Beats in Cochlear Models
Abstract
Beats in cochlear models were studied from two aspects: (1) Their effect upon cochlear fluid motion which, occurring along elliptic orbits, essentially represent Lissajous figures. The orbits expanded and contracted synchronously with the beat rate. Thereby, a partial rectification (asymmetric expansion) became apparent which, occurring in opposite directions in the two scalae across the partition, constituted the beat. This latter phenomenon was caused by the stiffness gradient of the cochlear partition. (2) Their effect on the traveling wave pattern along the partition was originally described by Bekesy. Stroboscopic examination revealed that the beat frequency modulates the two primaries thus producing two additional side bands. The displacement pattern of the membrane when viewed by high-speed motion picture photography, however, did not give any evidence of these five frequencies. Only the intertone (and the beat) were present. It then became apparent that the model is really a pattern analyzer of complex sound.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1959
- Accession Number
- ADA036167
Entities
People
- Juergen Tonndorf