Double Siren

Koenig Acoustical · Physics

Accession Number:

Instrument Name: Double Siren


This siren consists of two wide brass cylindrical chambers, one above the other, each covered with a rotating perforated disk and supported in a brass and iron framework set on a wooden base. To the top of the top cylinder and the bottom of the lower cylinder are affixed angled pipes. The two chambers are connected to one another at their centres by a steel rod. On the sides of each cylinder are four brass knobs affixed to rods that may be pulled in and out. Between these two chambers is brass case with two dials on the front, each connected to a gear in the back. A set of interlocked gears on the top of the upper cylinder is attached to a small handle on the top of the framework.

Primary Materials: Brass, iron, wood, glass, steel


The dial on the left is marked with numbers from 0 to 100 in intervals of 10. The dial on the right is marked with numbers from 0 to 25 in intervals of 5. Three of the four knobs on the top cylinder are marked “12″, “15″, and “16″. The four knobs on the bottom cylinder are marked “18″, “8″, “12″, and “10″. On the top of the framework is stamped “RUDOLPH KOENIG A PARIS”. On the bottom of the wooden base is written “NO 2″ in pencil.

Dimensions (cm): Height =46.5, Width = 25, Length= 26


This piece was used primarily in demonstration rather than experiment. It shows the effects of pure tones produced simultaneously by pressurized air, including interference and combination tones.


Very good: the piece is fully functional. Some minor tarnishing on the brass.

Manufacturer: Rudolph Koenig

Date of Manufacture: c. 1878


University of Toronto Physics Department

Additional Information and References:

A description of this siren and similar sirens can be found in David Patalony’s “Altered Sensations: Rudolph Koenig’s Accoustical Workshop in Nineteenth-Century Paris” New York: Springer, 2009, pp.184-186.

Donated to UTSIC: No