Brass

How brass instruments make sound

Brass players buzz their lips against a cup- or funnel-shaped mouthpiece. The buzzing lips start the air inside the tube vibrating, and that makes the note.

The main orchestral brass instruments are the trumpet, the French horn, the trombone and the tuba.

The harmonic series

A plain brass tube cannot play every note. With a fixed length of tube, the player can only get a set of notes called the harmonic series. On a tube built on C, these start C, then the C an octave higher, then G, C, E and G, going upwards.

Before valves were invented, trumpets and horns could only play these natural notes. Composers chose instruments of different lengths to get notes in different keys.

Valves and slides

Valves and slides add extra tube while you play. Each new length gives a new harmonic series, so together they fill in all twelve notes.

On instruments with three valves, the second valve lowers the note by a semitone, the first valve by a tone, and the third valve by a tone and a half (a minor 3rd). The trombone uses a slide instead, with seven positions, each one a semitone lower than the last.

Clefs and transpositions

So when a trumpet in B-flat plays a written C, you hear B-flat. When a horn in F plays a written C, you hear F.

Practice tips

General tips teachers often give:

• Warm up gently with long notes and easy slurs before playing harder music.
• Rest often: tired lips make it harder to play well.
• Practise lip slurs between notes of the harmonic series to build control.
• Empty water from the instrument and keep the mouthpiece clean.