Christopher J Link

US Patent:

20140064539, Mar 6, 2014

Filed:

Aug 31, 2012

Appl. No.:

13/600316

Inventors:

Christopher J. Link - Arlington MA, US
Hal Greenberger - Natick MA, US

International Classification:

G10K 13/00
H04R 1/20
H04R 1/02

US Classification:

381345, 181148

Abstract:

An audio system includes a passive radiator that is attached to one end of a lever arm. The other end of the lever arm is attached to a mass that serves to move out of phase of the passive radiator to cancel mechanical vibrations of the passive radiator, but without significantly affecting audio output. The lever arm is attached to a mechanical ground, which may be the enclosure on which the passive radiator is mounted. A system may use multiple lever arms to reduce rocking of the passive radiator.

US Patent:

20050111673, May 26, 2005

Filed:

Nov 30, 2004

Appl. No.:

10/999419

Inventors:

Michael Rosen - Framingham MA, US
Christopher Link - Arlington MA, US
Richard Little - Franklin MA, US
Andrew Munro - Arlington MA, US
Hal Greenberger - Milford MA, US

International Classification:

H04R001/02

US Classification:

381089000

Abstract:

An apparatus for reducing baffle vibration includes a baffle that is subject to vibration. A first transducer that is seated in the baffle includes a first diaphragm that is acoustically coupled to a listening area in a vehicle and also acoustically coupled to a cavity in the vehicle. A first input signal applied to the first transducer causes the first diaphragm to move in a first direction, thereby generating an acoustic output. A second transducer is mechanically coupled to the first transducer. The second transducer includes a second diaphragm that is acoustically coupled to the first diaphragm and also acoustically coupled to the listening area. A second input signal applied to the second transducer causes the second diaphragm to move in a second direction that is substantially opposite to the first direction to reduce a vibration imparted to the baffle while substantially maintaining the acoustic output.

US Patent:

20210127211, Apr 29, 2021

Filed:

Oct 24, 2019

Appl. No.:

16/663065

Inventors:

- Framingham MA, US
Christopher J. Link - Arlington MA, US

International Classification:

H04R 9/06
H04R 7/12
H04R 9/02
H04R 9/04

Abstract:

An electro-acoustic transducer includes a diaphragm and an electro-magnetic motor that is coupled to the diaphragm. The motor includes a voice coil and a magnetic circuit that defines an air gap within which the voice coil is at least partially disposed. The magnetic circuit includes a first, axially polarized permanent magnet that provides a first magnetic flux path and a second, radially polarized permanent magnet that provides a second magnetic flux path. The first and second magnetic flux paths are arranged to interact with the voice coil to drive motion of the diaphragm.