Acoustic Performance of Historic Courtyard Typologies: In-Situ Characterisation and Simulation of the 14th-Century Corral del Carbón, Granada, Spain

This study evaluates the acoustic performance of the 14th-century Corral del Carbón courtyard in Granada, Spain, an unroofed Nasrid al-funduq used as an unamplified performance space. In-situ impulse responses following ISO 3382-1, B-format ambisonic captures, and background noise assessments were integrated with calibrated geometrical acoustic simulations in EASE/AURA. The open-sky boundary prevents late diffuse field consolidation, producing a linear energy decay (Tmid = 1.07s; EDTmid = 1.04s). Strong early lateral reflections yield high clarity (C80 = 4.37dB), definition (D50 = 59%), and speech intelligibility (STI = 0.627). The massive rammed-earth walls attenuate external urban traffic noise by up to 20 dB, securing an NC-35 rating (27.1dBA). To compensate for CAD geometry simplification, a global scattering coefficient (s = 0.80) was required, achieving precise simulation calibration (Tmid= 1.061s). Predictive scenario modelling demonstrates that installing a temporary overhead roof would trap acoustic energy, raising T30 beyond 2.0s and severely degrading acoustic definition and intelligibility. Preserving the open-sky boundary is therefore essential for safeguarding the venue’s intangible acoustic heritage.