H04R 27 - Public address systems

Patents for H04R 27 - Public address systems (2,454)
02/1995
02/14/1995	US5389829 Output limiter for class-D BICMOS hearing aid output amplifier
01/1995
01/26/1995	DE4324611A1 Method for providing sound to an area and arrangement for carrying out the method
01/24/1995	US5384854 Co-processor controlled switching apparatus and method for dispatching console
01/17/1995	US5383079 Portable information reproducing and voice amplifying apparatus
12/1994
12/28/1994	CN2186469Y Multifunction electronic wind instrument
12/08/1994	WO1994028679A1 An integrated video and audio signal distribution system for use on commercial aircraft and other vehicles
12/07/1994	EP0627868A1 Loudspeaker driver surrounding
11/1994
11/29/1994	US5369710 Sound field correcting apparatus and method
11/24/1994	WO1994027397A1 Computer-to-telephone interface
11/08/1994	US5363434 Audio distribution system
10/1994
10/19/1994	EP0620697A1 Audio/video information system
10/06/1994	DE4092322C2 Funnel loudspeaker and associated sound funnel
09/1994
09/29/1994	WO1994022277A1 Sound pick-up and reproduction apparatus and use thereof for conference calls
09/21/1994	CN2178033Y Memory type megaphone
09/20/1994	US5349480 Portable audio apparatus
08/1994
08/31/1994	CN2175996Y Antenna transmit-receive device composed of wirless microphone and pocket receiver
08/16/1994	CA2027138C Loudspeaking telephone station including directional microphone
07/1994
07/26/1994	US5333202 Multidimensional stereophonic sound reproduction system
07/20/1994	EP0606387A1 Process and system for sound pick-up, apparatus for sound pick-up and reproduction.
07/20/1994	CN2172553Y Telephone transmitter with noise silencing function
05/1994
05/11/1994	DE4237180C1 Large loudspeaker with high efficiency - has individual speakers arranged on common plastics foam diaphragm
04/1994
04/12/1994	US5303109 Portable information reproducing and voice amplifying apparatus
04/06/1994	EP0590903A1 Output limiter for class-D BICMOS hearing aid output amplifier
04/06/1994	CN1085037A Radio frequency modulatng transmitter
03/1994
03/02/1994	EP0584299A1 Improved audio distribution system
02/1994
02/23/1994	CN2157647Y Hand loudspeaker capable of recording and playback
02/17/1994	WO1994004010A1 Concert audio system
02/17/1994	CA2139866A1 Concert audio system
02/02/1994	EP0581261A1 Auditory prosthesis with user-controlled feedback
01/1994
01/30/1994	CA2100015A1 Auditory prosthesis with user-controlled feedback cancellation
12/1993
12/29/1993	EP0575598A1 Multi-zone audio distribution amplifier
12/28/1993	US5273437 Audience participation system
12/09/1993	DE4218105A1 Public address system synchronised for undistorted sound reprodn. - employs buffer storage and delayed transmission of pulse signals from microphone to array of loudspeakers at different distances
11/1993
11/30/1993	US5266751 Cluster of loudspeaker cabinets having adjustable splay angle
10/1993
10/19/1993	US5255322 Multi-zone audio distribution amplifier
09/1993
09/30/1993	DE4307008A1 Acoustic field corrector using cascaded delay circuits - operates by addn. of outputs of cascaded combinations of echo-generating delay stages and coefft. multipliers
09/21/1993	US5247581 Class-d bicmos hearing aid output amplifier
09/15/1993	EP0226613B1 Noise supression system
08/1993
08/25/1993	EP0391933B1 Method and device for generating sound in a space for people
08/18/1993	EP0555951A1 Loudspeakers
08/11/1993	CN1075240A Body sense speaker
08/10/1993	CA2046659C Loudspeaker and horn therefor
08/03/1993	US5233663 Simultaneous interpretation system
08/03/1993	US5233661 Sound field variable apparatus
07/1993
07/21/1993	CN2138869Y Multiway microphone mixing and separating device
07/10/1993	WO1993014611A1 Improved audio distribution system
07/10/1993	WO1993014575A1 Multi-zone audio distribution amplifier
07/10/1993	CA2105059A1 Audio distribution system
07/10/1993	CA2104947A1 Multi-zone audio distribution amplifier
07/06/1993	US5225944 Portable audio apparatus
06/1993
06/30/1993	CN2137417Y Multifunctional microphone
06/02/1993	CN2135222Y Frequency-modulation stereo transmitter and radio active voice box
05/1993
05/26/1993	CN2134765Y Protecting means for overload short circuit and reverse of large power megaphone
05/25/1993	US5214543 Portable audio apparatus having a power savings device
05/19/1993	CN2134018Y Miniature pen-shaped deaf-aid
05/04/1993	US5208717 Portable information reproducing and voice amplifying apparatus
04/1993
04/15/1993	WO1993007730A1 Process and system for sound pick-up, apparatus for sound pick-up and reproduction
03/1993
03/31/1993	EP0534804A1 Class-D BICMOS hearing aid output amplifier
03/17/1993	EP0520067A4 Improved audio distribution system
03/11/1993	DE4228027A1 Amplifier-loudspeaker casing with independent energy store - is designed for HI-FI operation in car compartment for high performance.
02/1993
02/10/1993	EP0526979A2 Interactive participation system
01/1993
01/07/1993	EP0521655A1 A loudspeaker cluster
01/06/1993	CN2126532Y Multifunctional imergency amplified communicator with light
12/1992
12/30/1992	EP0520067A1 Improved audio distribution system.
12/30/1992	CN2126493U Microcomputer automatic speakerphone
12/28/1992	CA2072312A1 Audience participation system
12/26/1992	CA2072322A1 Loudspeaker cluster comprising a plurality of splay angle adjustable loudspeaker cabinets, a device for assembling, hanging or stacking the loudspeaker cabinets, and an apparatus for adjusting splay angle between the loudspeaker cabinets
12/23/1992	CN2125893U Hand auto-megaphone condrolled by sound
12/02/1992	EP0516220A2 Electroacoustic amplifier arrangement and microphone arrangement to be used in the electroacoustic amplifier arrangement
12/02/1992	EP0515829A2 Apparatus and method for the processing of acoustical realtime-information
10/1992
10/27/1992	US5159703 Silent subliminal presentation system
10/14/1992	CN1065370A Public address intelligibility system
10/06/1992	US5153914 Sound equipment system
09/1992
09/30/1992	EP0505645A1 Public address intelligibility enhancement system
09/23/1992	CN2117010U Computer repeating microphone
09/15/1992	US5148491 Automatic mixer apparatus
09/09/1992	CN2115636U Transistor andioamplifier
09/09/1992	CN1018232B Multidimensional stereophonic sound reproduction system
08/1992
08/13/1992	DE4104058A1 Control for distribution of electric audio signals to connected loudspeakers - comprises electrical circuit with specific output sides for each loudspeaker connected via integral impedance correction
08/06/1992	DE4202609A1 Controlling reproduction sound level for matching to listening chamber - by regulating loudspeaker signal according to difference between generated and detected auditorium test signal
07/1992
07/28/1992	US5134716 Point of sale audio-visual advertising system
07/16/1992	DE4101156A1 Position location and tracking of objects - using pulsed outputs from infrared transmitters detected by image processing system
07/14/1992	US5131051 Method and apparatus for controlling the sound field in auditoriums
07/14/1992	US5131050 Method and device for generating sound in a hall
07/14/1992	US5131048 Audio distribution system
07/10/1992	WO1992012606A1 Improved audio distribution system
06/1992
06/30/1992	US5125732 Motion picture exhibition facility
06/25/1992	WO1992010917A1 Acoustic device
06/24/1992	CN2108391U Wireless chinese phonetics megaphone
06/24/1992	CN1062254A High voltge large power transistorized amplifier
06/09/1992	US5121426 Loudspeaking telephone station including directional microphone
06/02/1992	US5119428 Electro-acoustic system
05/1992
05/20/1992	CN1061314A High power transistor amplifier
05/19/1992	US5115470 Sound reinforcement system
05/19/1992	CA1301073C Voice enhancer system
05/12/1992	CA1300728C Public address amplifier
04/1992
04/28/1992	US5109423 Audio system with amplifier and signal device
04/28/1992	US5109419 Electroacoustic system
04/02/1992	WO1992005673A1 Polyphonic room with homogeneous sound and installation of the same type
01/1992
01/22/1992	CN2094167U Megaphone for telephone receivers

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