The button accordion is a free-reed aerophone used widely throughout European folk music traditions and beyond, such as merengue from Dominican Republic.
Button accordions typically feature single-action (bisonoric) buttons. Each button produces two sounds when expanding or collapsing bellows.
Chromatic System
This accordion features rows of treble buttons arranged chromatically on the melody side (right hand keyboard), connected to either a Stradella bass system or one of several free bass systems. Bayans accordions are particularly popular among Russia and Eastern European musicians and commonly referred to by those names; their vertical rows contain buttons capable of producing successive chromatic notes.
Diatonic models are bisonoric and the push sequence on each row repeats on every fourth button; by contrast, the unisonoric layout of chromatics allows players to finger any key theoretically; in practice many will find certain keys easier than others due to having more notes and being harder to maintain a continuous tune when playing continuously.
Free Bass System
The free bass system (or melody bass) is a keyboard for the left hand that plays single notes instead of chords, enabling performers to perform bass solos within an octave range and works well for accordions with melodica bass button boards stepped with melodica buttons on one or both hands. There are free-bass accordions with up to eight rows of buttons on their left-hand keyboard that make playing difficult; such bassetti accordions may also exist.
An unusual hybrid chromatic/Stradella system exists which utilizes left-hand buttons so as to simultaneously provide access to a chromatic arrangement of keys, Circle-of-Fifths intervals, chord inversions and chord octaves. It is most often found on convertor accordions as well as some Asian piano accordions such as Azeri garmons. Furthermore, some classical accordion music also employs this style; though less frequently learned than its counterparts it can make learning chromatic pieces easier!
Scales
As part of your regular musical practice, playing scales on an accordion may not take up too much of your time unless you wish to improve finger numbers and change articulations on demand. Still, understanding its diatonic instrument notes layout is vital to playing chords or creating melodies with ease.
On its bass side, a diatonic accordion may utilize any number of free-bass systems; there may also be 3 to 5 rows of treble buttons; while its melody side chromatic layout could feature either Stradella or some variation on B system chromaticism.
Some varieties of diatonic button accordions can also be half-bisonoric, producing two notes when their bellows are pressed or pulled; these instruments include Russian garmon, Steirische Harmonika from Alpine regions of Europe and Basque trikitixa trikitixa trikitixa; however melodeons with one row of treble buttons function similar to harmonicas in their operation.
Buttons
Button accordions come in many different forms and sizes. A popular style is called a diatonic button accordion, featuring a melody-sized keyboard with keys corresponding to notes in its diatonic scale and an accompanying bass side capable of sounding principal chords.
Contrary to most musical instruments that have been mass produced using machined parts and robots, accordions remain handcrafted – a factor which contributes to their high price tag.
Buttons on the left (or bass) side of a button accordion are organized chromatically, meaning each pair of bass buttons produces a specific tone when pressed together – for instance pressing buttons 1 and 2 together produces G chord while pressing them 3 and 4 produces C chord. You must be able to navigate this array of bass buttons in order to produce chords and melodies; those familiar with harmonica will find this navigation familiar.