Method and system for providing digitally focused sound

• US 20020131608A1
• Filed: 03/01/2001
• Published: 09/19/2002
• Est. Priority Date: 03/01/2001
• Status: Abandoned Application

• Current Assignee: Lynn Mader
• Original Assignee: Lynn Mader
• Inventors: Mader, Lynn, Lobb, William
• Application Number:
  US09/797,532
• Publication Number:
  US 20020131608A1
• Time in Patent Office: Days
• US Class Current: 381/111
• CPC Class Codes: H04R 1/403 loud-speakers
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers
• CPC Class Codes: H04R 2205/022 Plurality of transducers corresponding to a plurality of sound channels in each earpiece of headphones or in a single enclosure
• CPC Class Codes: H04R 2430/20 Processing of the output signals of the acoustic transducers of an array for obtaining a desired directivity characteristic H04R2203/12 takes precedence
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407

Abstract

A sound system comprising a planar array of at least two sound producing elements and a digital control for controlling the focus of the array. Each element in the array is fed the same signal, but delayed in time according to each element'"'"'s position in the array. Proper selection of time delays result in the audible signal from each element in the array arriving at a given target area coincidentally and coherently, whereas at any other location the signal does not arrive coincidentally, so that, at all but the target area, the sound signals are incoherent and do not add up to the volume that is achieved in the target area. The arrangement of sound elements in a flat planar array allows for the speaker system to be more easily concealed in a floor, wall or ceiling, as well as suspended from above.

Claims

1. A sound system with digitally controlled directivity comprising:

an array comprising at least two sound producing elements;

a digital control circuit responsive to a serial digital bit stream that controls the directivity of the array so that the sound produced by each said element arrives coincidentally at a predetermined target area.

2. The system of claim 1 further comprising a delta modulation converter to produce the serial digital bit stream wherein the digital control circuit is responsive to the serial digital bit stream.

3. The system of claim 2, wherein the digital control circuit comprises at least one digital time delay component and at least one digital driver component.

4. The system of claim 3, wherein each sound producing element is digitally controlled by its own delay and driver component.

5. The system of claim 3, wherein a plurality of sound producing elements are digitally controlled by the same delay and driver component.

6. The system of claim 3, wherein the digital time delay component is implemented by shift registers.

7. The system of claim 3, wherein the sound system further comprises a voltage regulator and power supply wherein said voltage regulator is utilized as a volume control by increasing or decreasing the voltage supplied by the power supply.

8. The system of claim 1 wherein the sound producing elements are arranged in a symmetrical configuration.

9. The system of claim 1 wherein the sound producing elements are arranged in an asymmetrical configuration.

10. The system of claim 1 wherein the sound producing elements are driven cone type loudspeaker.

11. The system of claim 1 wherein the sound producing elements are vibrationally driven panels.

13. The driver of claim 12, wherein a delta modulation converter converts an audio signal into the serial digital bit stream.

14. The driver of claim 12, wherein a pulse width modulation converter converts an audio signal into the serial digital bit stream.

15. The driver of claim 12, wherein the sound producing element moves inward in response to digital bit stream of zeros and outward to digital bit stream of non-zeros.

16. The driver of claim 12, wherein each said digital driver comprises:

an inverting and a non-inverting driver; and

a plurality of MOSFET switches.

17. The driver of claim 12 where the driver is in communication with a voltage regulator, and a power supply and the voltage regulator is utilized as a volume control by increasing or decreasing the voltage supplied by the power supply.

18. The driver of claim 12 wherein the converted bit stream is digitally delayed prior to driving the sound producing element.

19. The driver of claim 12 wherein the sound producing element is a driven cone type loudspeaker.

20. The driver of claim 12 wherein the sound producing element is a vibrationally driven panel.

12. A digital driver comprising:

a driver circuit responsive to a serial digital bit stream to digitally drive a sound producing element.