The Rady Shell Performance Stage

San Diego, California, USA

We collaborated with Flanagan Lawrence and ES Global to design a customised version of the Soundform open-air performance shell, scaled up to a span of 38m, to provide a permanent venue in Jacobs Park in California. The stage forms the centre-piece of the San Diego Symphony Orchestra’s new bayside home.

The Rady Shell represents the next iteration of the Soundform concept, which was first proposed by architect Flanagan Lawrence as the ideal shape for outdoor, unamplified music performances, and for which Expedition provided the structural engineering expertise.  

In Jacobs Park the open-air concert hall will be the setting for amplified performances by the San Diego Symphony Orchestra and other world-class international artists. The stage has space for up to 145 musicians at any one time, allowing it to host the full orchestra, a chorus and soloists while delivering an outstanding experience for an audience of up to 10,000. 

As well the acoustic performance of this state-of-the-art venue, its visual appearance was considered to be of paramount importance due to the high-profile location and permanent nature of the structure. 

We worked closely with the architect to design a structural system capable of delivering the exacting lines of the shape they required and tested different bracing members and structural arrangements, honing the design efficiently through the rapid exchange of digital models. 

The final design employs five primary steel arches arranged in parallel with the front of the stage, connected by cross-bracing and with additional ‘lips’ on the front and back to form the overhangs. A PTFE cover encapsulates the structural frame, emphasising its curvaceous shape which widens from the back to the front of the stage and creates the delightful, shell-like appearance. 

The stage has an area of c. 400m2, making it significantly larger than the biggest of the standard Soundform product range, which accommodates up to 124 musicians on a stage of 210m2. Reflective and absorptive acoustic panels designed by US-based firm Salter were installed on the inner and outer shell, and Australian company Fabritecture developed and oversaw the technical design, fabrication and installation of the tensile structure and ancillary buildings. 

Image gallery


It’s an amazing, spectacular outdoor venue. The Shell has a mind-blowing organic quality. You can hear all the different sound balances and perform the way you would in a concert hall, not an outdoor venue.

Rafael Payare

Music Director and Conductor, San Diego Symphony Orchestra

Key People