Diatonic accordions, more commonly referred to as melodeons, are squeeze button accordions with a diatonic scale and an adjustable bass button row that produces basic chords.
There are smaller versions with one or two rows, larger versions featuring rows tuned a semitone apart (i.e. BCC# for chromaticism), and even bigger ones with stradella basses – however these tend to be quite heavy and bulky.
One Row
Single-action diatonic accordions come in many varieties, such as the Garmon (Russian dba), Steirische Harmonika, Slovenian-style accordions and Basque trikitixa accordions. Each button on the right-hand row produces two notes when pushed (closed) or pulled open (opened), with additional short rows or half-rows added as needed to provide accidentals depending on key and relative minor.
An additional row, either a perfect fifth above or four frets below the first row, adds bass buttons for an expanded chordal palette. These instruments may be called organetto (although this term should probably refer to chromatic accordions instead) and may only consist of several keys at most. Yet they remain highly versatile while being relatively light and quiet.
Two Row
Folk musicians commonly utilize two row diatonic accordions as an instrument, although their usage extends into various genres of music. Featuring either one, three, or eight treble rows with 8 bass buttons for control and melodies that cover an extensive spectrum.
This instrument is bisonoric, meaning each button produces different tones depending on whether or not you push or pull on the bellows, giving a distinctive sound which is appreciated in traditional dance music.
A two-row melodeon is the classic example of this type of accordion. While commonly referred to as a chord accordion, such a name can be misleading as diatonic instruments only include notes within their specific scale (with no sharps or flats) while chromatic ones contain all notes simultaneously – so the term melodeon seems more fitting for such an accordion than chord.
Three Row
Long considered the instrument of poor people, accordion has recently come to be taken more seriously by cultural elites thanks to artists like Peter Pot and Irish concertina players who demonstrate its beauty.
Three row diatonic accordions feature a melody row supplemented by two to four buttons for reversals and chord changes, enabling players to play both melodies and chords at the same time. These types of accordions can be found in Alpine and Tex-Mex styles among others; they are known by several names including Schwyzerorgeli or in France as Fisarmonica Diatonica.
Austin Bazaar offers an assortment of Hohner accordions suitable for beginners as well as experienced musicians, all available here. Each instrument comes in various keys for easy playing experience.
Four Row
Melodeon (German style accordion) is a small single action diatonic button accordion with ten buttons that produce two notes depending on whether its bellows are being pushed or pulled, popular among American folk music, Vallenato music, Norteno music and rock genres.
A bandoneon is an integral component of tango music and typically employs a chromatic scale although diatonic scales are also possible. Astor Piazzola was an esteemed bandoneon player and composer known for playing and composing with this instrument.
One row chromatic button accordions, also referred to as organettos, are close cousins of diatonic instruments but feature different keyboard layouts. They’re often employed in variety music when combined with free basses or converter basss. Their closer-together keys enable quick phrasing which often finds itself used classical music composition.
Five Row
There are various diatonic accordions, such as the piano harmonica (also referred to as the Suzuki accordion), used extensively in Irish traditional music and concertinas which are common features in Celtic music. Furthermore, there are numerous chromatic accordions found throughout various genres including Cajun, Zydeco and Tex-Mex music styles.
A chromatic accordion features keys or buttons that span all notes in its range, unlike its diatonic melodeon counterpart that only covers one scale. A two row chromatic accordion, for instance, includes twenty treble buttons and 12 bass notes tuned either a fifth apart or one tone apart to produce a wide chromatic range and allow it to play everything from bandoneon repertoire as well as many other musical styles.