Matthew G Polk

US Patent:

20050058315, Mar 17, 2005

Filed:

Sep 12, 2003

Appl. No.:

10/660727

Inventors:

John Poling - Sparks MD, US
Bradley Starobin - Baltimore MD, US
Allen Baron - Baltimore MD, US
Matthew Polk - Baltimore MD, US

International Classification:

H04R001/02
H04R001/20

US Classification:

381337000, 381345000, 381339000

Abstract:

A port for a loudspeaker is disclosed which is sufficiently weather resistant for long term outdoor use and which prevents debris, insects and other vermin from entering the loudspeaker and which is compact and efficient.

US Patent:

44894325, Dec 18, 1984

Filed:

May 28, 1982

Appl. No.:

6/383151

Inventors:

Matthew S. Polk - Baltimore MD

Assignee:

Polk Audio, Inc. - Baltimore MD

International Classification:

H04R 500

US Classification:

381 24

Abstract:

Apparatus for reproducing sound having a realistic ambient field and acoustic image is used in a stereophonic sound reproduction system having a left channel output and a right channel output. A right main speaker and a left main speaker are disposed at right and left main speaker locations, respectively, which are equidistantly spaced from a listening location along a listening axis perpendicular to a line joining the left and right main speakers. A right sub-speaker and a left sub-speaker are respectively disposed at right and left sub-speaker locations equidistantly spaced from the listening location, and further from the listening location than the main speaker. The left and right channel outputs are respectively coupled to the left and right main speakers. A left channel minus right channel difference signal is coupled to the left sub-speaker and a right channel minus left channel difference signal is coupled to the right sub-speaker. In one embodiment, the main and sub-speakers for each channel are respectively incorporated in a common enclosure to fix the spacing therebetween.

US Patent:

41774310, Dec 4, 1979

Filed:

Mar 17, 1978

Appl. No.:

5/887740

Inventors:

Matthew S. Polk - Baltimore MD

International Classification:

H03F 126

US Classification:

330149

Abstract:

A loudspeaker-cable interface for use in audio reproduction systems including a capacitor and resistor for effectively terminating the cable with a predetermined impedance at frequencies above the audio range. The interface operates to inhibit generation of spurious high-frequency oscillations which could cause damage to the amplifier.

US Patent:

55175732, May 14, 1996

Filed:

Aug 23, 1994

Appl. No.:

8/294412

Inventors:

Matthew S. Polk - Baltimore MD
Colin B. Campbell - Baltimore MD

Assignee:

Polk Investment Corporation - Wilmington DE

International Classification:

H04R 2500

US Classification:

381159

Abstract:

A vented loudspeaker system is provided which has at least one active driver and a port opening in a speaker cabinet, Disks or baffle plates are mounted a predetermined distance to and concentric to the port opening, resulting in a vented system achieving an equivalent performance as would result from a flared, ducted port, but with several performance advantages and simpler construction. Flow guides are provided, attached to the disks or baffle plates, extending back into the port to block areas of stagnant air and enhance laminar air flow.

US Patent:

D2519739, May 29, 1979

Filed:

Mar 4, 1977

Appl. No.:

5/774495

Inventors:

George M. Klopfer - Baltimore MD
Matthew S. Polk - Baltimore MD
Sanford Gross - Baltimore MD

International Classification:

D1401

US Classification:

D14 33

US Patent:

58091548, Sep 15, 1998

Filed:

May 26, 1995

Appl. No.:

8/453557

Inventors:

Matthew S. Polk - Baltimore MD

Assignee:

Britannia Investment Corporation - Wilmington DE

International Classification:

H04R 2500

US Classification:

381159

Abstract:

A vent loudspeaker system is provided which has at least one active driver and a port opening in a speaker cabinet. Disks or baffle plates are mounted a predetermined distance to and concentric to the port opening, resulting in a vented system achieving an equivalent performance as would result from a flared, ducted port, but with several performance advantages and simpler construction.

US Patent:

49033000, Feb 20, 1990

Filed:

Apr 21, 1989

Appl. No.:

7/342042

Inventors:

Matthew S. Polk - Baltimore MD

Assignee:

Polk Investment Corporation - Wilmington DE

International Classification:

H04R 502

US Classification:

381 24

Abstract:

A loudspeaker system is provided for installation in a space between a front panel and an enclosed area behind the front panel of a partition such as a wall, ceiling or floor fronting a listening area. Electroacoustical transducers are provided which have a two sided vibratory diaphragm driven by an electrical signal. An enclosure mounts the electroacoustical transducers such that one side of the vibratory diaphragm is in contact with air outside the enclosing between the front and rear panels of the partition, with the enclosure being configured to substantially enclose and define a specific volume of air within the enclosure having a predefined acoustic compliance and which is in contact with the other side of the vibratory diaphragm of the electroacoustical transducers. The enclosure is mounted to the structural partition such that the enclosure extends into the space behind the front panel of the partition so that the one side of the vibratory diaphragm contacts a volume of air outside the enclosure within the space behind the front panel of the partition. A passive radiator such as a port which has a specific acoustic mass is provided for coupling the specific volume of air enclosed by the enclosure to the air outside the enclosure in the listening area.

US Patent:

49249630, May 15, 1990

Filed:

Jan 5, 1989

Appl. No.:

7/294150

Inventors:

Matthew S. Polk - Baltimore MD

Assignee:

Polk Investment Corp. - Wilmington DE

International Classification:

H05K 500

US Classification:

181144

Abstract:

A loudspeaker system is provided for installation in a space between a front panel and an enclosed area behind the front panel of a partition such as a wall, ceiling or floor fronting a listening area. Electroacoustical transducers are provided which have a two sided vibratory diaphragm driven by an electrical signal. An enclosure mounts the electroacoustical transducers such that one side of the vibratory diaphragm is in contact with air outside the enclosure, with the enclosure being configured to substantially enclose and define a specific volume of air within the enclosure having a predefined acoustic compliance and which is in contact with the other side of the vibratory diaphragm of the electroacoustical transducers. The enclosure is mounted to the structural partition such that the enclosure extends into the space behind the front panel of the partition so that the one side of the vibratory diaphragm contacts a volume of air outside the enclosure within the space behind the front panel of the partition. A passive radiator such as a port which has a predetermined acoustic mass is provided for coupling the specific volume of air enclosed by the enclosure to the air outside the enclosure in the listening area.