David l. Ryan/Globe Staff

Master acoustician Yasuhisa Toyota worked with musicians in November 2011 to test the acoustics of the Gardner Museum's new Calderwood Performance Hall.

David l. Ryan/Globe Staff

Staging filled the concert hall during construction.

David l. Ryan/Globe Staff

Construction work on the skylight of the concert hall in April 2011.

David l. Ryan/Globe Staff

There are three levels of balconies, each featuring only a single row of seats.

David l. Ryan/Globe Staff

Musicians practice in the new concert hall, where there is no stage. Musicians play with seats surrounding them on all sides.

David l. Ryan/Globe Staff

A balcony in the new concert hall.

David L. Ryan/Globe Staff

The undersides of the balconies have an egg-crate design to aid acoustics.

David l. Ryan/Globe Staff

To improve acoustics, the oak-paneled walls have been laser cut with small notches.

T.E. Marr and Son

Isabella Stewart Gardner originally constructed her museum with a two-story Music Room, seen here around 1903. In 1914, the Music Room was demolished to create space for additional galleries, including the Tapestry Room, where concerts continued.

T.E. Marr and Son

The Tapestry Room in 1926.

The Boston Globe - The Boston Gl

The Borromeo String Quartet played in the Tapestry Room at the Isabella Stewart Gardner Museum in 2007.

The Boston Globe

The Tapestry Room has been restored to something close to its original state.