An active loudspeaker by Hermann Scherchen

loudspeaker ball nullstrahler hermann scherchen
The rotating loudspeaker ball with 32 loudspeakers developed by Hermann Scherchen (sourceörbar-machen-i).

Due to his intensive occupation with recording and reproduction of music the conductor Hermann Scherchen (1891-1966)  became aware of the enormous increment of people listening to music through loudspeakers. He was concerned about the difference between the complex sound diffusion during a concert by the whole orchestra and the very poor representation of the music through one loudspeaker (at that time sound diffusion was often still mono). Scherchen aimed for a recording to sound as if performed in the (acoustic) space, in which it was reproduced and in which the listener of the recording was present. To achieve this, loudspeakers should diffuse sound in such a way, that they “trigger” the acoustics of the space. The recording is not anymore a reproduction of a musical event, which had happened in another space and another time, but the recording now becomes a musical event in itself, sounding as if the instruments are playing in your living room.

To achieve this effect, Scherchen invented a rotating loudspeaker ball, or, as it was called by him, „Der aktive Lautsprecher“ (the active loudspeaker) or “Nullstrahler” (which could be translated as zero radiator, since it was diffusing sound in all directions). Scherchen looked for an alternative for stereophonic reproduction, which in his opinion could not reproduce the sound perception in a space. The rotating loudspeaker ball was developed to distribute the sound in such a way, that each member of the public would sit inside the „sweet spot“ or actually no sweet spot was existing anymore. This loudspeaker was developed in 1959 and consisted of 32 speakers (215 mm diameter) placed on a 70 cm ball. The weight of the whole construction was 150 kilogram. This ball was placed on a stand and able to rotate in all directions. The music played on this loudspeaker ball was not experimental at all, but for example J.S.Bach’s St. Matthew Passion. (I would love to experiment with these loudspeakers though!)

I only have a very bad picture but apparently listening to this loudspeaker was also done outside (in Gravesano, Switzerland, where Scherchen lived). In the second picture you can see the loudspeaker ball in the middle and the audience sitting around:

Nullstrahler loudspeaker ball hermann scherchen
The “Nullstrahler” in action during a meeting in Gravesano.

A beautiful documentation of an exhibition on Herrmann Scherchen’s electroacoustic research has been made by Luca Frei. Bruno Spoerri wrote a detailed history on Scherahen’s studio in Gravesend (see the article Hermann Scherchen und das Experimentalstudio Gravesano (1954–1966) in the book Musik aus dem nichts).

In this video the loudspeaker ball can be seen in rotation (the music heard in the video seems not to be diffused by the loudspeaker ball though):


The loudspeaker has been renovated at the Studio für Elektroakustische Musik der Akademie der Künste, and will appear in concert during the Kontakte Festival (28.09. – 1.10.2017).

More information on this loudspeaker ball can be found in the archive of the Akademie der Künste Berlin and in several volumes of the Gravesaner Blätter:

“Fünf Jahre Gravesano“ (1954 – 1959) in: Gravesaner Blätter No. XIV Volume IV 1959 p. 2.

Technical aspects at the Fifth Anniversary of Gravesano, F. A. Loescher, Gravesaner Blätter No. XV/XVI Vol. IV 1960, p. 6 – 7

Annea Lockwood’s loudspeaker ball  also diffuses monophonic sound through many loudspeakers. And spherical and hemispherical loudspeakers have also been used by laptop orchestras such as the Plork.