2 wave siren disks
Date: circa 1875
Inventory Number: 1997-1-1010
Classification: Siren
Subject:
Maker: Rudolph Koenig (1832 - 1901)
User: Harvard Psychological Laboratory (founded 1891)
Cultural Region:
Place of Origin:
City of Use:
Dimensions:
each disc: 0.3 × 40.2 cm (1/8 × 15 13/16 in.)
Material:
Description:
Two large flat brass discs with holes in their centers. One disc has an edge cut into a sinusoidal wave pattern. The other has a far sharper and more jagged wave pattern and three circles of holes radiating outward from its center. The latter is marked "8:15."
In Collection(s)
Signedsinusoidal wave disc is engraved: RK
the jagged-edged disk is engraved: RK.
the jagged-edged disk is engraved: RK.
FunctionThe wave siren was used to study the different timbres produced by varying the phases of the same harmonics. The toothed edges on each of the wheels corresponded to the combination of two pure tones that produced beats and beat tones. Koenig cut the edges of the disks into the waveform that had been produced by that combination. The edge is in effect a sine curve. The disk would rotate on a Savart wheel with an air jet pointed at it. Holes were added in two concentric circles on the disk. Their sounding was compared with the beats and beat tones produced by the wavy edge of the disk.
Curatorial RemarksThe siren to which these disks belonged has not been located (5/22/00). There are no Harvard identifying numbers on these instruments, which is unusal for CHSI Koenig apparatus.
Primary SourcesRudolph Koenig's 1882 "Quelques Experiences d'Acoustique," pg. 236.
Published ReferencesDavid Pantalony, Altered Sensations: Rudolph Koenig's Acoustical Workshop in Nineteenth-Century Paris (Springer, 2009), 303.