Patents
Sitemap › H04 - Electric communication technique › H04R - Loudspeakers, microphones, gramophone pick-ups or like acoustic electromechanical transducers; Deaf-aid sets; Public address systems › H04R 1 - Details of transducers
Patents for H04R 1 - Details of transducers (42,173)
06/1991
06/25/1991US5025885 Multiple chamber loudspeaker system
06/25/1991CA2034090A1 Loudspeaker system
06/22/1991WO1991010243A1 Coil assemblies
06/19/1991EP0432546A2 Piezoelectric transducer unit for telephone sets
06/18/1991US5025474 Speaker system with image projection screen
06/18/1991US5025473 Hemispherical speaker system
06/18/1991US5024407 Adjustable support for loudspeaker
06/13/1991WO1991008657A1 Speaker enclosure
06/13/1991DE3940859A1 Active loudspeaker cabinet lined with metallic screening material - to which connections are made from mains interference suppression filter and casing of tweeter
06/11/1991US5022488 Transducer enclosure
06/11/1991US5022486 Sound reproducing apparatus
06/11/1991US5022100 Apparatus and method for underwater acoustic receiving system installation in diving helmet
06/09/1991WO1991009396A1 Loudspeaker and horn therefor
06/06/1991DE3940193A1 Music reproducing loudspeaker system - has two loudspeakers of different frequency ranges in common housing
06/04/1991US5020630 Loudspeaker and horn therefor
06/04/1991CA1284554C Earmuff apparatus for use with headsets
05/1991
05/30/1991WO1991007859A1 Voice transmission system
05/30/1991WO1991007858A1 Improvements in or relating to audio loudspeakers
05/30/1991WO1991007742A1 Improved audio transducer with controlled flexibility diaphragm
05/29/1991EP0429264A2 Microphone apparatus
05/29/1991EP0429121A1 Loudspeaker system comprising a Helmholtz resonator coupled to an acoustic tube
05/28/1991US5018599 Headphone device
05/28/1991CA1284531C Increased sensitivity piezoelectric hydrophones
05/23/1991DE4036300A1 Adjustable built-in loudspeaker system - allows adjustment independently of external cabinet position which can be built into wall or ceiling
05/22/1991CN1051654A Crystal speaker and manufacturing method thereof
05/21/1991US5018206 Network mounting device for coaxial type speaker
05/15/1991CN2077176U Microphone wire cover connecting structure
05/14/1991US5016228 Sonar transducers
05/14/1991CA1284210C Acoustic transducer
05/07/1991US5012890 Acoustic apparatus
05/07/1991US5012889 Speaker enclosure
05/07/1991CA1283867C Adaptor for coupling plural compression drivers to a common horn
05/02/1991EP0425129A2 Earphoning
05/02/1991EP0424916A2 Magnetically shielded electromagnetic acoustic transducer
05/02/1991DE4030089A1 Cylindrical loudspeaker housing allowing vibrating walls - has curved surfaces so that reflected waves collide reducing standing waves
05/02/1991DE4007440C1 Sound capturing unit for drum - has frusto=conical funnel with large end attached to drum and holder for microphone at small end
05/02/1991CA2029048A1 Public address system
05/01/1991CN2075904U 音响家具 Sound Furniture
05/01/1991CN1012543B Piezoelectric transduce with multiple sensitive coaxial elements
04/1991
04/30/1991US5012457 Aquatic transducer system
04/30/1991US5010977 Acoustic apparatus with plural resonators having different resonance frequencies
04/28/1991CA2027340A1 Earphoning
04/24/1991EP0423858A2 Mounting system to attach a microphone to a wind instrument
04/24/1991EP0423202A1 Headphone with microphone.
04/24/1991EP0423172A1 Active noise reduction system.
04/24/1991EP0423161A1 Passive loudspeaker enclosure for television receiver
04/23/1991US5009281 Acoustic apparatus
04/23/1991US5009280 Acoustic apparatus
04/23/1991US5009232 Extracorporeal lithotripsy apparatus using high intensity shock waves for calculus disintegration and low intensity shock waves for imaging
04/18/1991WO1991006192A1 Soft sonar suspension system
04/18/1991WO1991005445A1 Hand-carried auditory assistance apparatus
04/18/1991DE3933870A1 Controlling microphones supplied with current over cable audio cores - involves adjustment of supply voltage so that magnitude provides control information
04/18/1991CA2067242A1 Soft sonar suspension system
04/17/1991EP0422322A2 Speaker cover grille installation
04/17/1991EP0262145A4 Piezoelectric polymeric film balloon speaker
04/16/1991US5008945 Water-proof speaker unit
04/16/1991US5008944 Loudspeaker system for motor vehicles
04/16/1991US5008933 Automatic sterilizing device of the telephone
04/16/1991US5007707 Integrated sound and video screen
04/10/1991EP0421718A1 Ink drop printhead
04/10/1991EP0421681A2 Electro-acoustic transducer and sound reproducing system
04/09/1991US5007091 Procedure and device for facilitating audiovisual observation of a distant object
04/09/1991US5006055 Apparatus for manufacturing an otoplastic
04/09/1991CA1282711C Optimal shadow omniphonic microphone and loudspeaker system
04/04/1991WO1991004651A1 Transducer enclosure
04/04/1991WO1991004645A1 Vented motorcycle helmet speaker enclosure
04/04/1991WO1991004643A1 Planar speakers
04/04/1991WO1991001544A3 Vehicular sound reproducing
04/03/1991EP0420125A2 Electroacoustic piezoelectric transducer having a broad operating range
04/03/1991CN1012316B Wide-band loudspeaker
04/02/1991US5004105 Packaging arrangement for transporting audio system components to and from an outdoor marine site
04/02/1991US5004067 Cinema sound system for unperforated screens
04/02/1991US5004066 Acoustic apparatus
03/1991
03/26/1991US5003516 Ultrasonic probe and manufacture method for same
03/26/1991CA1282162C Electroacoustic device with broad frequency range directional response
03/21/1991DE3925919A1 Acoustic transducing system with passing loudspeaker - coupled to active speaker in common housing by air movement
03/20/1991EP0417388A2 Body vibrator
03/20/1991EP0155266B1 Loudspeaker structure
03/19/1991US5001763 Electroacoustic device for hearing needs including noise cancellation
03/19/1991US5000286 Modular loudspeaker system
03/13/1991CN2073199U Earphone for preventing sleepiness
03/08/1991WO1991003914A1 Electromagnetic resonant vibrator
03/07/1991WO1991002678A1 Device forming the mouthpiece of a snorkel or a diving regulator hose
03/07/1991DE3936639C1 Permanent magnet arrangement e.g. for vehicle loudspeaker - includes associated oscillatory coil arrangement to drive loudspeaker diaphragm
03/05/1991US4997059 Loudspeaker mounting
03/05/1991US4997058 Sound transducer
03/05/1991US4997057 Method and apparatus of expanding acoustic reproduction range
02/1991
02/28/1991DE3928253A1 Combined sound and lighting device - has loudspeaker and light source in common housing reducing wiring and space requirements
02/27/1991EP0414526A2 Boom microphone
02/27/1991EP0414525A2 Headset cushion
02/27/1991EP0414479A2 High compliance headphone driving
02/27/1991EP0414264A2 Virtual microphone apparatus and method
02/26/1991US4996713 Electroacoustic piezoelectric transducer having a broad operating range
02/26/1991US4996675 Signal sensor insensitive to static pressure variations
02/26/1991CA1280821C Piezoelectric polymeric film balloon speaker
02/25/1991CA2023454A1 Reducing microphone puff noise
02/25/1991CA2023453A1 Headphone cushioning
02/24/1991CA2023142A1 High compliance headphone driving
02/21/1991DE3940615C1 Double diaphragm moving coil loudspeaker - dynamically dampens resonant frequency by cross-coupling second coils of moving coils in opposite phase
02/21/1991DE3927178A1 Loudspeaker box with corrugated cardboard walls - has cardboard in several adhered layers, typically three
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