Many composers that start out writing music are able to create a melody, have an idea for a rhythm or a sense of a particular mood they want to create. Once the initial melody has been created, the difficult part begins -- developing the composition. Composers can approach this problem in a few ways. If you're a composer struggling with this, you've probably tried repeating the melody, creating a new idea, attempting to use your knowledge of phrases to create a new phrase, or rewritten the melody with slight changes to continue the composition. None of these approaches really solve the problem of development in a composition. Instead, you need to look at the melody and discern what form works best for your ideas.

Evaluate the Melody

What have you written so far? Is it a powerful, short thematic idea, a lyrical melody that spans a wide registral range, or perhaps a simple motivic figure that you plan to develop later into a more complex melodic idea? The melody you create determines the form you use. 

Aria Forms for Lyrical Melodies

If the melody is song-like in nature, you'll probably want to use a simple Aria form, such as A-B-A to express your idea. The first section presents your melody and expands on it a bit while the second section introduces a new, complementary, but different idea. Then, you return to the original idea at the end. The reason an Aria form works so well for lyrical melodies is that you want the melody to be memorable. When you change in the middle of the piece to a new section, you alert the audience to a new idea which perks up the ears of even the most stubborn listener. When you return again to the original melody, it's like returning home for the listener. This is one reason why the opening section was repeated literally in so many Classical works. The opening key served as the basis for the entire work and the composer wanted to give the performer enough exposure to the opening key to make it feel like they have arrived home after a brief interlude. 

Symphonic Forms for Short Thematic Ideas

The symphonic forms work well for short thematic ideas. Think about the opening to Beethoven's Fifth Symphony. That motive develops into the basic building blocks for the entire work. The theme returns continually and spawns new versions of the idea. Using a short, powerful figure, you can create several different ideas for a multitude of sections. A basic symphonic form may include an introduction, exposition, development, recapitulation, and possibly a coda. The exposition, development, and recapitulation are a part of all Sonata-Allegro form. The introduction and coda are sometimes included, but not a standard part of the composition. Sonata-Allegro form is basically a more complicated version of the Aria form, with three main sections that introduce the home key, the secondary key, and finally the return to the home key.

Rondo Forms for Motivic Figures

Motivic ideas can be developed using a rondo form. The initial idea can be presented in the first A section, and then an idea that counters that idea in the next B section. A return to the A section reestablishes the focal point of the conversation before providing yet another perspective in the C section. Again, a return to the A section allows us to regain our focus. After the return to the A section, you can end the piece, or continue to add additional sections and move on to a D, E, F, or even Z section if you are capable of keeping the listener's attention that long.

Other Forms

Other forms can also be used in a composition. The ritornello, concerto, passacaglia, and others have their own purposes. The point is that you need to evaluate the melody you are working with and decide before attempting to write the entire piece what form works best to present your ideas. You'll find that many forms are simple embellishments on the A-B-A Aria form. The Rondo form essentially introduces an idea, then moves on to a new idea, and then returns to the A idea. With each repetition, you have an A-B-A form. For instance, in the rondo form A-B-A-C-A-D-A, you basically have three Aria forms. The first one consists of the A-B-A idea, the second A-C-A, and the third A-D-A. 

Creating New Forms

Composers have adopted the A-B-A form and created several new forms based on it. The reason for this has largely to do with the way we perceive information. When you write a piece that continually enforces the main idea, you give the listener a goal or a reason to listen to the composition. Each time that A section returns, you feel as if the composition has a purpose and that your listening is not in vain. The listener begins to listen for that idea to come back. When it doesn't, they feel the piece is missing something. This doesn't mean you can't write a more complex piece that doesn't use an A-B-A version of a form.