Acoustical transformer for horn-type loudspeaker
US4050541A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 21, 1976 |
| Grant date | Sep 27, 1977 |
| Priority date | — |
| Expiry date | Apr 21, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10K11/28
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An acoustical transformer or "phasing plug" for coupling sound from a speaker diaphragm to the throat of a horn. The phasing plug of the invention is in the general shape of a dome on one side and a truncated cone on the other, and has evenly spaced radial slots or channels formed therein, these slots forming air passageways for propagation of the soundwaves. The walls of the slots are tapered exponentially from their inlet ends at the speaker diaphragm towards a flat plane outlet at the throat of the horn, to provide an optimum impedance match between the output of the diaphragm and the input of the horn; the sound channels formed by the slots exponentially increasing in area between their inlets and outlets. Transformation from a spherical wave front at the input to a plane wave front at the outlet is assured by the shaping of the channels to make the distances between corresponding points at the channel inlets and outlets equal to each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.