Accordion

The accordion is a box of reeds with bellows in the middle. As you squeeze the bellows in and pull them out, air flows past thin metal reeds, and the keys or buttons you press decide which reeds sound. One player can carry a melody, a bass line and chords at once, which made the accordion a favorite for dances, cafés, folk music and traveling musicians.

How it makes its sound

Each note comes from a free reed: a thin strip of brass or steel fixed at one end over a slot in a metal plate. Moving air makes the reed swing back and forth through the slot, as in a harmonica. On most accordions valves direct the air so that a note sounds the same whether the bellows are opening or closing. You control the volume with the bellows: more pressure makes a louder note, and changing the pressure during a note shapes it, much as a singer does with breath.

Many accordions have several sets of reeds for each note, and register switches select them: an octave higher, an octave lower, or two reeds tuned slightly apart for the shimmering "musette" sound.

The two hands

• The right hand plays the melody on a piano-style keyboard (piano accordion) or on rows of buttons (chromatic button accordion).
• The left hand works the bellows and plays buttons. On the common Stradella bass system, a full-size instrument has 120 buttons in six rows. Two rows play single bass notes (the fundamental bass, and the counterbass a major third higher); each of the other four rows plays a whole chord with one button: major, minor, dominant seventh and diminished. The columns follow the circle of fifths, so the chords of a key sit close together.

Some accordions use a free-bass system instead, with a single note on every left-hand button for playing independent bass lines. Diatonic button accordions are different again: each button plays one note on the push and another on the pull.

How accordion music is written

Accordion music uses two staves: a treble staff for the right hand and a bass staff for the left. Left-hand parts show bass notes and chords, often with small letters or symbols that tell you which row to use. Conventions vary between publishers, so check the key at the start of your book. Bellows changes may be marked above the staff, and planning them (changing direction at the ends of phrases or in rests) is a big part of accordion technique.

Its role and relatives

The accordion is at home in French musette, Italian, German and Eastern European folk music, polka, tango (where its cousin the bandoneón leads), Cajun and zydeco, Tex-Mex conjunto and a growing classical repertoire. Its relatives, the concertina, harmonium and harmonica, also use free reeds.

Tips for beginners

• Choose a size that fits your body. Smaller accordions with fewer bass buttons are lighter and easier to start on.
• Find the C bass button by touch: it usually has a small dimple or stud on it.
• Practice the bellows on their own with long notes, keeping the sound even through each change of direction.