Orgelbau Th. Kuhn AG, 1999
Hochschule für Musik und Theater, Grosser Saal
Orgelbau Th. Kuhn AG, 1999
The technical and tonal concept of the new organ
The requirements for the construction of concert hall organs are, in some important respects, different from those of church organs. One of these considerations concerns the organ's position. Instead of being located behind the congregation up on a gallery, the concert hall organ stands in full view of the audience on a stage. On such stages space is always limited which is why there is only a small depth available for the organ. In churches there is also generally a longer reverberation time than in concert halls, in which intimate chamber music is also intended to be performed. The pipes must be scaled and voiced taking these considerations into account.
The technical system
In organs of this size the Swell and some of the larger pedal pipes generally stand set back behind the Hauptwerk and Positiv. The small depth available here demands an economical use of space with the arrangement of all divisions on one single plane. Although we dispensed with the idea of a «Werk» principle (parts of the façade being assigned to various divisions) in the manner of the Neo-Baroque, the basic arrangement is roughly visible in the façade: in the middle stands the Hauptwerk, flanked on both sides by the Pedal. Above the Hauptwerk is the Positiv. The two-part Swell is at the top on each side between the Positiv and Pedal and is out of view.
Due to the pedals, the organ bench and the necessary surrounding space for registrants and page-turners, the console takes up quite a lot of space. Therefore we tried to find a flexible solution. The console is raised up and can be reached in two ways. When the stage is horizontal, without orchestra tiers, a mobile organist's platform can be attached. When the orchestra tiers are raised up the bench and pedalboard can be placed directly on top of these. When the organ is not in use, the bench and pedalboard can be taken away.
The organ is fitted throughout with slider windchests. The key action, including couplers, is fully mechanical. Electricity is used only for the wind supply and stop action.
The architectural design
The stoplist was drawn up in collaboration with the organ committee. The new instrument was not to be a purely Baroque organ, but should also serve the German and French Romantic period. This aim is achieved mainly by means of the large two-part Swell. It therefore incorporates not only French-style reeds, but also suitable string stops and harmonic flutes.
In the early days of the Organ Movement it was believed that it was enough to fit the late-Romantic organs of the time with a «Baroque manual», a (Rück-) Positiv. At first it wasn't admitted that the uniformity of an instrument would be destroyed through this. In a difficult process it was eventually observed that in organ building everything is mutually dependent in order for a homogeneous end result to be achieved. One should learn from this experience and, through a certain revival of the Romantic, be careful not to repeat the mistake in another direction. It is not enough to fit an essentially Baroque organ with a «Romantic manual», a Swell, otherwise the homogeneity of the instrument is compromised. It is essential to at least make some adaptations to the other divisions (Hauptwerk, Positiv, Pedal). This is not only applicable to the stoplist, but also of particular importance in the voicing.
The Romantic tonal spectrum requires a broad, satisfying and variable range of 8 ' foundation stops with appropriate voicing, bringing out the fundamental. The Baroque, on the other hand, lives from the glistening brightness of the close-meshed Principal pyramid and its combination with the overtone-rich mutation stops. These two basic principles are not necessarily easy to combine.
Being aware of these considerations, we attempted to strike a balance between polyphonic clarity and Romantic shimmer whilst safeguarding a convincing homogeneity of the instrument as a whole.