Contribution

The Dual Membrane System of the Persian Tar

Authors

* Presenting author
Day / Time: 20.03.2025, 11:00-11:40
Room: Hall E, Poster Island G
Typ: Poster
Session: Musical Acoustics (Poster Island G)
Information: The posters will be exhibited in Hall E north from Tuesday to Thursday, sorted by thematic context in the poster island indicated in the session title. The poster session at the specified time offers the opportunity to enter into discussion with the authors.
Abstract: The Persian Tar is a plucked string instrument with a system of two membranes instead of a top soundboard: a large one, directly actuated by the bridge, and a small one actuated indirectly by the large one. Two methods were used to study the function of the two membranes: First, we recorded the instrument's sound with an artificial head covering no, the small, the large and both membranes and looked for differences in the inter-aural cross-correlation coefficients (IACC). Results indicate that the dual membrane system causes low absolute IACC, relating to the perceived spaciousness of the sound.Then, we measured the eigenmodes of the membranes using a Laser-Doppler vibrometer to visualize the propagation of impulses hammered on the bridge. It was found that the mode of the small membrane is a simple monopole, whereas the modes of the large membranes are complex. These differences in membrane radiation may also explain the perceived spaciousness.