Loudspeaker system with broad image source

• US 4,266,092 A
• Filed: 11/02/1978
• Issued: 05/05/1981
• Est. Priority Date: 04/02/1975
• Status: Expired due to Term

• Current Assignee: Bose Corporation
• Original Assignee: Bose Products BV (Bose Corporation)
• Inventors: Barker, Charles R. III
• Primary Examiner(s): Brigance, Gerald L.
• Application Number:
  US05/957,423
• Time in Patent Office: 915 Days
• Field of Search: 179/1 D, 179/1 E, 179/1 G, 179/1 GA, 179/146 E, 181/143-156
• US Class Current: 381/305
• CPC Class Codes: H04R 1/26 Spatial arrangements of separate transducers responsive to two or more frequency ranges
• CPC Class Codes: H04R 1/345 for loudspeakers

Abstract

A loudspeaker system comprises a woofer in a front panel, a midrange driver facing to the front and a tweeter in a corner panel separated from the midrange driver by the woofer and pointing to the front and side with a crossover network arranged to energize at least the midrange and tweeter in an overlapping frequency range. An adjustable deflector is positioned near the tweeter. Another embodiment of the invention has only a woofer and a tweeter on only one corner panel with the crossover network arranged to energize the two in a common frequency range that is greater than an octave.

Claims

1. A loudspeaker system comprising,

cabinet means for supporting loudspeaker drivers,

first loudspeaker driver means supported by said cabinet for radiating sound energy to the front over a first frequency range and having a first polar response,

second loudspeaker driver means supported by said cabinet for radiating sound energy over a second frequency range mostly higher than said first frequency range to the front and side for reflection first from a reflecting surface and then into the listening area along a path after a single reflection that intersects the first loudspeaker driver means axis at a point in said listening area and having a directional second polar response different from said first polar response,

the angle between the axes of said first and second loudspeaker driver means being an acute angle.

an input terminal pair,

and means for intercoupling said input terminal pair and said first and second loudspeaker driver means for providing spectral components in a common frequency range to said first and second loudspeaker driver means,

said means for inercoupling coacting with said first and second loudspeaker driver means to comprise means for attenuating spectral components radiated by said first driver means above a first frequency at the high end of said common frequency range relative to spectral components applied thereto in said common frequency range and means for attenuating spectral components radiated by said second driver means below a second frequency at the low end of said common frequency range relative to spectral components applied thereto in said common frequency range so that the difference between the gain from said input terminal pair to the output of said first driver means and the gain from said input terminal pair to the output of said second driver means is substantially uniform over said common frequency range,

said means for intercoupling coacting with said first and second loudspeaker driver means to comprise means for dissimilarly radiating from first and second locations defined by said first and second loudspeaker driver means respectively spectral components over said over said common frequency range to provide a spatially diffuse source,

said common frequency range being at least half an octave,

said loudspeaker system being free of other loudspeaker driver means which radiate energy having spectral components above said first frequency range primarily directly into the listening area.

2. A loudspeaker system in accordance with claim 1 wherein said common frequency rage is at least an octave.

3. A loudspeaker system in accordance with claim 1 wherein said means for intercoupling coacts with said first loudspeaker driver means and said second loudspeaker driver means to comprise means for establishing the radiated power response as a function of frequency of said loudspeaker system substantially uniform over the frequency range over which said first loudspeaker driver means and said second loudspeaker driver means radiate.

4. A loudspeaker system in accordance with claim 1 wherein said first loudspeaker driver means is supported in a front panel of said cabinet with its axis substantially perpendicular to said front panel and said second loudspeaker driver means is supported with its axis making an acute angle with the axis of said first loudspeaker driver means,

said second loudspeaker driver means having a directional radiation characteristic directed predominantly within a solid angle centered about its axis.

5. A loudspeaker system in accordance with claim 1 wherein said means for intercoupling includes transition network means coacting therewith for establishing a second break frequency near the low end of said common frequency range and a first break frequency at the high end of said common frequency range.

said second break frequency being between 500 and 1000 Hz,

said first break frequency being between 2 kHz and 3 kHz.

6. A loudspeaker system in accordance with claim 5 and further comprising,

third loudspeaker driver means supported by said cabinet for radiating sound energy,

means for intercoupling said input terminal pair and said second and third loudspeaker driver means for providing spectral components in a second common frequency range to said second and third loudspeaker driver means,

said transition network means coacting therewith for establishing a third break frequency near the high end of said second common frequency range between 6 kHz and 9 kHz.

7. A loudspeaker system in accordance with claim 6 wherein said cabinet includes a front panel between left and right angled panels,

said first loudspeaker driver means being supported on said front panel means,

said second and third loudspeaker driver means being adjacent to respective ones of said angled panels.

8. A loudspeaker system in accordance with claim 5, wherein said first break frequency is substantially 3 kHz and said second break frequency is substantially 1 kHz.

9. A loudspeaker system in accordance with claim 1 wherein said second driver means is characterized by a directional radiation pattern having a maximum direction of radiation oriented along an axis directed both forward and sideward of said cabinet means,

and means for selectively positioning said maximum of radiation between a front end position with said direction of radiation more forward than sideward and a side end position with said direction of radiation more sideward than forward.

10. A stereo loudspeaker system in a room having at least a front wall separating first and second side walls generally perpendicular thereto, comprising,

means defining first and second enclosures each having top, bottom, rear, and front panels,

woofer means on the front panel of each enclosure for radiating low audio frequency signals,

tweeter means supported to the side and left of said woofer means in one of said enclosures and to the side and right of said woofer means in the other of said enclosures for directionally radiating high audio frequency signals,

each of said tweeter means characterized by a directional radiation pattern having a maximum direction of radiation oriented along the tweeter axis directed both forward and sideward of the front panel which axis forms an acute angle with the woofer axis,

said first enclosure being the mirror image of said second enclosure with the woofer means and tweeter means on each enclosure assymetrically arranged on each enclosure about a plane perpendicularly bisecting said front panel,

said first and second enclosures being adjacent to said front wall and nearer to said first and second side walls, respectively, than to each other so that sound from each tweeter is directed toward an adjacent side wall.

11. A steror loudspeaker system comprising,

means defining first and second enclosures each having top, bottom, rear and front panels,

woofer means on the front panel of each enclosure for radiating low audio frequency signals,

tweeter means supported to the side and left of said woofer means in one of said enclosures and to the side and right of said woofer means in the other of said enclosures for directionally radiating high audio frequency signals,

each of said tweeter means characterized by a directional radiation pattern having a maximum direction of radiation oriented along the tweeter axis directed both forward and sideward of the front panel which axis forms an acute angle with the woofer axis,

said first enclosure being the mirror image of said second enclosure and

means for selectively positioning said maximum direction of radiation between a front end position with said direction of radiation more forward than sideward and a side end position with said direction of radiation more sideward than forward.