The concertinaed section in the center of an accordion is known as the accordion bellows. The bellows are inflated and deflated to allow air to pass through various metal reeds inside the instrument that generate noise. Unless the bellows are contracted or expanded, an accordion will not produce any sound. The effect of the bellows on the tone produced the instrument is the main concern of an accordionist.
The cheng, a Chinese instrument, was the first to use vibrating reeds to produce sound, but the accordion as we know it today originated in Germany. The diatonic accordion and the piano accordion are the two types of accordions. The most common type is the piano accordion, which has a piano keyboard on one side and several small bass buttons on the other. The diatonic accordion has circular melody buttons in rows of ten and very few bass buttons, and can only produce notes in a limited number of keys. A piano accordion does not produce a different note depending on which way the bellows are pulled on a diatonic accordion.
The bellows are always required to produce sound, regardless of the type of accordion. Accordion bellows are located between the bass and melody buttons on the instrument. Accordions frequently have special “air” buttons that allow air to pass through the bellows without the instrument producing a note. Some accordion music has specific notation for whether the bellows should be expanded or contracted during a particular measure. Stability and tone are the two main goals for controlling the accordion bellows.
The melody side of the accordion is usually sat on the knee beneath the stronger hand of most accordion players. The weaker hand usually operates the accordion bellows, leaving the melody section and that half of the instrument stationary on the player’s knee. This aids in the instrument’s stability, allowing for greater control over the tone produced and finger dexterity.
Supporting the bellows is only necessary because the accordion’s bellows have a significant impact on the instrument’s sound. When you push or pull the bellows hard, you’ll get a louder, harsher tone than if you do it softly. Experienced players develop a sense of how to manipulate the bellows depending on the piece’s intended mood. Every bar, every two bars, or every four bars, the direction in which the bellows are moved changes.