The History of the Accordion:
The accordion is a relative newcomer on the music scene, having been invented in the early 1800s in Europe (drawing from the concept of older Chinese instruments) and only taking shape in its modern form later in that century. Because the accordion was able to make such a loud sound (remember, amplification hadn't come around yet), it became quite popular, especially for dance music.
Accordions in America:
It is believed that most accordions came to America with traveling German merchants, and gained popularity in various communities, including Germanic regions of the northern midwest, French Louisiana, and the Texas/Mexico border area. The legacy of the accordion's arrival is still evident in the genres of folk music that remain in those regions.
Types of Accordions:
There are three main styles of accordion: diatonic, chromatic and keyboard. Diatonic and chromatic accordions have buttons for keys and keyboard accordions have a piano keyboard for keys. In a standard instrument, the keys are on the player's right-hand side of the instrument. The left-hand side has chord or bass notes, used to play rhythm.
Diatonic accordions have either one, two or three rows of buttons, and each row is tuned to a specific key, having only the notes of that scale. Each button plays a different note depending on whether the bellows are being compressed ("pushed") or expanded ("pulled"). Diatonic accordions generally have two or four left-hand buttons, providing bass notes and/or chords tuned to the same key of the melody buttons.
Chromatic accordions have three to five rows of buttons on the melody side of the instrument. Unlike the diatonic accordion, these buttons are tuned to a specific note, regardless of whether the bellows are being pushed or pulled. Chromatic accordions can generally play in any key, having at least one button for every standard note, whether natural, sharp, or flat. The left-hand side of the instrument contains a variety of chords.
Piano accordions are generally the most recognizable to the general public, having been popularized by people like Lawrence Welk and "Weird Al" Yankovic. The right-hand side is simply a piano keyboard, and works just the same. The left-hand has anywhere from eight to 120 chord buttons.
How Accordions Work:
Accordions make noise when the bellows fill with air and this air is forced out of holes which have a small reed over them. Accordion makers tune these reeds by hand, and each note may trigger anywhere from one to four reeds... the more reeds, the more volume.