Measurements of Operating Modes on a Loudspeaker Cabinet

Døssing O, Hoffman C, Matthiessen L, Veiergang OJ. Measurements of Operating Modes on a Loudspeaker Cabinet. In: AES Convention 87. Audio Engineering Society; 1989.pp. 2848:1-20. Available from: https://aes.org/publications/elibrary-page/?id=5846

@inproceedings{Dossing1989_5846,
  author = {Døssing, Ole and Hoffman, Christian and Matthiessen, Lars and Veiergang, Ole Jacob},
  title = {{Measurements of Operating Modes on a Loudspeaker Cabinet}},
  booktitle = {AES Convention 87},
  pages = {2848:1-20},
  url = {https://aes.org/publications/elibrary-page/?id=5846},
  year = {1989},
  month = oct,
  publisher = {Audio Engineering Society}
}

TY  - CPAPER
TI  - Measurements of Operating Modes on a Loudspeaker Cabinet
AU  - Døssing, Ole
AU  - Hoffman, Christian
AU  - Matthiessen, Lars
AU  - Veiergang, Ole Jacob
T2  - AES Convention 87
SP  - 1
EP  - 20
M1  - Paper 2848
PY  - 1989
DA  - 1989/10/06
UR  - https://aes.org/publications/elibrary-page/?id=5846
PB  - Audio Engineering Society
LA  - en
AB  - Modal analysis is a powerful tool which can be used to create a dynamic model of a structure, but for some problems the application of a dynamic model is not feasible. In some applications the operating dynamic-excitation forces cannot be determined, and in others only a few of the modes may be excited in normal operation. For such cases, a complete dynamic model is not needed. This paper presents an alternative technique, the measurement of operating modes (OM). The operating mode shapes represent a set of shapes into which the forced vibrations can be decomposed, one shape for each significant modal frequency. The visualized shapes and understanding of the dynamic behavior of a structure and hence how improvements may be made to the design for optimum performance. The technique was applied in the development of a prototype loudspeaker cabinet. To simulate normal operation, the loudspeaker was driven using weighted random noise with shaped auto-spectrum equivalent to a typical music spectrum. The operating modes are identified from complex transmissibility functions measured between a reference accelerometer and a roving accelerometer on the cabinet. Further qualitative and quantitative applications of measured operating modes are also suggested.
ER  -