Architects, engineers and musicians have spatially and acoustically reconstructed Johann Sebastian Bach´s Palace Church, the so-called "Himmelsburg" or "Heaven´s Castle", at Weimar’s Residenzschloss (Palace) in a joint interdisciplinary research project between The LISZT School of Music Weimar and the Bauhaus-University Weimar. A virtual 3D model of the palace church can now be accessed on the Internet: www.florianscharfe.de/schlosskapelle
During a fire in 1774, the musician´s gallery and sanctuary were completely destroyed, along with the organ that Bach had played from 1708 to 1717. Today, the site´s outer surrounding walls, its historic building plans and the famous oil painting by Christian Richter from ca. 1660 are all that survive. Bach´s music, having been played in a bright loft high above the sanctuary, was known to have echoed down through a large aperture or 'sound hole' to the relatively dark, marble-walled chapel below, which is why worshippers felt the experience to have been especially heavenly.
The historic building plans have allowed architect Florian Scharfe to successfully generate a digital model of the entire church where cyber-visitors can move around, even going up to the organ gallery, Bach´s former workplace. The gallery´s reconstruction reveals how, with each Sunday´s cantata performance, choristers and orchestral musicians were required to arrange themselves in a circle formation around the 'sound hole': with a walkway of only ca. 1.5 metres, this 'celestial ring' worked under very cramped conditions.
The musician´s gallery didn´t lend itself to a particularly sacred atmosphere due to poor acoustics lacking reverberation, as engineer Jörg Arnold´s computer-assisted calculations have shown. However, the acoustics were good for playing exact, tight music just what Bach´s polyphonic writing demanded. Below, in the open area above the pews and at Duke Wilhelm Ernst´s middle-level balcony at the rear, the sound would have distinguished itself as having a well balanced resonance typical for a church but also, astonishingly, would have made the finest details of the musicians tight playing audible. In contrast, the sound quality diminished strongly toward the side galleries.
Because Bach created a large part of his most important organ works and cantatas for this architecturally unique space, it is of special interest to musicians to know more about Bach's performance conditions in order to inform their own interpretations. Bach composed all of the cantatas from his Weimar period exclusively for this palace church, among them his first cantata there "Himmelskönig, sei willkommen" BWV 182, in which strong theological relations to the architecture of the unusually tall sanctuary are displayed. Incidentally, during the winter months, it was so mundanely cold in the transcendental dome high above that Bach had to warm his fingers over a basin of hot charcoal.
As a next step, according to The LISZT School of Music harpsichord student Alexander Grychtolik, who conceived the Himmelsburg Project, selected works from Bach’s Weimar period should be able to be digitally realised with the help of the so-called "auralisation" of the Himmelsburg’s specific acoustics by Jörg Arnold, allowing listeners to attend a historically reconstructed concert in the virtual church. The results of the research project can be found in the book "Bachstadt Weimar" from the Wartburg-Verlag, Weimar, scheduled to appear by the end of 2005.