The trumpet and cornet are the smallest and highest pitched of the brass section instruments. They can play very high notes and use a mouthpiece and a vibrating lip to produce the best sounds. Pitch can be altered by simply changing the positioning of the mouth. They use only three keys to play every note. A trumpet was originally a long, straightened horn used for battle. The tubing was curled, making it more portable, and creating an even richer tone.
The French horn is composed of 12 feet of tubing that is wound into a circular shape. Players place their dominant hands on the tubing near the mouthpiece, and the other hand in the bell of the horn. Another three-keyed instrument, this produces a soft and mellow tone, which is perfect for pieces like The Blue Danube Waltz. The mouthpiece is slender, and is easily manipulated by mouth position to create different pitches.
The trombone is an instrument that relies on positioning rather than keys to change the notes and tones. It is a lengthy nine feet of tubing that is curled, with a mobile slide that is moved in and out of the tubing to create different notes. It has a tenor tone, and its shape and size make it much better for slower pieces that need color and tone than for quick pieces.
The tuba is the largest of all of the brass section instruments and creates a deep, bass tone for the orchestra. A tuba is played upright, usually resting on the chair between the legs on the player. It uses a three-key mechanism to change notes, and the lips vibrating in the mouthpiece are the catalyst for changing pitches. There is also a smaller version of the tuba, known as the baritone, which makes slightly higher pitches and tones.
The sousaphone is used more frequently in marching bands, as it is basically a tuba that wraps completely around the body for support and easy carrying. Because of the coiled tubing, it makes a sound slightly different from the tuba and doesn't have as deep as a tone as the tuba does.