The button accordion is an adaptable instrument used in various musical genres. Its versatility has led to it being split into two main categories – diatonic and chromatic.
Diatonic accordions are unique instruments with single note patterns that produce chords when their bellows expand and contract; you will find this system on most melodeons on their left sides.
Diatonic
This type of accordion features one or more rows of treble buttons on its left side and 8 bass buttons producing distinct notes according to a diatonic scale upon which it has been tuned.
Most Irish accordions are tuned B/C or C#/D to accommodate a full range of chromatic notes, while learning B/C may be easier for newcomers because each button corresponds with keys which are half or whole tone apart from one another.
Learning to read music is not necessary when playing this type of accordion; many of the best musicians rely on listening and learning techniques instead. Dry tuning yields crisp, clear tones while wet tuning offers richer, deeper tones.
Chromatic
Button accordions with chromatic treble rows can produce more notes than diatonic ones using equal numbers of treble buttons, giving left hands greater access to more keys and chords more readily.
As well, diagonal movements can be performed either with semitones or full tones (though most find upward movements more comfortable), unlike with other folk accordions such as melodeons where button sequences need to change with bellows direction.
Chromatic accordions can be tuned either wet or dry for optimal sound and feel; wet tuning offers crisper, cleaner sound while dry tuning gives richer, heavier tones.
Stradella
A chromatic button accordion features two keyboards – melody-side with rows of chromatically arranged buttons, and bass side using various free bass or stradella systems – arranged as melody and bass respectively. While there are models which combine both systems into one bass arrangement, their bass arrangement requires different fingering techniques that don’t offer enough keys for players to change registers without missing notes.
A typical stradella bass row features rows of single basses spanning the circle of fifths, as well as chords (major, minor, Dominant 7th, and diminished). Some models also have an additional row of diminished chords above major 3rd row and root note.
Stradella accordions produce similar notes as standard diatonic accordions, yet are arranged diagonally chromatically instead. This allows melodies and chords to be played at true pitch on both treble and bass registers simultaneously.
Maintenance
Maintaining an accordion can be similar to maintaining a car or piano: regular polishing and attention must be paid to every detail. Store it safely when not being played, and avoid extremes of heat or cold.
An accordion that has been properly maintained should play in tune and without issues, with minimal repair needs. Motivation, mechanical aptitude, hand tools and a worktable may all play a vital role. For optimal maintenance of accordion performance it’s also advisable to seek expert guidance from someone knowledgeable on accordion repair techniques.
One of the primary culprits behind poor button accordion sound quality is valve felt compression. To assess this problem, place a long straightedge down each keyboard cabinet, past all treble keys at both ends, and see where each straightedge rests at either end of each keyboard cabinet. Depending on its severity, re-valving may be required. Otherwise, fresh wax on valve felt might help it sound more like its previous state.