A choir rehearsal room, approx. 1000 m3 for up to 100 vocalists, has been recently refurbished to meet ISO23591:2021. Feedback was received from the 22 of the chorus and musical director as to the acoustic. Based on this feedback an adjustment to the design was proposed introducing additional absorptive treatment based on the results of a computer simulation using CATT-Acoustics. After installation measurements were taken in accordance with ISO3382-1:2009. These measurements were identical to those taken previously. Measurement results were compared for the original configuration, the refurbished and the adjusted refurbished choral room. These included room acoustics parameters: Tf, Bass Ratio, Clarity, Sound Strength and Critical Distance. The chorus are now happy, as is the musical director. The rehearsal room meets NS8174:2014 and ISO 23591:2021 will need some adjustment with a focus shifted to loudness rather than reverberation based acoustic criteria.
Dance et al. (Wed,) studied this question.