight.” Unlike Example 2, this improvisation includes some notes that are not part of Bb major. Like the previous example, asterisks represent the guide tones of the underlying chords, demonstrating the fact that these notes are certainly important.
But, in the example, the guide tones are often functioning as mere passing or neighboring events that are secondary to other melodic notes. For instance, the main melody note in the first measure is E-natural—the root of the underlying chord. In measure 3, the main melody note is F, which is the 11th over Cmin. And, in measure 5, despite its relatively high number of notes, the main melody note would be reduced to G, which is the 9th over Fmin.
In measures 3 and 5, these main melody notes work well primarily because they are derived from the original melody used in Stella. But this isn’t the case in measure 1, which uses the root as principal melody note.
Some of the note choices in Example 5 are made because they can be said to accurately reflect the chord changes within the present context (the context being “Stella by Starlight”). More specifically, when improvising on “Stella,” the notes that I like to aim for in measures 1-2 are E-natural and C#, respectively.
My reasoning is based on the fact that, within the present context, these two notes—regardless of whether or not the latter note is one of the guide tones of the underlying chord—are not part of Bb major. (Over A7, the other guide tone, G, is a member of Bb major, and so reflects the chord change less clearly). As a result, these notes not only help to distinguish my improvised melody from the composed melody of the tune, but they also help to emphasize the distinct sound of the chords in my ears.
The same can be said in measure 8, over Ab7. The 3rd of the chord, C, despite being a guide tone, is a member of Bb major. Another characteristic note often played here is D-natural , which is the #11 over Ab. However, this note is also a member of Bb major..
Based on these, the note that I like to aim for in this measure is Gb, which is the 7th of the chord. Not only is this note a guide tone, but it is also not part of Bb major, and thus helps to emphasize the sound of the change taking place at the moment.
Despite the common understanding of what guide tones are, and their importance in jazz and other styles, the context of a tune can suggest other notes that more accurately “guide” the harmonies. Hopefully, considerations such as those discussed above will help you to hear the chord changes from “Stella by Starlight” in your head while you’re improvising, and encourage you to consider similar contextual options when working through other tunes.
About the Author
Scott Cook PhD, is a jazz guitarist and teacher in Vancouver, Canada. He runs the online free guitar lessons site Scott Cook Music and can be contacted directly through his site.
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