Menu Close

Duochord (Sonometer)


Long wooden rectangular box with three holes on each long side of the box. On the top is attached two metal strings which are connected to tuning tension dials. The strings are attached at one end to the tension dials and the other end to a centimetre ruler. On the top the strings at each end are placed upon wooden bridges which have mebedded glass rods. The strings pass over the glass rods.

Associated with the duochord are 13 wooden movable bridges.

Accession Number:

Alternative Name: Sonometer

Primary Materials: Wood, Metal Alloy, Glass


“Apparatus of Quality, Made by Minneapolis, Carl J. Ulrich Minnesota”, “767” Old catalog number “PHY 76”

Dimensions (cm): 18x24x125 cm


To measure sound frequency in acoustical experiments.


Good. Some rust on metal components. Some other wear, especially large scratches on the bottom of the box. At the tension dial end of the box there is a chip in the end of one of the glass rods and a split in the corner of the wooden box.

Associated Instruments:

Manufacturer: Carl J. Ulrich. Minneapolis, Minnesota

Date of Manufacture: cir. Early or mid 20th century


University of Toronto Department of Physics

Additional Information and References:

Historical Notes:

The movable bridges have been gathered and tagged as items