Investigation of Open-air theatre design BEng thesis Thomas Dimasi Supervisor: Dr Bruno Fazenda

Theatre of Epidaurus Evolution of Open-Air Theatres Source: www.wikipedia.co.uk

Measurements of Epidaurus Ancient Acoustics Source: C. van Loenen et al, INFLUENCE OF GEOMETRICAL AND MATERIAL ASSUMPTIONS ON RAY-BASED ACOUSTIC SIMULATIONS OF TWO ANCIENT THEATRES, ICSV23, Athens (Greece), 10-14 July 2016 T20 [s] EDT [s] C80 [dB]

Classic Greek Open-Air Theatre Evolution of Open-Air Theatres Classic Greek Open-Air Theatre Source: K. Chourmouziadou, J. Kang. Acoustic evolution of ancient Greek and Roman theatres. Applied Acoustics 69 (2008) 514–529

Hellenistic Open-Air Theatre Evolution of Open-Air Theatres Hellenistic Open-Air Theatre Source: K. Chourmouziadou, J. Kang. Acoustic evolution of ancient Greek and Roman theatres. Applied Acoustics 69 (2008) 514–529

Roman Open-Air Theatre Evolution of Open-Air Theatres Roman Open-Air Theatre Source: K. Chourmouziadou, J. Kang. Acoustic evolution of ancient Greek and Roman theatres. Applied Acoustics 69 (2008) 514–529

Modelling the Cavea Simple Model Detailed Model Geometrical Acoustic Modelling of Open-Air Theatre Note: validation performed against 1:20 scale model reported in INVESTIGATING THE ACOUSTICS OF ANCIENT THEATRES BY MEANS OF A MODULAR SCALE MODEL, Farnettani et al, ERATO Project Symposium, 20th January 2006, Istanbul (Turkey) Simple Model Detailed Model

Modelling the Cavea More accurate T30 when only the Cavea is present. Geometrical Acoustic Modelling of Open-Air Theatre Note: validation performed against 1:20 scale model reported in INVESTIGATING THE ACOUSTICS OF ANCIENT THEATRES BY MEANS OF A MODULAR SCALE MODEL, Farnettani et al, ERATO Project Symposium, 20th January 2006, Istanbul (Turkey) Simple Model Detailed Model More accurate T30 when only the Cavea is present. Cannot predict T30 if Stage Building is present. More accurate T30 and C50 for model with Stage Building. Overestimates T30 when only the Cavea is present.

Modelling the Cavea Simple Model Detailed Model Geometrical Acoustic Modelling of Open-Air Theatre Source: M. Lisa et al, PREDICTING THE ACOUSTICS OF ANCIENT OPEN-AIR THEATRES: THE IMPORTANCE OF CALCULATION METHODS AND GEOMETRICAL DETAILS, BNAM, 10-14 July 2016, Mariehamn (Åland). Simple Model Detailed Model

Theatre of Syracuse Roman Model Validation against measurements Note: validation performed against 1:20 scale model reported in INVESTIGATING THE ACOUSTICS OF ANCIENT THEATRES BY MEANS OF A MODULAR SCALE MODEL, Farnettani et al, ERATO Project Symposium, 20th January 2006, Istanbul (Turkey)

Theatre of Aspendos Model Validation against measurements Note: validation performed against measurements reported in PREDICTING THE ACOUSTICS OF ANCIENT OPEN-AIR THEATRES: THE IMPORTANCE OF CALCULATION METHODS AND GEOMETRICAL DETAILS, M. Lisa et al, BNAM, 10-14 July 2016, Mariehamn (Åland).

Validation against measurements Conclusions Detail modelling of the Cavea yields best overall predictions. It is the only method for simple geometries. Gives overestimations if only the Cavea is modelled. Has issues with lower octave bands. Requires Scattering based on surfaces dimensions. 1st order diffractions improve predictions. Cavea behaviour cannot be accurately simulated because: some Diffraction effects are omitted. interactions between Cavea and Surfaces are simulated partially. More deterministic algorithms lead to worse predictions.

New Designs Core Cavea Model

Stage Reflectors Model New Designs Stage Reflectors Model

Stage Reflectors Model New Designs Stage Reflectors Model T30 No Audience T30 With Audience Blue model without Reflectors Red model with Reflectors

Stage Reflectors Model New Designs Stage Reflectors Model T30 No Audience T30 With Audience Blue model without Reflectors Red model with Reflectors

New Designs Clouds Model

T30 Three layers of Clouds New Designs Clouds Model T30 Three layers of Clouds T30 Top Clouds layer Blue model without Clouds Red model with Clouds

T30 Three layers of Clouds New Designs Clouds Model T30 Three layers of Clouds T30 Top layer of Clouds Blue model without Clouds Red model with Clouds

New Designs Balcony Model

Balcony Model C50 No Audience C50 With Audience New Designs Blue Core Cavea Model Red Balcony Model

Balcony Model T30 No Audience T30 With Audience New Designs Blue Core Cavea Model Red Balcony Model

Validation against measurements Conclusions Reflective Surfaces Location on T30 frequency balance. Near Stage Area 500Hz Upwards Near Top of the Cavea 250Hz Under Balcony Design. Remove Orchestra Reflections Lower C50 Receivers Near Back Wall Higher C50 with Audience. However Opposite Wall Reflections Lower C50 Focusing Effects are Amplified in GA with Detailed Cavea Modelling.

Further Work GA modelling of Open-Air Theatres Validation against measurements Further Work GA modelling of Open-Air Theatres Cavea/Backwall interactions: Assess the limitations of GA Improve simulation of Cavea behaviour in GA. Address focusing Effects. Other Designs and Features Cavea Slope Vineyard Design … Modern times: Integrated Acoustics and Electroacoustic Open-Air Theatre Design

Questions? Theatre of Aspendos Source: www.turkeytourstravel.com