A stunning acoustic for the House of the Catholic Church in Stuttgart
The new purpose-built House of the Catholic Church in Stuttgart is, as convention demands, a polite fusion of the very sensible needs of the church and the contemporary mores of modern architecture. An unlikely place to find a comprehensive d&b audiotechnik installation you might think, but then the church has been wrestling with the tensions of technology and aesthetics for two millennia and has done so very successfully. One only has to look at Le Corbusier's Notre Dame du Haut in Ronchamp, Alsace, to acknowledge that it is entirely possible to marry the traditionalist needs of the church with a modern architectural masterpiece.
'There are however, some traditionalists who find this concept of an open house employing modern technology very difficult,' said lead architect Anton Ummenhofer. 'The acoustics have been a most significant consideration for ecclesiastical rooms for the last two thousand years; here, across three floors, we are providing many different and unconnected spaces, yet Prelate Herr Bock was very clear, these areas must employ the latest and best technology to continue the tradition of hearing clearly.'
Quite simply, between the lobby and the basement conferencing room there exists an array of public areas; a bookshop, a café, a huge information centre (think large civic library with a 3m circular hub at its heart), a marketplace with a further inner lobby beyond and up above a fully galleried balcony level overlooking the ground floor. Rendered in stone, metal and glass in the modern idiom, Ummenhofer has applied acoustic absorbers to some walls and ceilings. 'The stone walls are deliberately rough cut; there is around a 5cm variance in the surface to help diffuse sound and minimise hard reflections.' Remarkably, reverberance times in the public areas are just 0.8 seconds, with the basement conference room just 0.4 seconds.
All areas have d&baudiotechnik PA systems and all are networked to the information centre. 'The demands are varied,' explained Ralf Zuleeg of d&b's education and application support department, who assisted Laauser & Vohl, d&b's installation partner in Stuttgart, with the system design. 'The bookstore and the café only require background music, so just four E8 loudspeakers cover the space easily and comfortably. For the information centre, marketplace, inner lobby and gallery, these areas are multi-purpose; the inner lobby might run a yoga session, the marketplace an exhibition with active live presentation. Again we have selected E-Series loudspeakers, which are light, powerful and give high levels of speech intelligibility over the defined area. A Yamaha DME24 at the info centre allows for simple "housekeeping" pre-set type controls over what is quite a large distributed network: E12s in the Marketplace; E8s in the Gallery above; E8, E12 and E12-SUBs in the inner lobby. Why so much? Because it is envisaged that even dance events can take place.'
The conference room below is also considered a multi-functional space; the room will host youth parties and maybe even fully fledged discos and band events. 'It's quite a large package for this room,' agreed Zuleeg. 'A left/centre/right system with Q7 loudspeakers at the centre, with small line arrays of Q1 and Q7 loudspeakers to the sides and flown Q subwoofers.' From the very beginning Herr Bock the Prelate at HOTCC started from the point of wanting PA systems in every area, and very robust systems that could be pleasant to hear when loud, yet compromise nothing when called upon to provide a clear coherent speech function. 'People have high expectations these days,' concluded Ummenhofer. 'They want perfect pictures on their TVs, and they want to hear perfect sound. The House wanted them to have all of those things too.'