Patents
Sitemap › H04 - Electric communication technique › H04R - Loudspeakers, microphones, gramophone pick-ups or like acoustic electromechanical transducers; Deaf-aid sets; Public address systems › H04R 3 - Circuits for transducers
Patents for H04R 3 - Circuits for transducers (18,190)
12/1990
12/18/1990CA1278086C Sound location arrangement
12/13/1990DE3918654A1 Loudspeaker with filter circuit between separately driven coils - has two moving coils rigidly coupled together in air gap of driver transducer connected to amplifier
12/12/1990EP0401244A1 Radio receiver for vehicles
12/04/1990US4975953 Combined deemphasis circuit and noise blanker
11/1990
11/28/1990EP0399307A2 Autoradio
11/22/1990EP0398595A2 Image derived directional microphones
11/22/1990EP0398536A2 Apparatus for controlling acoustical transfer characteristics
11/20/1990US4972489 For a motor vehicle characterized by a room width
11/15/1990DE3928122A1 Frequency splitter for multi-path loudspeaker system - has analogue sound signals delayed according to transmission delay
11/15/1990DE3915205A1 Loudspeaker housing - has individual auxiliary loudspeakers supported within auxiliary housing units attached to sides of main loudspeaker unit
11/15/1990DE3915204A1 Loudspeaker housing - has auxiliary individual loudspeakers pivoted about axis adjacent edge of front panel
11/13/1990CA1276283C Unidirectional second order gradient microphone
11/08/1990DE4007982A1 Audio reproduction system for several audio signal sources - has tuner, signal, converter, clock pulses generator and digital signal processor
11/06/1990US4969195 Impedance compensation circuit in a speaker driving system
11/01/1990WO1990013215A1 Improved adaptive beam-forming for noise reduction
11/01/1990WO1990012627A1 Memory cartridge for video game machine
10/1990
10/23/1990US4965833 Voice enhancer system
10/23/1990US4965775 Image derived directional microphones
10/18/1990WO1990012476A1 Process and device for distribution of sound among several sound sources
10/04/1990WO1990011669A1 Speaker power matching method and apparatus
10/04/1990DE4007226A1 Adaptive rauschunterdrueckungsanordnung Adaptive rauschunterdrueckungsanordnung
10/03/1990EP0390758A2 A microphone amplifier for contact microphones
10/02/1990US4961226 Stereo electroacoustical transducing
10/02/1990US4961177 Method and apparatus for inputting a voice through a microphone
09/1990
09/26/1990CN2062930U Dl series contactless electronic horn
09/20/1990DE3908402A1 Subwoofer loudspeaker
09/18/1990US4958327 Ultrasonic imaging apparatus
09/12/1990EP0386765A2 Method of detecting acoustic signal
09/11/1990US4956867 Adaptive beamforming for noise reduction
09/05/1990EP0385258A2 Circuitry cancelling potential differences and for signal linearisation
09/04/1990US4955059 Transmitting system
09/04/1990US4953655 Acoustic apparatus
08/1990
08/30/1990DE4003708A1 Ground line impedance elimination circuit - has cable of lower specific resistance than signal lines
08/28/1990US4953212 Auto voice changing apparatus
08/23/1990WO1990009727A1 Process and device for tonal processing
08/16/1990DE3904425A1 Verfahren und vorrichtung zur klangaufbereitung Method and device for sound treatment
08/14/1990US4949384 Driving apparatus
08/09/1990DE3903246A1 Detection and reduction of defects in sound irradiation in headphones
08/08/1990EP0381498A2 Array microphone
08/07/1990US4947434 Electronic attenuator
08/07/1990US4947356 Aircraft cabin noise control apparatus
08/07/1990US4945767 Method and system for controlling ultrasonic probe operation
08/02/1990DE3902338A1 Cross-over network
08/01/1990EP0380310A2 An acoustic analysis device and a frequency conversion device used therefor
07/1990
07/26/1990DE3901745A1 Circuit for a loudspeaker having a number of voice coils
07/24/1990US4944020 Temperature compensation circuit for negative impedance driving apparatus
07/24/1990US4943956 Driving apparatus
07/18/1990EP0378386A2 Electronic gaming device with pseudo-stereophonic sound generating capabilities
07/18/1990EP0377965A2 Combined deemphasis circuit and noise blanker
07/12/1990WO1990007824A1 Electronic audio signal amplifier and loudspeaker system
07/12/1990DE3840551A1 Method and arrangement for improving the reproduction of sound events by loudspeakers
07/11/1990EP0377144A2 Method and device for correcting a distortion of the loudness perception of a reproduced-sound presentation
07/03/1990US4939781 Device for eliminating absolute polarity inversion in a high-fidelity sound reproduction system
06/1990
06/27/1990CN2058795U Antinoise micorphone
06/27/1990CA2006456A1 Control device for movable article and drive circuit therefor
06/26/1990US4937874 Emulated guitar loudspeaker
06/19/1990US4934770 Electronic compression system
06/12/1990US4933921 Signal reproducing apparatus
06/07/1990DE3840707A1 Control circuit for a broadcast receiver
05/1990
05/16/1990EP0368418A1 Device for focussing an ultrasonic beam in three dimensions
05/15/1990US4926139 Electronic frequency filter
05/02/1990EP0366109A2 Method and device for linearizing the frequency response of a loudspeaker system
05/01/1990US4922542 Headphone comfort
05/01/1990US4922535 Transient control aspects of circuit arrangements for altering the dynamic range of audio signals
05/01/1990US4922131 Differential voltage threshold detector
05/01/1990CA1268537A1 Second order toroidal microphone
04/1990
04/25/1990EP0364930A2 Negative impedance driving apparatus having temperature compensation circuit
04/18/1990CN2056300U Earphone socket connector for telecommunication shunt circuit
04/10/1990CA1267720A1 Method and device for electrically powering a transducer used to generate sound and ultrasound vibrations
04/04/1990EP0361445A2 Acoustic apparatus
04/04/1990EP0361444A2 Driving apparatus
04/03/1990US4914707 Balanced vehicular speaker system
03/1990
03/27/1990US4912393 Voltage regulator with variable reference outputs for a hearing aid
03/15/1990DE3929481A1 Noise reduction equipment in speech signal processing system - couples microphones by hierarchical neuronal networks to digital processor
03/14/1990CN1007198B Telephone set equipped for amplified listening and with an anti-larsen device
03/13/1990US4908870 Motional load driver
02/1990
02/28/1990EP0356327A1 Apparatus for picking up sound signals with noise cancellation
02/27/1990US4905290 Howling protective apparatus
02/27/1990US4905284 Audio system for vehicular applications
02/13/1990US4901354 Method for improving the reliability of voice controls of function elements and device for carrying out this method
02/06/1990US4899388 Infrared stereo speaker system
01/1990
01/30/1990US4897879 Multi-way loudspeaker system
01/30/1990CA1265063A1 Methods and means for deafening externally generated noises reaching the eardrum and for improving the clarity of perceived electro-acoustic communications
01/17/1990EP0350652A1 Electrodynamic loudspeaker
01/10/1990CN2051030U Audio equipment with double voice-coil loud-speaker and self phase-reverse function
01/03/1990EP0348396A1 Radio receiver speech amplifier circuit.
12/1989
12/19/1989US4888811 Loudspeaker device
12/19/1989US4888809 Method of and arrangement for adjusting the transfer characteristic to two listening position in a space
12/19/1989US4888807 Variable pattern microphone system
12/12/1989US4887298 Electronic circuit for sensing disconnect or failure of a power output sense line in an audio power system
12/06/1989EP0344545A2 Temperature compensation circuit in a negative impedance driving amplifier
12/05/1989US4885782 Single and double symmetric loudspeaker driver configurations
12/05/1989CA1263608A2 Microphone actuation control system suitable for teleconference systems
11/1989
11/29/1989EP0343691A2 An apparatus for changing a sound field
11/29/1989EP0343675A2 A microphone apparatus for a video camera
11/29/1989EP0343529A2 Driving circuit with control information memory
11/23/1989EP0342782A2 Electroacoustic system with electronic filters
11/21/1989US4882773 Audio microphone system with digital output and volume control feedback input
11/21/1989US4882525 Method for controlling the working frequency of an electro-acoustic vibrating device
11/15/1989EP0191836B1 Movable apparatus for sound wiring and/or visualization
1 ... 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182