The Sheldonian Theatre, Oxford stands as one of Sir Christopher Wren‘s architectural masterpieces.

Gilbert Sheldon, Archbishop of Canterbury and Chancellor of Oxford University, commissioned the building and funded most of its construction. Work took place between 1664 and 1669.

Today the university uses the theatre as its principal ceremonial hall. The majestic space hosts lectures, concerts and a wide range of other events. Public tours are especially popular. Visitors can admire the magnificent ceiling paintings up close from the cupola and enjoy wide views across the city.

Acoustics

The building’s acoustics naturally suit musical performances, but speech clarity during lectures and ceremonies needed improvement.

Our long-time collaborators Hewshott invited us to explore ways to enhance speech intelligibility without compromising the hall’s musical qualities.

We identified several issues. One was a relatively long reverberation time which made amplification difficult. Sound levels could be high near to loudspeakers, but too quiet further back in the Upper Circle.

Historic

Drawing on our experience with many other historic buildings, we proposed installing blind boxes above all of the Upper Circle windows with retractable acoustically absorbent blinds. Staff could deploy these blinds when controlling reverberation is essential and retract them during concerts to preserve the room’s lively character.

We also recommended adding steerable column loudspeakers to deliver clearer speech to all audience members on the lower and upper levels, and when the hall is used in reverse configuration where the audience face the Chancellor’s Seat.

Working on a Grade-I listed building always brings unique challenges. We look forward to seeing the project enhance the theatre’s acoustics, once our partners at Hewshott complete their evaluation of our proposals.

Client: Hewshott

Photo credits: Julez Redding / AJA