When we think of a cohesive family, we think of a group that all has similar characteristics. They must all share common traits. The woodwind family may be the most dysfunctional “family” in all of music. The only thing that the different instruments have in common is that they are pipes with holes pierced throughout their length through which a vibrating column of air produces the sound. Past this, the similarities end.
Let’s look first at the most cohesive group in the orchestra, the strings. There are four standard instruments that make up the string family: the Violin, the Viola, the Cello, and the Bass. All of these instruments operate on a very similar principle: a length of string is set into motion by a bow or by being plucked. The quibble over the Bass being a member of a slightly different family (the Viol family) is so minor that it is hardly worth a mention.
Is the woodwind family like the string family?
In fact, that’s a big no.
If we look at the standard orchestral winds, we see four sections: flutes, oboes, clarinets, bassoons. All four of these sections can be seen as a family in their own regard.
The flutes are the clear outlier. Their sound is the only one not produced by a vibrating reed. The flute is usually the soprano extraordinaire, and it is this role that it is most often used in as a member of the woodwind “family.”
Oboes and bassoons can easily be grouped together. While they are mechanically different and constructed very differently from each other, they are both fundamentally conical bore, double reed instruments. Their ranges neatly mesh together to form a solid section from soprano to bass. With this grouping, the double reeds are the largest family of woodwinds in most orchestras.
Clarinets form a family all to their own. It is the largest family from the point of view of number of species. It is also the only family to have a uniform timbre from the deepest contrabass to the highest treble.
Where does this leave us?
It leaves us with three woodwind families and not one. It leaves us with our most disjunct section of the orchestra.
This means that mixing of instruments within the woodwind section is one of the trickiest skills for an orchestrator to learn. It means that in an orchestra all the woodwinds are treated like soloists, whereas in a band, this cannot be the case. In a band, the woodwinds must be thought of as separate choirs. This is due to the lack of a cohesive sting section. It is also why the auxiliary members of the woodwind family are far more imperative in a band than they are in an orchestra.
I have left out two instruments, the recorder and the saxophone. These two form their own complete family separate from the others. Recorders are closest to the flute, while saxophones are an add-mixture of clarinets and double reeds.
By thinking of the woodwinds as 3-5 separate families and not as a cohesive unit, this will help with acoustical problems of blending, spacing, and intonation.