Case Study: Acoustic Design of a Restored Theatre in Thessaloniki

Abstract

This paper discusses the acoustics of a restored theatre in Thessaloniki, Greece. The paper presents the acoustic design principles, discusses the employment of these principles and concludes with an assessment of the success of the design. The acoustic design changes included improvement of direct sound, provision of ceiling and walls reflections, positioning of diffusers, optimising reverberation time and minimising background noise levels. Steeper seating rakes were constructed in the stalls, boxes and balconies. Curved ceiling reflectors were positioned in a new wire frame false ceiling. Lateral wall reflectors were introduced, as were curved side walls near the stage to act as diffusers. Diffusers were positioned in the rear walls and in balcony fronts. Reverberation times were predicted, measured and compared with earlier data, based on the change of volume, the number and design of seats and the volume per seat ratio. Finally, noise level measurements were obtained in most of the spaces in the theatre. Assessment of the success of the design is based on measurement results and on the subjective acceptance by theatre goers.