Orchestral Voicings Part 5: Extended Harmony and Problematic Intervals 2

In the last part I mentioned already that the minor 9th is a problematic interval and should generally be avoided in voicings unless you have a plausible reason for it. Unfortunately, this interval can happen quite quickly in quite a few chord types and particularly when you don't take care about how to voice them.

Probably the most dangerous chord in this regard is the major 7th chord. As soon as you repeat the root note higher than the major 7th, things might become problematic:

https://soundcloud.com/robin-hoffmann/cmaj7/s-oRyfj

This problem is also present in more complex maj7 voicings like a Cmaj9(#11) chord. The third option shows a slightly revoiced version without the problem which just by a few alterations becomes much more stable and "structured":

https://soundcloud.com/robin-hoffmann/cmaj911/s-HqGvX

This chord contains another danger in regards of potential minor ninths which is the #11 (in this case F#).

If you voice the fifth of the chord higher than the #11, you will get a potential minor ninth as well:

https://soundcloud.com/robin-hoffmann/cmaj9bad11/s-mqYAx

There are a few more possible traps such as a higher dominant 7 over a natural 13. However, remember from the last part that the general structure should remain the order of "lower structure" below "higher structure" which usually if followed eliminates such cases.

The real danger with this doesn't lay particularly in chosing a bad voicing in your supporting string or trombone chords but rather in melodic movement such as this example:

https://soundcloud.com/robin-hoffmann/cmaj7melody/s-QrRjc

Notice how the minor 9th falls on a heavy count of the bar and therefore get's emphasized.

As a comparison, here is another example where the minor ninth falls on a weak beat and is a passing tone in the melody where this problem is not existing:

https://soundcloud.com/robin-hoffmann/cmaj7_passing/s-iMYPQ

These cases are however a little bit of a gray area as they are extremely tempo dependant. The general rule of thumb is that with anything slower than a quarter note at tempo 80 our ear tries to make a harmonic sense of that "moment" so if I were to play the example above very slowly that clash would become prominent again and I would need to adjust the underlaying harmony accordingly. If I played the "bad" example from two examples above really quickly, our ear would start to simply ignore the clash:

https://soundcloud.com/robin-hoffmann/cmaj7_passing_tempo/s-ybxuw

Also, the rhythmic placement plays a role here. On heavier beats such a clash will be way more obvious than on weaker beats.

Let me state here that this is a rule of thumb and requires additional judgement by your ear.

In this example I added a side line here which has a strong melodic contour of stepwise descension. On count three of the first bar however we reach that minor ninth without it being troublesome for the ear. The melodic plausibility of these two lines that "clash" for this brief moment weaken the dissonance of it. Instead they seem to create a rather attractive moment of rub that resolves pretty quickly.

https://soundcloud.com/robin-hoffmann/minor9th_working/s-jK46f

 So the academically correct way would be to avoid minor ninths in such contexts. In practical context however, if you use them cleverly and consciously you can easily "sell" them to the audience. The general idea as with every "theoretically forbidden thing" is always: they shouldn't happen accidentally but if you use them consciously you can create very interesting things with them.