Some musical terms: forms and structures

In the Western world, theatre owes the biggest debt to Greek drama. The stories of gods and heroes, the philosophy and moral dilemmas, the vulgar comedies, the epic dramas: the works of Aeschylus and Sophocles are still performed today. Here you had one actor, discussing his ideas with a chorus of people before Aeschylus expanded the dramatic possibilities by including a second actor; then Sophocles added a third. Monologues became conversations: dialogues and arguments. The scope for conflicting emotions was increased; events could now be acted rather than described. There were now three actors and a chorus and inventive playwrights could use them in different combinations. And what has all this to do with opera?

Well, Greek drama was inspirational to Wagner especially, who adopted the idea of a festival of art for the people in a theatre where every seat gave a clear view of the stage. He also built many of his operas along the structures of monologues and conversations. But the very first operas were based on the subjects of Greek and Roman myths and had a similar form to a Greek tragedy.

As Greek drama often involved one person interacting with a chorus before expanding on their thoughts in a monologue or soliloquy, so did many of the earliest operas (although the chorus may not have been especially large). In other words, one character talking to another in conversation, then expanding on their thoughts in aria. An aria being essentially the point at which words in themselves fail, where music is also needed to express the emotions, where plot gives way to feelings. The principles of the aria remained the same over the centuries, although they grew in length and complexity but one principle remained true: an aria should have a good tune. But just as two people could not talk at the same time in a play, similarly the idea of two people singing at the same time took some time to catch on. Most early operas, are largely aria based. The father of opera is generally held to be Claudio Monteverdi (1567-1643). His operas L'Orfeo/ Orpheus (1607), Il ritorno d'Ulisse in patria/ The return of Ulysees (1640) and L'incoronazione di Poppea/ The coronation of Poppea (1642) are still regularly performed. Here is some Monteverdi: note how the orchestra seems to do very little, especially compared to how the orchestra will develop over the centuries.

(Yes, that is a young Jonas Kaufmann in Il ritorno d'Ulisse). And here is the most beautiful duet, Pur ti miro that ends L'incoronazione di Poppea, but which is now thought to be not by Monteverdi at all! Countertenor Philippe Jaroussky and soprano Nuria Rial sing in concert:

Arias may be useful for expanding emotions but they can rarely advance the plot. In this slightly longer excerpt from Ulisse you can see the extract above in context: but where does the duet begin? It is harder to separate the plot from the emotions: there is no clear beginning and no clear "big tune".

This distinction between plot and aria gradually became more formal and developed into recitative (or recit). The recit moved the plot along and the arias allowed the characters to comment. Recitative itself can be divided into unaccompanied (where the singer, usually accompanied by a harpsichord or a piano, can be a little more liberal with the notes and singing) and accompanied (where the singer is accompanied by the orchestra and has to be stricter and keep with the music: the plot/ emotions become deeper if not quite reflective enough for an aria, still serious enough for music). You can hear some unaccompanied recitative in this clip from the opening of The Marriage of Figaro (1786) with Erwin Schrott and Miah Perrson:

The recit starts at 2.40 until 3.38: notice how much freedom it gives the singers to take their time and "act". By contrast, here is Thomas Allen singing the Count's aria in the same opera. The excerpt starts with a brief section of unaccompanied recit, followed by accompanied recit, then the aria proper begins at 1.32

Occasionally, spoken dialogue will be used instead of recits. This was common in German opera and at the Opera Comique theatre in Paris, which saw the premier of Bizet's Carmen (1875). (Note how as the opera progresses, there is less and less spoken dialogue in Carmen and more music as the story becomes more dramatic and emotional.) However, when Carmen was performed at the Opera Garnier in Paris after Bizet's death, where recitative was expected, recits were composed to replace the dialogue. Compare:

which has recit and dialogue, to:

Of course, sometimes it's not enough to have only one singer expressing their feelings and so there are a whole range of possibilities open to the composer. With a duet we have two singers singing at the same time. In opera, this is usually a love duet between a tenor and soprano, or a friendship duet between tenor and baritone. Verdi also commonly has father/daughter baritone/soprano duets. Soprano/ mezzo duets are also not unusual. Let's have Franco Corelli, tenor, and baritone Ettore Bastianini singing Solenne in quest'ora from Verdi's La forza del destino (1862):

From duet for two voice, on to trio with three. One of my favourite things: the trio between the young singer Antonia, the satanic Dr Miracle and the ghost that he conjures of her dead mother from Offenbach's Tales of Hoffmann (1881). Ileana Cotrubas as Antonia, Phyllis Canaan as her mother, and Nicola Ghiuselev sings the doctor.

Let's add another voice. The quartet from Verdi's Don Carlo (1867):

with Ferrucio Furlanetto, bass, as King Philip; Simon Keenlyside, baritone, as Rodrigo; Sonia Ganasssi. mezzo, as Eboli and Marina Poplavskaya, soprano, as Elisabeth.


Dramatic situations with five or six characters are harder to create and find, but they are out there. Here, for five singers, is the quintet from Wagner's Die Meistersinger von Nurnberg (1868): 

Donizetti's Lucia di Lammermoor (1835) contains a sextet for six singers (and chorus): one of opera's most celebrated moments. 

As opera developed, so the differences between aria/duet/trio etc became less definite and more blurred. Where a composer may have been content before to concentrate mainly on the musical numbers (ie arias, duets), now the operas became more through composed. The modern musical developed in a similar way.


One form we haven't really mentioned so far but who were in it from the beginning is the chorus. The chorus can be anybody: they are royals and peasants, strangers, foreigners, local villagers, whatever the story requires. Two choruses then, the first uplifting, the second rousing.


The Prisoners' Chorus from Beethoven's only opera, Fidelio (1805):

and here, the Anvil Chorus from Verdi's Il Trovatore (1853):

And what if we put all this together, soloists and chorus? Then we have an ensemble where everyone (or, to use an Italian word, tutti) is singing at the same time. (It's important to remember that for all these forms, the singers sing together: three characters may sing, but unless they are all singing at the same time, that is not a trio.) Here is the ensemble Ma tu, re from the second act of Verdi's Aida (1871):

So far, in summary:


Aria, Baritone, Bass, Bass-Baritone, Contralto, Countertenor, Duet, Ensemble, Mezzo Soprano, Number, Quartet, Quintet, Recitative, Sextet, Soprano, Tenor, Trio

Can you remember which is which?