fixed-bass accordion

musical instrument

Also known as: Stradella accordion

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Last updated

June 26, 2026

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The fixed-bass accordion is a portable musical instrument that uses a hand-operated bellows to force air through free reeds. It has a treble casing with keys or buttons and a bass casing, typically with buttons. The bass side of a fixed-bass accordion, also known as the Stradella system, usually features rows of buttons that produce three-note chords, such as major and minor triads, along with dominant and diminished sevenths. This contrasts with "free-bass" accordions, which offer more flexibility for melodic bass lines. The exact origin of the accordion is debated, with credit given to inventors like C. Friedrich L. Buschmann or Cyril Demian in the early 19th century.1

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accordion
…the rows in traditional “fixed-bass,” or Stradella, models give three-note chords—major and minor triads and dominant and diminished sevenths—while “free-bass” accordions overcome melodic restrictions by providing extra buttons or a converter switch for bass melodies and counterpoint. Many accordions include up to five registers for the basses, allowing each…
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…the rows in traditional “fixed-bass,” or Stradella, models give three-note chords—major and minor triads and dominant and diminished sevenths—while “free-bass” accordions overcome melodic restrictions by providing extra buttons or a converter switch for bass melodies and counterpoint. Many accordions include up to five registers for the basses, allowing each…
Read More