DIFFUSION IN THE GROSSER MUSIKVEREINSAAL, A SECOND COMMENT
Further to my letter on Diffusion in the Grosser Musikvereinsaal (G.M.V.) and A. H. Marshall's reply, I should state that the G.M.V. is particularly significantly diffusing.
The G.M.V. combines th6 attributes of a near square cross-section (making it in proportion to its width, one of the highest-ceilinged halls) and a high proportion of the upper side walls are clear of absorption and highly diffusing. This combination means that the majority of sound incident on the ceiling (of that sound that can be considered to be simply reflected) will be subsequently incident on a diffusing wall surface before arriving at a listener. In addition the sound field is interrupted by ten large chandeliers which act as diffusing devices for sound generated towards the ceiling and upper wall surfaces and after subsequent reflections.
The ceiling is divided transversely with beams of modelling approximately 0-30 m at approximately 7.00 m intervals and between the beams are smaller complex forms. Cornices to the edges of the transve'rse beams and at the wall/ceiling junction are complex as are the ceiling roses from which the chandeliers are hung. The above," together with the diffusion provided by architectural forms at the sending end of the hall and the lower wall surfaces make the G.M.V. particularly significantly diffusing throughout the audible spectrum. Departnlent of Architecture, E.