Atzarin Bandonion Button Arc Comfort and Playability

The minimum spacing of 15.5mm on the inner row using 12mm buttons on the Atzarin bandonion is really quite radical. It leaves a space of 19mm for the finger to fit between buttons on either side of the button being pressed.

However, in practice, when the base of the palm rests on a flat palm rail, the finger tips hit the buttons at an angle coinciding with the empty space between neighbouring buttons on adjacent rows on either side of the pressed button, which should allow even the widest of fingers to play.

As the rows are curved they displace adjacent buttons off a common axis to coincide more closely with the natural position of the finger tips when the hand is arched and the fingers slightly curved, like when drumming your fingers on the table. This allows adjacent fingers to fit together more snuggly and naturally than when having to align the fingertips to press buttons arranged in straight rows. This makes it possible to play notes on adjacent buttons in the same row comfortably despite the close spacing.

The increasing space between buttons on each row, which increases by about 1mm from one row to the next outer row, and the different fingers that are used on each row also contribute to making this button arrangement playable.

The first row, closest to the palm rail, has the closest spacing at 15.5mm heart to heart. However, the buttons on this row will mostly be pressed by the front edge of the thumb, the tip of the index finger or the tip of the little finger, all thinner than the middle and ring fingers.

The outer row, furthest from the palm rail, has the widest spacing at about 17.5mm heart to heart. The buttons on this row will mostly be pressed by the thicker middle and ring fingers as they fall naturally onto this row.