United States Patent (19)
`Goldfarb et al.
`
`54). APPARATUS FOR THE CREATION OFA
`DESIRABLE ACOUSTICAL VIRTUAL
`REALITY
`
`75 Inventors: Barry S. Goldfarb, Deland; Darren P.
`Ryle, Deltona, both of Fla.; Gary
`McGinnis, Powell; Josh Dickman,
`Knoxville, both of Tenn.
`73 Assignee: BSG Laboratories, Inc., Deland, Fla.
`
`21 Appl. No.: 08/986,712
`22 Filed:
`Dec. 8, 1997
`Related U.S. Application Data
`63 Continuation-in-part of application No. 08/426,822, Apr. 21,
`1995, Pat. No. 5,764,777.
`(51) Int. Cl. ................................................. H04R5/00
`52 U.S. Cl. ........................... 381/301; 381/333; 381/388
`58 Field of Search ..................................... 381/335, 388,
`381/396, 301, 300, 333,334, 332
`
`56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`7/1968 Mitchell.
`3,393,766
`4,015,778 4/1977 Chen et al. .
`4,023,566 5/1977 Martinmaas ............................ 381/388
`4,354,067 10/1982 Yamada et al. ......................... 381/396
`4,450,495 5/1984 Naruki.
`4,602,358 7/1986 Sadan.
`4,654,907 4/1987 Haugaard.
`4,746,166 5/1988 Sadan.
`
`
`
`USOO6075868A
`Patent Number:
`11
`(45) Date of Patent:
`
`6,075,868
`Jun. 13, 2000
`
`9
`
`4,758,047 7/1988 Hennington.
`4,944,019 7/1990 Watanabe ................................ 381/335
`5,147,109 9/1992 Jolly.
`5,177,616 1/1993 Riday.
`5,179,447
`1/1993 Lain.
`5,390,246 2/1995 Gay et al. .
`5,398,992 3/1995 Daniels
`
`FOREIGN PATENT DOCUMENTS
`4-354-906 12/1992 Japan.
`OTHER PUBLICATIONS
`Interactive Speaker Designer, “Common Designer', v.0.03
`(C) 1997, Juha Hartikainen.
`Primary Examiner Vivian Chang
`Attorney, Agent, or Firm-Quarles & Brady
`57
`ABSTRACT
`A portable collapsible seat with an advanced five-driver
`integral audio System is disclosed. The Seat is designed to be
`used in conjunction with a Video Screen to create an
`enhanced “virtual reality” environment. The placement of
`the drivers relative to the user's head, combined with the
`intentionally different bandwidths of Sound produced by the
`different drivers, and the relative acoustical intensities of the
`drivers produces psychologically “gripping effect,
`designed to transport the user away from the reality of the
`actual Surroundings and into the Virtual reality of the Video
`presentation. One of the driverS is intentionally oriented and
`positioned to provide tactilly perceivable vibration through
`the Seat to the user.
`
`26 Claims, 8 Drawing Sheets
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`Jun. 13, 2000
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`1
`APPARATUS FOR THE CREATION OF A
`DESIRABLE ACOUSTICAL VIRTUAL
`REALITY
`
`CROSS-REFERENCE TO RELATED
`APPLICATION
`This is a continuation-in-part of U.S. patent application
`Ser. No. 08/426,822, filed Apr. 21, 1995, now U.S. Pat. No.
`5,764,777.
`
`FIELD OF THE INVENTION
`The invention relates generally audio-visual virtual reality
`Systems, and to Video games and to arcade Video games
`where the player is Seated in a Seat attached to the game
`while playing, and more specifically to Sound Systems used
`with Video games, virtual reality apparatus, and personal
`Video Stations.
`
`15
`
`BACKGROUND OF THE INVENTION
`Over the last decade, Video games have been a popular
`form of entertainment for consumers. AS the computation
`necessary to generate advanced full-motion graphics has
`Steadily become cheaper, and algorithms for generating
`imagery on the fly have become more well developed, the
`average consumer has continued to make regular expendi
`tures of discretionary income to upgrade home video game
`Systems, and play the latest arcade Video games. One of the
`draws of arcade Video games and advanced home video
`games is the level to which the realism of the images enables
`the player to escape from the real world for a time and enter
`the fantasy World of the game. The graphics of top arcade
`games have gone from Simple two-dimensional
`representations, to three dimensional representations with
`complex Shading and textures, and the laws of physics well
`represented in how the three-dimensional characters and
`objects in the games interact.
`AS the Video imageS produced by top Video games have
`taken Staggering leaps forward in complexity over the last
`ten years, the Sound tracks of these games have also
`advanced considerably, though not as much as the Video
`images have advanced. This is partly due, perhaps, to the
`lack of Significant advancement in the designs of the Speaker
`Systems that deliver the Sound to the consumer who is
`playing the game. Most speaker Systems in arcade Video
`games remain quite similar to those of 10 years ago. These
`are either simple monaural Speaker Systems, or simple Stereo
`Speaker Systems, usually mounted in the cabinet of the Video
`game console, which is usually positioned in front of the
`consumer playing the game.
`AS the Sound tracks for these video games improve, they
`are getting closer to the level of quality found in the Sound
`tracks of today's box office hit movies. These movies often
`contain amazing Special effects. A Sound track which creates
`an acoustic experience which "grips' the audience can be a
`key factor in transporting the audience into the artificial
`reality being created by the movie. In this vein, top-of-the
`line Video games will be using Sound more and more to
`create the reality for the player of the game. AS this trend
`continues, it is likely that audio Systems for Video games are
`likely to continue to improve in quality. Let's take a look at
`the nature of the “quality” that home audio System designers
`have Striven for Over recent decades.
`The reproduction of music, with desirable psycho
`acoustical characteristics (Such as might be experienced in a
`concert hall listening to a live performance) has been the
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`objective of many in the audio industry for years. The
`modern pursuit of this goal has included implementations
`utilizing digital Signal processing for the reconstruction of a
`Sound field by measuring the acoustic response of the field
`and then modifying the input to an array of loudspeakers to
`produce the appropriate Velocity and pressure within the
`fluid medium.
`Some hold that audio systems should be designed for the
`“exact reproduction of a Sound field that might be experi
`enced by a listener in a concert hall. The exact reproduction
`of a Sound field can be approached one of two ways. In the
`first way, a recording of the Sound experience to be repro
`duced may be made on a binaural recording device which
`mimics the size and shape of a human head (including the
`ears). When played back through headphones, Such a record
`ing can be Strikingly lifelike, with much of the Spatial
`(directional) cues preserved. The disadvantage of this type
`of recording is that it is So highly optimized for headphone
`play-back; it does not Sound as good as a “regular Stereo
`recording when played back through speakers which arent
`right next to the listener's head. Another disadvantage of
`headphones is that their use may be cumberSome or imprac
`tical in Some applications, and headphones used in public
`applications (such as in CD Stores or arcades) are prone to
`reliability problems.
`The Second way that one can approach the reproduction of
`a Sound field is to produce a Sound field with multiple
`Speakers placed at different points in Space, and fed different
`Signals (hereinafter referred to as a “multi-channel” audio
`System). Stereo is the simplest Such commonly employed
`approach. Such psycho-acoustic parameters as perceived
`“depth”, “spaciality”, “color”, and “timbre” are generally
`agreed to be much improved in a stereo Sound System, as
`compared with a monaural Sound System. Driver character
`istics Such as linearity and frequency response also affect the
`perceived quality of the Signal.
`Sound Systems with more than two speakers also exist
`(though they are not as widely used as simple Stereo). Such
`systems include Dolby Surround-Sound (used in theaters),
`and earlier attempts at "quadraphonic' Standards. The prob
`lem in designing multiple-speaker Systems beyond Simple
`Stereo is choosing a trade-off in the number of transducers,
`the placement of those transducers, the design of those
`transducers, and the Signals fed to those transducers to
`economically produce a “desirable' psycho-acoustical
`effect.
`Trying to recreate a standard audio bandwidth (20 HZ-20
`kHz) Sound field to arbitrary accuracy throughout a room is
`a totally impractical problem. AS detailed in a publication by
`Nelson, P. A., 1994, "Active control of acoustic fields and
`the reproduction of Sound,” Journal of Sound and Vibration,
`177(4), pp. 447-477, to identically reproduce a sound field
`with an array of transducers over a frequency range extend
`ing from 20 Hz to 10 kHz and for a sphere of 10 m diameter
`would require over 1 million individual Sources.
`Fortunately, the human auditory System is not measuring
`“everything” about the sound field. Some is known about
`what "key things contribute to perceptions (perceptions
`Such as “this Sounds real, and this doesn't'), and a lot is
`Still not known. An exciting opportunity exists in the field of
`audio to discover and design Systems which, while much
`Simpler than the above described one million transducers,
`provide highly desirable psycho-acoustical effects at reason
`able prices, and are thus valued by consumers.
`One cost-Saving innovation which has become quite
`widespread in modern Stereo Systems is the addition of a
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`6,075,868
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`3
`third “subwoofer transducer to the original stereo model.
`The Sub-woofer produces low-frequency Sounds, usually
`below about 250 Hz. The human auditory system is not good
`at determining the Source direction of Such low-frequency
`Sounds. Thus one transducer may be used as effectively as
`two, an the Sub-woofer transducer may be placed anywhere
`in the room. In typical musical Selections, these low fre
`quencies account for most of the power that a loudspeaker
`Set requires. They also account for most of the distance of
`cone-motion in loudspeakers. By removing the low frequen
`cies from the Stereo Speakers, cone motion, and its associ
`ated nonlinearities (which cause distortion) are reduced. All
`these factors together allow the Stereo speakers (in a System
`utilizing a Subwoofer) to be manufactured in Smaller, less
`obtrusive enclosures, with cheaper components, for leSS
`cost. The consumer gets a higher quality, more aesthetically
`pleasing System, for leSS money.
`Within stereo systems (with or without sub-woofers), the
`mid and high frequencies are often produced by Separate
`transducers in the same cabinet (so-called “midrange' driv
`ers and “tweeters”). While often not necessary from a
`distortion perspective, the splitting of mid and upper-range
`frequencies between two transducers is often desirable from
`the Standpoint of obtaining a flat frequency response. Mid
`range drivers often have numerous high frequency
`25
`resonances, at which the amplitude of Sound produced
`changes drastically. This produces a Sound of less desirable
`quality. Another problem with mid-range drivers at high
`frequencies is that they typically produce widely varying
`Sound intensities in different directions, thus, depending on
`where the listener is in the room (worse yet, if the listener
`is moving in the room) the listener may hear inconsistent or
`annoying quality variations from the Speakers.
`In the past ten years, Signal processing, and in particular,
`digital signal processing has allowed for the most significant
`breakthroughs in the quest for more psycho-acoustically
`pleasing Sound reproduction. The quest for “accurate” repro
`duction of Sound is ironic in Some ways. Many have been
`assuming the need to accurately reproduce Something, yet
`concert halls with the same (accurate, live, “real') sources in
`them have vastly different perceived qualities, even with no
`distortion. Taking this into account, one could hold that an
`ideal audio System could create new realities (or acoustic
`environments), not just reproduce known ones. Some of
`today's digital Signal processing units have taken a cut at
`creating part of the reality (as the concert hall does). Digital
`Signal processing audio units cannot, however, overcome
`Some of the basic physical limitations imposed by the
`Speakers we attach to them, Such as the physical positions of
`the speakers in the room, and their directionality (radiation
`patterns) at different frequencies.
`We are a Society undergoing a paradigm shift in our
`culture regarding entertainment. Today's movies and Virtual
`reality games take us well beyond the thirst for reality in
`reproduction, into a thirst for things beyond what are “real',
`the thirst for new experiences which can be created. Musi
`cians electronically create instruments that do not exist,
`which have pleasing musical characteristics. Special effects
`experts create entire visual worlds that do not (an indeed in
`Some cases cannot) exist, and people pay higher and higher
`prices to experience these creations. Many of these creations
`put the observer in places where he or she cannot normally
`be (“in the experience”, So to speak), Such as Standing next
`to a Tyrannosaurus Rex as it eats. Someone. The desire here
`is for the new, the vivid, the “more than real”, but definitely
`not just "accurate reproduction of Something previously
`experienced'.
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`As the demand for the ability for us to “enter the expe
`rience’ grows, a significant market will form for in-home
`Systems which can provide this “more than real' entertain
`ment. New acoustical Sound production paradigms (not just
`Sound reproduction, because we want to make things "more”
`than real) will be in demand.
`It is an object of the present invention to provide an
`improved multi-channel audio System which, when playing
`today's film and Video game Sound tracks, provides a more
`involving “gripping psycho-acoustical experience for the
`listener, transporting the listener more effectively into the
`virtual “reality” of the film or video game. It is a further
`object of the present invention to provide an improved
`multi-channel audio System which is Superior to present-day
`Stereo and other multi-channel audio Systems, in Such
`psycho-acoustical dimensions as "timbre”, “color,
`“spatiality”, and “depth”. It is a further object of the present
`invention to provide an aesthetically pleasing, ergonomi
`cally Superior multi-channel audio System. It is a further
`object of the invention to provide a multi-dimensional
`acoustical audio System that combines the Selection of
`transducers, the placement of those transducers and the
`Spectral Separation of frequency to the transducers to opti
`mize the psycho-acoustical effect to the user. It is a further
`object of the invention to provide the psycho-acoustical
`experience to the user with a focus on the binaural auditory
`System and tactile Sensory System of the user and not the
`audio source. It is a further object of the invention to provide
`an easy-to-Set-up, easy-to-store, portable Seat for use with
`Video games and the like, with integral Sound and/or vibra
`tion which provide an enhanced virtual reality experience.
`SUMMARY OF THE INVENTION
`The present invention offers a quantum leap forward in
`the psycho-acoustical environment that can be created for
`the player of a Video game, or "virtual reality” game. When
`using a System according to the invention, the user is
`presumed to be seated in a Seat integral to the System. A
`common use of the System would entail Setting up the
`apparatus as a viewing and listening Station in which to Sit
`and operate a Video game or watch a video on a Screen Set
`up in front of the apparatus and the user.
`According to the invention, an apparatus for creating an
`acoustical virtual reality in connection with an audiovisual
`entertainment, Such as computer Video games, includes a
`Seat having a Seat back and a Seat base connected along a
`joint line and a plurality of acoustics drivers, preferably
`loudspeakers, at least Some of Said loudspeakers being
`positioned on Said Seat Structure and arranged at least to the
`left and right of the Seating area with one speaker centered
`forward of the Seating area.
`The positions of the three Speakers can define a triangle
`wherein the line between the left and right Speakers and a
`line between one these Speakers and the third, central
`Speaker form an angle of greater than 45 degrees.
`The apparatus can further include a Sub-woofer for pro
`ducing signals less than 100 Hz. The subwoofer is preferably
`mounted in the back portion of the seat with its axis of
`motion transverse to the Support Surface for the user's back,
`and particularly his lower lumbar region. The Subwoofer is
`preferably dual-ported to the Sides of the Seat back, proxi
`mate the height of an average user's ear level.
`The apparatus can also include a high frequency device
`for producing Signals above 16 kHz. The high frequency
`device is preferably placed above the left and right loud
`Speakers and behind the user's head. Thus, the high fre
`quency device can be centrally placed along the top of the
`Seat back.
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`The left and right loudspeakers can be mounted on wings
`extending from the Sides of the Seat base. These speakers are
`preferably mounted facing upwardly through apertures pro
`Viding circular deflectors. The central loudspeaker can be
`Similarly mounted upwardly near a front end of the Seat base
`and equipped with a circular deflector.
`According to another aspect of the invention, the appa
`ratus provides a collapsible Seat having at least a low
`frequency vibrational transducer or loudspeaker for tactile
`Signal generation. The collapsible Seat preferably is also
`equipped with other loudspeakers for generating a Sound
`field as well. The Seat can include an internal amplifier, and
`optionally, audio intensity limiters.
`The Seat construction preferably includes a hinged assem
`bly including a lower extension of the Seat back that Serves
`as a carrying handle during Storage and transport and a
`resistive Support in the open position against the user's back
`leaning. The hinge can include a detent latch for Securing the
`Seat in both the open and the closed position. The Seat
`housing is preferably constructed to port the Subwoofer with
`a dual tuned port System. The lower Seat base can also be
`designed to port the back wave of the central loudspeaker to
`lateral sides of the Seat base.
`Thus, the apparatus of the invention provides a Seated
`environment for creating an acoustical virtual reality to
`enhance audio visual entertainment in connection with Video
`games and the like. The System not only provides enhances
`audio but also tactile Signals to the user.
`
`BRIEF DESCRIPTION OF THE DRAWING
`FIG. 1 is a perspective view of an embodiment of the
`invention in use with a computer-based video gaming Sys
`tem,
`FIG. 2 is a further perspective view of the embodiment
`shown in FIG. 1;
`FIG. 3 is a perspective view of the rear section of a seat
`back of the embodiment of FIG. 2;
`FIG. 4 is a perspective view of the front, mating Section
`for the seat back section of FIG. 3;
`FIG. 5 is a perspective view of the lower section of a seat
`base of the embodiment shown in FIG. 2;
`FIG. 6 is a perspective view of the upper, mating Section
`for the seat base section of FIG. 5;
`FIG. 7 is a perspective view of the embodiment shown in
`FIG. 2, shown in a closed configuration; and
`FIG. 8 is an exposed perspective view of the interface of
`the rear Seat back Section and the lower Seat base Section,
`illustrating the internal features of a hinge latch mechanism
`according to the invention.
`
`DETAILED DESCRIPTION OF INVENTIVE
`EMBODIMENTS
`The invention is directed to a device for creating an audio
`and tactile virtual reality environment for a user Seated on
`the device to enhance the experience in audio-visual
`entertainment, Such as playing a video game or viewing a
`motion picture.
`Referring to FIG. 1, a Seating apparatus 10 according to
`the invention can be mounted by a user 12 for use during the
`playing a Video game through a computer 14, on for example
`a stand 16, with associated viewing on a video monitor 18
`or the like. The user 12 can interact with the computer 14 or
`Video game through hand controls 20 in known manner. The
`apparatus 10 Supplies audio and preferably tactile signals to
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`6
`the user 12, as discussed more fully below. The input signals
`from the computer can be provided through a cable 22 to the
`apparatus 10.
`Preferred embodiments of the present invention makes
`use of both spatial signal processing (the placement of
`transducers in known spatial relationships with respect to the
`listener), temporal Signal processing (the Selection of the
`range of frequencies reproduced by each transducer in the
`System), power balancing (the Selection of the relative
`loudness of the Sounds the listener hears from each
`transducer), and vibrational coupling to create a multi
`dimensional (the Spatial dimensions, the temporal
`dimension, the power-balancing dimension, and the tactile
`dimension) acoustical audio System with desirable pSycho
`acoustical effects. The System has been designed to produce
`a Sound field optimized for perception through the process
`by which the binaural auditory System (human hearing)
`processes Sound, as opposed to being designed to produce a
`certain frequency response at a microphone placed Some
`fixed distance on-axis from a speaker in an anechoic envi
`ronment as in conventional loudspeaker performance assess
`ment. The result is an increase in the perceived “width” and
`“depth” of the “Sonic image” and an increased the “sweet
`spot” well beyond those perceived with normal stereophonic
`Sound reproduction.
`The combining of both Spatial Signal processing, temporal
`Signal processing, and power balancing in the present inven
`tion provides Some of the advantages available through
`Digital Signal Processing (DSP), and allows the realization
`of many psycho-acoustical effects not available through
`DSP.
`Because the present invention is designed for perception
`by the binaural auditory System, it is appropriate to review
`this biological System here. Binaural hearing is required to
`physically locate stimuli in the real world. There are two
`basic methods by which the location of a Sound Source is
`determined by the binaural auditory System. Each is distinct
`and has an effective bandwidth of operation. Firstly, the
`interaural time difference (ITD) in the arrival of a sound
`wave at each respective ear can be used to determine the
`direction from which the sound emanated. At relatively low
`frequencies, below 1500 Hz, the wavelength of the sound
`wave is greater than the characteristic dimension between
`the ears (approximately 0.2 m for a typical person). Thus, a
`distinct time delay in the propagation of the Sound wave can
`be resolved. While this method of resolving the direction can
`be effective up to 3000 Hz, it has limited accuracy between
`1000 Hz and 3000 Hz as the acoustic wavelength decreases.
`At frequencies greater than 3000 Hz, the primary method of
`resolving the direction of a Sound Source is based upon the
`interaural intensity difference (IID). At higher frequencies
`and decreasing acoustic wavelength, Sound waves are par
`tially blocked by the effective “baffle” created by the head if
`the Source is not positioned directly in front of the listener.
`Thus, variations in Sound intensity presented at each ear help
`in discerning the location of a Source at relatively high
`frequencies.
`In reverberant, enclosed, Sound fields, the Sound originat
`ing from a Source will bounce off the walls Several times in
`various directions until it decays sufficiently to be inaudible.
`However, for transient acoustic waves, extensive testing has
`shown that the direction from which a Sound first arrives is
`perceived to be the location of the source even if the
`reflected (delayed arriving signal) is larger than the first
`arriving signal (Moore, 1989).
`Oddly enough, the frequency range in which directional
`information is difficult to discern by either ITD or IID is in
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`7
`a range of 1 kHz to 3 kHz where the sensitivity of the ear to
`Sound is quite high. Accordingly, a single mono Sound
`Source placed in front of the listener with an upper frequency
`limit of approximately 3 kHz and will not have a dramatic
`effect on the perceived direction of the Sound over the
`audible range, but can be effectively used to “create the
`center Stage'.
`At higher frequencies, it is imperative to have both left
`and right Stereo Signals if Stereophonic imaging is desired. In
`fact, based upon the IID method of detecting the position of
`a Sound Source, the optimal location of the Stereophonic
`transducers producing Sound in the approximately 900 Hz to
`16 kHz bandwidth are at opposite sides of the listener to
`maximize the IID. At low frequencies, the acoustic wave
`length is So long that a listener cannot accurately resolve the
`direction of the Source (because the Sound heard at either ear
`is nearly in phase), so a sub-woofer (0 to 250 Hz bandwidth)
`can be placed in any position relative to the user to eco
`nomically reproduce the low-frequency component of the
`Sound (which usually requires the most power and produces
`the most driver cone excursion). Finally, a single mono high
`frequency device (producing frequencies from approxi
`mately 4-6 kHz to >20 kHz) can be located near the rear of
`the listener or centrally overhead to achieve the effect of
`greater reverberation. The pinna (outer ear) serves to dimin
`ish the sound by virtue of reflection and diffraction at high
`frequencies when the Sound wave is presented from behind.
`Acoustic waves reflected in a reverberant field also impinge
`the ear at reduced intensities than that of the original wave.
`Thus, placing a higher frequency driver at the rear of the
`listener can achieve the psycho-acoustical impact of a more
`“live” acoustic field as opposed to the more complex use of
`full-bandwidth transducers and Signal processing to achieve
`the same desired effect.
`Traditional acoustical priorities Such as low distortion and
`adequate frequency response, together with new objectives
`involving psycho-acoustical qualities Such as “spatiality”
`have been taken into account by the design of one embodi
`ment of the multi-dimensional acoustical audio System Set
`forth herein. Conventional audio speaker performance Speci
`fications lose meaning here because the Sound System pro
`Vided by this invention is designed to be perceived through
`the binaural auditory System, not a microphone positioned at
`a fixed distance from a speaker mounted in a baffle. Quality
`transduction devices are used in this System to minimize
`distortion. Within the present invention, the relative sensi
`tivity of each transducer is not as important as is the location
`of each device relative to the listener, coupled with the
`asSociated temporal filtering which is unique to the position
`of the device relative to the listener.
`In one embodiment according to the invention, the appa
`ratus comprises a collapsible portable chair or Seat with an
`integral audio system. While in collapsed form, all drivers
`and amplifiers of the audio System are internal to the unit.
`When in use, Some components of the audio System remain
`internal to the chair, and Some are deployed in a fixed spatial
`relationship to the seat (and the listener Seated there).
`In addition to the placement of the transducers in the
`System, there are certain aspects of the mounting of the
`transducers and the design of the individual transducer
`enclosures which provide key improvements in the quality
`of the perceived Sound field. The Side transducers are
`preferentially oriented vertically (with their radiating Sur
`faces parallel to the horizontal plane), and their enclosures
`preferentially include acoustic reflectors Suspended in front
`of the transducers, to give a more desirable acoustic disper
`Sion pattern acroSS the range of frequencies produced by the
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`15
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`35
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`6,075,868
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`8
`transducer. This circularly Symmetric reflector ensures that
`Sound emanates with equal intensity in all directions in the
`horizontal plane. This circularly Symmetric pattern may be
`combined with placement of a reflecting Surface on the
`opposite Side of the Side Sound Sources from the listener.
`This spreads out the apparent Side Sources from the point of
`View of the listener, because Sound energy may be received
`from all over the reflective Surface. The apparent spreading
`of the Source can result in an improved psycho-acoustical
`effect.
`Referring to FIG. 2, the apparatus 10 is preferably con
`Structed as a portable, collapsible Seat 24 with integral and
`attached audio components. The Seat 24 includes a base 26
`connected to a back 28 through a hinge assembly 30. The
`base 26 is constructed for placement on the floor, but can
`also be mounted on a pedestal 32 for raised Seating more in
`the manner of a chair. The seating area 34 of the base 26 and
`the Support area 36 of the seat back 28 can be equipped with
`cushioned Surfaces, Such as by foam or rubberized pads, to
`provide comfortable Seating to a user.
`The System preferentially includes at least one central
`audio loudspeaker 38 placed substantially in front of the
`user. The central audio loudspeaker 38 is preferably posi
`tioned forward of the seating area 34 near the front edge 40
`of the Seat base 26, facing upwardly, and may in Some
`embodiments be placed Separately from the Seat 24 closer to
`the Video Screen being viewed. The central audio loud
`Speaker 38 preferably has an input filtered to range in
`frequency from Substantially 150 Hz to no more than 10
`kHz. In a preferred embodiment, the maximum input fre
`quency to the central audio loudspeaker 38 is limited to 6
`kHz. The central audio loudspeaker 38 can be any of a
`variety of loudspeakers capable of performing in the fre
`quency range Specified but is preferably Selected to have an
`optimal Sensitivity and performance in the above input
`range.
`The embodiment for immersive observation further
`includes a left audio loudspeaker 42 placed directly to the
`listeners left when Seated, and a right audio loudspeaker 44
`placed in directly to the listener's right. The left audio
`loudspeaker 42 and the right audio loudspeaker 44 should be
`Spaced far enough from the listener's ears when Seated So
`that the distance from the listener's head to each of these
`loudspeakers 42, 44 is large compared to the normal amount
`that the listener's head might move forward, backward, and
`from Side to Side during the normal playing of a Video game
`or watching of a movie.
`While it is preferred that the left audio loudspeaker 42 and
`the right audio loudspeaker 44 be located directly to the
`sides of the observer, it is within the scope of the invention
`that the loudspeakers may be forward or rearward of these
`exact positions, but preferably these Speakers are Symmetri
`cally placed, at positions no more than 50 degrees off to the
`front or rear of an imaginary line passing through the
`listener's ears when Seated.
`The left audio loudspeaker 42 and the right audio loud
`