Melodies are mostly made up of notes of the key scale, or even of pieces of the scale, and so are the harmony voices. So, we will look at how a scale can be harmonized. A harmonized scale consists of the scale itself (lead) plus one or more of its harmonies which are called tenor (the next step up from the lead) and baritone (the next step down from the lead). The bass voice does not follow the melody as tightly as tenor and baritone do.
Occasionally, the lead will be the highest voice in which case the next lower voice is still called baritone, while the voice below it is called low tenor, which is an octave below tenor.
Likewise, if the lead is the lowest voice, the next higher voice is still called tenor, while the voice above it is called high baritone, which is an octave above baritone.
Harmonizing a scale
There are several possibilities of harmonizing a scale, each with a different set of chords being formed by baritone, lead, and tenor.
First, let's look at the standard harmonized scale. Its construction principle is very simple:
With every note of the scale (the lead voice), you find the other voices by skipping every other note of the scale. Sounds familiar? Yes, that, too, is the construction principle for the first group of chords shown on Chord Formulas. Here, again, is this table, with just the first inversion, the notes of the scale in bold numbers, primes and sub-primes and the 4th note of the 7 half-diminished 7th chord omitted:
| 1major chord | 1-3-5 |
| 2minor chord | 2-4-6 |
| 3minor chord | 3-5-7 |
| 4major chord | 4-6-1 |
| 5major chord | 5-7-2 |
| 6minor chord | 6-1-3 |
| 7half-dim7th chord | 7-2-4 |
| 1major chord (octave) | 1-3-5 |
So, if we play or sing these chords from top to bottom, what do we get? The standard harmonized scale! 😃
Modifying the harmonized scale – 1
Now, while the standard harmonized scale sounds fine in itself and is the right choice for harmonizing scale segments which act as transitions from a 1 to a 4 or a 5 chord, and vice versa, its problem lies in the fact that if the played chord does not change, only the first sung chord and its octave match that chord (1major). The rest clashes because we cannot expect the backing instruments to play each and every chord sung. Therefore, we need to maximize the number of instances of the 1major chord and its inversions while singing a 3-part harmony scale. The notes 2, 4, 6, and 7 are obviously not part of the 1major chord. There remain 3 and 5, and we make the following replacements:
3minor chord 3-5-7 ⮞⮞⮞ 1major chord 3-5-1
5major chord 5-7-2 ⮞⮞⮞ 1major chord 5-1-3
...arriving at...
| 1major chord | 1-3-5 |
| 2minor chord | 2-4-6 |
| 1major chord | 3-5-1 |
| 4major chord | 4-6-1 |
| 1major chord | 5-1-3 |
| 6minor chord | 6-1-3 |
| 7half-dim7th chord | 7-2-4 |
| 1major chord (octave) | 1-3-5 |
Mind the chords
It's important to make the distinction between chords of the progression played by the band and passing chords which are just sung and do not match the current chord being played. In the above harmony progression we have 4 matches and 4 clashes – the latter is totally OK as long as they are transitional, that is, brief, thus not requiring the band to play the chord sung.As a general rule, with the 1 chord as the current chord, whenever the lead sings a 1, the baritone will sing a 5, and the tenor a 3. If the lead sings a 3, baritone and tenor will sing 1 and 5, respectively, and if the lead sings a 5, they will sing 3 and 1', respectively.
Modifying the harmonized scale – 2
We're about to make yet another modification: The right-most column which we will call baritone (short for 'high baritone') for the moment provides the melody as (read from top to bottom) 5-6-1-1-3-3-4-5, and we notice a doubling of 1 and 3. Since the first 1 belongs to the substituted 1 major and cannot be changed, let's change the second 1 to 2, and we get:| 1major chord | 1-3-5 | |
| 2minor chord | 2-4-6 | |
| 1major chord | 3-5-1 | |
| 2minor chord | 4-6-2 | The 4major 4-6-1 has turned into its 'relative minor' chord, the 2minor 😲 ! |
| 1major chord | 5-1-3 | |
| 6minor chord | 6-1-3 | |
| 7half-dim7th chord | 7-2-4 | |
| 1major chord (octave) | 1-3-5 |
By the way...
2minor is called the 4major chord's relative minor because both the 4 major and the 2 natural minor scales contain exactly the same notes. The relative minor scale starts always 3 half-tones below the tonic or key of the major scale.
6minor is the relative minor chord to the 1major chord. Below, you can see that the major scale and its relative (natural) minor scale is made up of the same notes:
| 6 natural minor scale | 6-7-1-2-3-4-5-6-7-1 |
| 1 major scale | 6-7-1-2-3-4-5-6-7-1 |
It doesn't stop there....
Modifying the harmonized scale – 3
Please note that in this progression as well as the one before, the lead goes from 1 to 3 (1-2-3) in two steps, with tenor and baritone following that pattern. But that means that the baritone leaves out the 7th note of the scale by going 5-6-1.Then, as the lead goes from 3 to 5 (3-4-5) again in two steps, the same note-skipping happens to the tenor which in turn goes 5-6-1. This note-skipping happens all the time in harmony singing.
By the way, the transitional 6 doesn't have to be a 6 at all times. It could just as well be a 7b or a 7, depending on which one sounds best in the context.
The lead then reaches the high 1 from 5 in three steps (5-6-7-1), while for tenor and baritone there is only one scale note available to bridge 1 and 3, and 3 and 5, respectively. In the case above, the baritone doubles up on 3, and the tenor on 1 to fill the gap.
But there are other possibilities using chromatic notes. Probably the best sounding progression is this:
| 1major chord | 5 - 1 - 3 | |
| 2minor chord | 6 - 2 - 4 | By substituting 2 for 1 in the tenor and 4 for3 in the baritone, the 6minor has turned into an inversion of the 2minor chord! |
| 7major chord | 7-3b-5b | |
| 1major chord (octave) | 1 -3 - 5 |
In its entirety:
| 1major chord | 1 - 3 - 5 |
| 2minor chord | 2 - 4 - 6 |
| 1major chord | 3 - 5 - 1 |
| 2minor chord | 4 - 6 - 2 |
| 1major chord | 5 - 1 - 3 |
| 2minor chord | 6 - 2 - 4 |
| 7major chord | 7-3b-5b |
| 1major chord (octave) | 1 -3 - 5 |
Isn't it striking that 1major now alternates with 2minor? In its simplicity, this scale is the mainstay of harmony singing which you will use all the time — probably not the whole scale, but parts of it.