Anglo concertina

The button layouts are generally the same as the original 20-button German concertinas designed by Carl Friedrich Uhlig in 1834.

Within a few years of that date, the German concertina was a popular import in England, Ireland, and North America, due to its ease of use and relatively low price.

An advantage of the Richter tuning is that pressing three adjacent notes in one row produces a major triad.

These added accidentals and notes that already existed in the diatonic rows, but in opposite bisonoric orientation, to make additional chords possible and certain melodic passages easier.

British firms active in the late 19th and early 20th centuries include those founded by Charles Wheatstone, Charles Jeffries (who built primarily Anglo-style concertinas), Louis Lachenal (who built concertinas in both English and Anglo styles and was the most prolific manufacturer of the period), and John Crabb.