Stradella bass system

The Stradella Bass System (sometimes called^[1] standard bass) is a buttonboard layout equipped on the bass side of many accordions, which uses columns of buttons arranged in a circle of fifths; this places the principal major chords of a key (I, IV and V) in three adjacent columns.

^ "Models and Specifications". Titano Accordion Company. Archived from the original on 2020-05-27. Retrieved 2020-05-27.

[1] "Models and Specifications". Titano Accordion Company. Archived from the original on 2020-05-27. Retrieved 2020-05-27.

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