Vorarlberg organ builders adapt instruments to hotter, drier summers

Organ-building companies in Vorarlberg are adapting new instruments to withstand greater temperature and humidity fluctuations after this summer’s prolonged heat caused problems for organs across Austria, ORF reports.

Historical instruments were particularly affected, according to Wendelin Eberle, managing director of Rieger, an organ-building company based in Schwarzach. The company maintains about 250 organs in Austria and on almost every continent.

Older organs often used solid wood for all their components. Rieger still uses solid wood, but glues the timber lengthwise and crosswise in sensitive parts to make cracking almost impossible. Eberle said modern, well-built organs could respond effectively to changes in the climate.

Rieger’s main organ in Vienna’s St Stephen’s Cathedral came through the hot summer without problems. Built in 2020, it has 185 stops and 12,616 pipes, making it Austria’s largest organ. A Rieger organ built in Vienna’s Musikverein in 2011 was also unaffected. Annual tuning remains necessary for all instruments.

Other organ builders reported a surge in calls after the first three weeks of August. Christian Kögler, whose organ-building company is based in St Florian in the Linz-Land district, said the dry conditions had been unprecedented in his experience. His company maintains about 300 organs in almost all of Austria’s federal states, as well as in South Korea.

Among the most common problems were leaking tone valves, particularly in cone-chest organs built in the 19th century. Their small cone-shaped valves open and close the air supply, but can warp in dry conditions and produce a feared high-pitched sound known as a “howler”. Organ builders also had to regulate mechanisms controlling the air supply and retune instruments.

Kögler has avoided nails and screws when building new pipe organs for decades. This is especially important in Scandinavian churches, where humidity can fall to 15 percent in winter when buildings are heavily heated and rise to as much as 80 percent at other times. He said organs had to be built so their components could move.

He generally builds new organs using a modular system. The absence of complicated individual parts also makes maintenance easier, he said.

Organs built as cheaply as possible, especially those dating from the 1950s to the 1970s, were among the least able to cope with temperature changes. Kögler jokingly called them “panel organs”, referring to their extensive use of glued particleboard and limited use of solid wood.

Philipp Pelster, organist at Salzburg Cathedral and the archbishop’s adviser on organs, said cost had taken priority during that period and that the instruments had not been manufactured with sufficient precision. He said he had also seen particularly negative effects from those organs during this summer’s heat.

Pelster, who trained as an organ builder, regularly services the cathedral’s seven organs himself in response to climate fluctuations. He checks the key travel every week and climbs inside the organs. The demands are especially high because the cathedral hosts about 300 concerts each year.