The 3,400 square metre, 2,800 seat Sala Santa Cecilia (Santa Cecilia Hall) is one of the most innovative concert halls in the world of music. It was conceived for symphonic concerts, and comfortably holds both an orchestra and chorus. The ample 336 square metre stage is set in the centre, and given its modular structure, allows for perfect visibility and optimal acoustics (reverberation time is 2.2 seconds). The dimensions of the hall (1,200 square metre orchestra seating) are at the limit that allows for both natural acoustics and audience attention. As it is in all major concert halls, the audience is seated on 'terraced' risers. The architectonic project as a whole encompasses a volume of about 30,000 cubic metres. The weight-bearing structure of the roof, of exceptional dimensions, is constructed of laminated wooden beams joined by stainless steel components. The lowered acoustical ceiling, truly a conceptual innovation, is made of 26 shells in American cherry wood, each of which has a median surface area of about 180 square metres. The orchestra and balconies are also covered in wood, making the entire Sala a resonating chamber of optimal acoustic performance.