LESSON ONE - (Continued):
As beginners, we tend to think in terms of instruments fitting on top of each other, a little bit like bricks: flutes above, then oboes, then clarinets, then bassoons, for example.
But we can, and should, begin to learn other ways of disposing our instrument. Here are the major ways of placing them:
We are all aware of “stacked”, it is the first reflex of the young (and sometimes not-so-young) orchestrator. In this disposition, the instruments are placed in groups of similar instruments on top of each other. For example two flutes above two oboes, above two clarinets.
There is another way of disposing the instruments. This is by “enclosing” two like instruments between two instruments of another family. For example, two clarinets inside a wider interval made up of two flutes.
By “enbricking” pairs of instruments, we are blending the timbres more consistantly. The sound of a pair of oboes will be more prominent if they are side-by side, yet place them such that a clarinet is between them and you have just created a bit of mystery in the timbral combination.
A last way of combining instruments is to “overlap” them. This is particularly useful when dealing with a very large ensemble. Great care must be taken, however, to overlap timbres on notes that will emphasize our musical intention. Remember that when two instruments are in unison, they will not be louder, but their timbre will be new and unique. This CAN bring out a note in a chord that we did not intend.
There are other ways of combining instruments that incorporate elements of all of these dispositions.
For example, one might double the top note of a chord with two different instruments, but “enbrick” or “enclose” the remaining instruments of those pairs:
This has the advantage of creating a unique timbral quality for the “melodic” top note of the chord.
An additional thing to notice is that the flutes by playing in octaves end up reinforcing their upper partials (that is, the natural harmonics that are part of the flute sound).
Which brings us to something I don't want to go into in detail: overtones and harmonics. Every instrument has a particular vibration. Using an oscilloscope you would be able to see the particular pattern of vibration each instrument makes. And each instrument has a unique pattern. The reaction of the sound to doubling and intervallic superimposition depends in large part on the instrument's particular vibration pattern.
It is always a consideration when placing instruments which ones are doubling at the unison, which ones are in octaves, which ones are in thirds, etc...
Placing instruments in unison will make the overtones of that particular sound conflict with each other. This conflict is not in itself a bad thing. It is simply a consideration. This can either create a more mellow sound, where some of the characteristic vibrations of the instrument are "cancelled out", or it can create a "buzzier" sound where new and unexpected vibrations are created by the conflicting vibrations.
Placing two instruments in thirds will strengthen the over-all timbral quality of those instruments if they are exposed, by giving a large amount of overtones (again, the harmonics that are part of the natural sound of the instrument). In thirds, each note has it's own set of harmonics. Likewise placement in 5ths or 6ths.
Placing in octaves, as has been mentionned, will reinforce the overtones since both instruments are actually "sharing" more harmonics that way, but without the "cancelling out" effect of a unison.
None of these methods of instrumental disposition are “better” or “superior” to any other. It all depends on context. I don't want you worrying too much about this last section. It's a simple fact of accoustics, and there's not much we can actually DO about it. As composers we end up working around any potential problems, and building up our own vocabulary of sounds and sound combinations. This vocabulary, along with your harmonic palette, is what will identify your music as your own. It's not so much a question of choosing a palette, as it is one of simple personal preference.