Sperrventile Demo

The Acusticum organ, quite apart from the microtonal stop slider positioning available for almost every stop, also has a number of "Sperrventile" which can be used to limit the air supply to the various divisions of the organ. There are separate valves for the bass and treble of each division; furthermore, the Sperrventile can be set to any position from "fully open" to "completely shut" and every shade in between.

In this short demo, Hans-Ola Ericsson improvises on the manuals, while Gerald Woehl's assistants alter the amount of available air using the Sperrventile. These valves will be under full control of the organist and their positioning will also be programmable using the custom-built combination system.