MXPA00009111A - In-home theater surround sound speaker system - Google Patents

Abstract

An apparatus for realistically reproducing sound includes a front speaker (20) located in proximity to the video image for providing acoustic output based upon a summation signal of the component left and right (L + R) channels of the audio signal. A rear speaker (26) located to the rear of the viewing area provides acoustic output based upon a difference signal, (L - R or R - L), between the left and right channels. The left and right side speakers (22, 24) are located to the respective left and right sides of the viewing area. The left side speaker (22) provides two acoustic outputs in accordance with a band limited left channel signal and a band limited difference signal. The right side speaker (24) provides two acoustic outputs in accordance with a band limited right channel signal and a band limited difference signal. Band limiting substantially filters out frequency components below a predetermined threshold.

Description

PERIMETRIC SOUND HORN SYSTEM FOR HOME THEATER This application corresponds to a continuation-in-part of the US patent application. Serial No. 08 / 707,101, filed September 3, 1996, which is a continuation-in-part of the U.S. Patent application. Serial No. 08 / 525,364, filed September 7, 1995, Patent No. 5,708,719. BACKGROUND OF THE INVENTION Technical Field This invention relates generally to the reproduction of stereophonic sound and more particularly to the reproduction of stereophonic sound associated with a video image, such that dialogue is located in the video image and effects are reproduced. of sound and environment in a way that immerses the listener in a realistic three-dimensional sound field. Discussion In the past, numerous monophonic and stereophonic sound systems have been developed in an attempt to achieve high-fidelity sound reproduction. Initial efforts restrict the concept of high fidelity to playing monophonic audio signals. These early efforts focused on producing a speaker enclosure that meets the performance criteria defined by measurable acoustic characteristics such as frequency response, distortion and dynamic range. The speakers include an enclosure that contains one or a number of acoustic transducers and crossover networks 5 intended to reproduce the entire range of audibility frequency. As an example of this multiple transducer and crossover configuration, a three-way speaker design includes a bass driver transducer, to reproduce low frequencies, a range transducermeans to reproduce mid frequencies and a transducer. { flff Tweeter to play high frequencies. The crossover network described above, mixes the acoustic output of the horn transducers to achieve good tonal balance characterized by a transitionuniform acoustic output from one transducer to another. One way to achieve this is a symmetric crossover network that functions as a filter to ensure the response decline of a transducer as the frequency increases across the transition region is a• 20 image in the mirror of the increase in response of an accompanying transducer that reproduces the adjacent higher frequency sound band. Proper implementation of this design approach requires that the combination of crossover networks and transducers do not introduce audible artifact(an unnatural sound quality) resulting from frequency response irregularities or phase cancellation effects that potentially result in housing a multiplicity of transducers in a speaker enclosure. Early attempts at high fidelity through monophonic audio signals and three-way crossover networks eventually resulted in the reproduction of stereophonic sound. The first stereophonic systems used a pair of spatially identical, high fidelity speakers to reproduce two audio signal channels. This spatial distribution for two-speaker venues is fundamental to the concept of stereo sound reproduction. A stereo image results when the acoustic output of the pair of speakers melts into a stereo image perceived as a horizontal sound panorama. This sound panorama creates in the listener a stereo sound image that spans the space between the two speaker locations. An appropriate stereo perspective results for a listener placed on an axis between the two speakers and perpendicular to the plane of the speakers. Most of the speakers used in stereophonic systems project sound on a direct route from the speaker to the listener or listener, referred to as direct radiation. In an attempt to widen the stereo image, designers have employed pairs of speakersaa ^ Atfitai iii that radiate a combination of direct and reflected sound. This configuration expands the stereo image beyond the space between the two speakers. Some more contemporary stereo sound system designs use three-piece sub-satellite speaker systems where a combination of bass subwoofer and a pair of satellite speakers replace the pair of conventional full-range speaker enclosures described here previously. In these three-piece speaker systems, the satellite speakers reproduce a wide spectrum of medium and high frequency sounds, while the base unit reproduces only very low frequency sounds. Restricting bass reproduction to the bass subwoofer unit allows satellite speakers to be relatively small in size compared to traditionally large stereo speaker cabinets, whose large size is designated by large transducers and enclosures required to achieve good bass response. Many consumers prefer this smaller satellite speaker structure over the more traditional pair of speaker enclosures across the range. The base unit can be placed outside the view and the satellite speakers blend more easily with the decoration of the room. However, other consumers still see these boxes of satellite horns somewhat smaller, as imperceptible and difficult to incorporate into the domestic scenario in a discreet way. Despite the improvements in total sound quality that are provided even by the most sophisticated systems, be it a pair of stereo speakers or a three-piece sub-satellite system, many consumers believe that contemporary sound systems lack the sense of sonic realism associated with live sound. Each sound reproduction system, while complying with criteria of quantitative acoustic performance with respect to frequency response, distortion and dynamic range, can subjectively evoke a wide range of listening or listening perceptions of sonic realism from a qualitative point of view. Some systems determined for more realistic sound have also found that they create a sound of space in the reproduced sound. This determination has provided the basis for extensive developments in the field of acoustics in order to achieve an improved spatial quality for reproduced sound, while avoiding the introduction of sound artifact that can deteriorate the total sonic experience. The three-piece sub-satellite speaker system described above extends the concept of spatially distributing horn components such as a stereo pair of speakers. The concept can still be further extended by spatial distribution of a substantial number of point sources to reproduce sound in a listening or auditory environment to further increase the perceived spatiality or amplitude. While adding a multiplicity of spatially distributed point sound sources can increase the perfection of space or amplitude it can also produce an exaggerated spatial presentation that lacks realism.

This reproduction of unnatural sound often causes the listener to experience acoustic fatigue. In this way, the improved amplitude must be balanced with the perceived acoustic realism of the resulting sound field in order to fully satisfy the listener. 15 This balance is particularly important in sound systems for home theater, where the acoustic requirements in this application differ from those for sound reproduction of stereo music.ß The key objectives for a theater sound system inhomes are: (1) establishing a convincing surround sound acoustic atmosphere based on the environment and sound effect audio systems captured on the sound track; (2) maintain a panorama of stereo image sound in front of the viewer; and (3) reproduce dialogue thatis located on the video screen for all viewers in the room. In essence, satisfactory acoustic performance results when the listener is immersed in a sound field that has a three-dimensional spatial quality that is perceived as authentic in relation to the visual presentation on the video screen. Initial attempts to produce a home theater sound include placing a pair of traditional speakers on either side of a centrally located video display. These systems improve on the sound of the speakers included within the typical television set. However, the performance of these systems is determined to be unacceptable in the market for at least two reasons. First, listeners located outside the center line between the two speakers will not place the dialogue on the screen (ie they will perceive the dialogue as coming out of the screen only). The dialogue is typically recorded the same on both left and right channel signals. The location of the dialogue will be at a point equidistant between the two speakers for a listener on the center line between the speakers. As one listener moves off the centerline, it will move closer to one speaker and further away from the other. The location of the dialogue will move to the direction from which the first signal that arrives originates. This will be the nearest speaker. The dialogue is reduced to the nearby speaker as a listener moves off the axis. The location of the dialogue will be shifted from the location of the video image to off-axis listeners, and the distribution will be destroyed that the charas on the screen 5 are in fact speaking to listeners located off-axis. Secondly, a pair of stereo speakers located on either side of the visual display confine the sound field to the space in front of the listener, in the plane of the speakers. In this way, there is no sense of immersion - asense that sound events occur alongside listeners as well as in front of the listener.Many systems have been designed in an attempt to remedy these deficiencies.For example, US Patent No. 3,697,192 issued to Hafler discusses employment fromenvironment recovery technology. Hafler uses the fact that the surround sound information receives virtually all the stereo audio signals either music recordings or the track of a video program material and can be recovered. Recovery resultsto obtain the difference signal between the left and right channel (L-R) leaving substantially only the ambient portion of the signal. This left-minus difference signal (L-R) reproduced by speakers placed at the back of the listening room, providesthe recovered surround sound information.

Another sound system for previous alternating home theater added to an additional center channel to reproduce a leftmost right-most signal (L + R) to improve the sound reproduction quality of 5 dialogue. The center channel was combined with rear sound speakers that reproduce a left minus right (L - R) signal, similar to the environment recovery speakers described above. An example of these systems have been developed by DolbyLaboratories under the name DOLBY SURROUND. ^ The central speaker to reproduce the signal (L +R) as incorporated into the DOLBY SURROUND system, improved on the convenient location effect of dialogue, for off-axis listeners. However, the reproduction ofcentral channel (L + R) does not completely solve the problem of displacement between the auditorium and the visual images for off-axis listeners. These systems still suffer from localization errors for dialogue (and other^ fe signals coded in the sum signal) due to thepassive decoding schemes such as DOLBY SURROUND are only able to achieve a maximum adjacent channel separation of 3 dB, where adjacent channels are defined as center and right, center and left, left and perimeter, right and perimeter). AThe difference of 3 dB between the dialogue in the central channel and the dialogue in the left and right channels is not enough to confine the location to the location of the central channel speaker for all the positions of the members of the audience through a room of• 5 typical or typical auditorium listening. The location still moves to the nearby speaker for off-axis listeners. Making the dialogue crush to the nearby speaker is common to all passive decoder systems of the prior art. 10 In an alternative approach to the DOLBY j SURROUND systems, a T-configuration assembly proposed by thePatent of the U.S.A. No. 4,612,663, issued to Holbrook, provides perimeter sound by passively decoding stereo signals. The T configuration includesleft and right speakers that reproduce the respective left and right signals, a third speaker that reproduces the difference signal (L - R) placed halfway between and in the plane of the left and right speakers.^^ right, and a fourth speaker that reproduces the signal ofdifference placed after the listener. However, this approach fails to maintain a rational sonic image in situations where the stereo signal temporarily has left or right predominant channel energy and also fails to avoid the perception of the emanating dialoguefrom the near left or near right speaker.

Another system that uses difference signals (L-R) and (R-L) can be found in the U.S. Patent. No. 5,027,403 granted to Short and collaborators. Short discusses using front-facing left and right channels to provide sound output in the listener's direction. Short also discusses directing the base (L + R) signals backwards from the general plane of the video observation area. Short also discusses directing the signals (L - R) and (R - L) backward or sideways from the general vicinity of the video image. However, Short has the disadvantage that all the sounds emanating from the speakers emanate from the video image. This radiation of substantially planar sound does not completely provide the environment in effect with perimetric sound. Another example of a system having speakers arranged in a generally planar configuration can be found in U.S. Pat. No. 4,497,064 granted to Polk. Polk also discusses having left and right main speakers and additional sub-speakers placed in proximity to the main speakers, to provide the listener with an expanded acoustic image during stereophonic sound reproduction. However, Polk 'maintains specific system-limiting requirements, including that the speakers are equidistant from the listener in order to ensure the arrival of the sound to the listener within a certain period of time. Polk also discusses high pass filtering of an inverted version of a main horn signal for• 5 send output from the opposite side sub-horn. The high-pass filtering cancels the opposite side main speaker component that would otherwise reach the listener's ear on the filtering side. However, high-pass filters are not aimed at canceling componentslow frequency to maintain the location of voice information to a video image. Polk too• specifically requires that all speakers in the system remain substantially in the same plane and radiate in the direction of the listener. The Polk systemNor will it be able to keep the location of program material recorded equally on the left and right channels to the area centered between the two listeners separate from the axis. The location of these signals will move to the nearby speaker for listeners outside ofaxis. Examples of non-planar horn configurations include U.S. Pat. No. 4,443,889 granted to Norgaard. Norgaárd discusses the use of a left front speaker and a right front speaker to reproduce thestereo signals left and right channel respectively.

Norgaard also discusses the use of a difference signal (L - R) through a rear speaker to create an ambience signal. However, among other things Norgaard does not consider combining a sum signal (L + R) through a central speaker to better locate the image in the video image. The patent of the U.S.A. No. 5,181,247 granted to Holl discusses similar concepts regarding the use of difference signals (L - R) and (R - L). However, Holl does not illustrate the use of a single speaker to output an addition signal (L + R). Nor does Holl suggest limiting the signal power to the ambient speakers in band. The patent of the U.S.A. No. 4,819,269 given to Klayman, discusses radial sound based on a sum signal in a limited scattering pattern and radiant sound based on a difference signal in a broad scattering pattern. The radiated signals are combined acoustically with the intention of improving the stereo sound in the listening area. However, Klayman specifically requires specialized wide dispersion tubes or multiple transducer elements to achieve the desired effect described. In addition, Klayman does not discuss excluding the primary frequency range of vocal energy from the output of any speaker to better organize the dialogue in the center speaker.

Other perimetric sound systems use complex signal processing in an attempt to improve the apparent separation between each of the left, center, right and perimeter channels. The most common system of this type currently in use is the DOLBY PRO-LOGIC decoding system. This system improves upon solutions to the basic problems of many passive decoding systems of the prior art, described above. Active electronic circuits 10 are used to decode audio signals encoded in matrix matrix, introduce time delays and achieve direction between channels through self-gain control circuits. However, improved performance requires a substantially higher expense because DOLBY PRO-LOGIC 15 requires a minimum of four separate amplification channels. In addition, by its very nature, active electronic signal processing systems, potentially^^ introduce a sonic artifact (a sound quality notnatural that can destroy the sense of realism) in your response. One such form of artifact in the DOLBY systemPRO-LOGIC results from active address circuits that vary the amount of adjacent channel signal that results from the signal. For example, when a dialogue is presentand it is desired that it be located to the center, the central channel signal is subtracted from the left and right channel signals to withdraw the dialogue energy from these channels. This variable subtraction is to dynamically vary the channel spacing to maintain the primary location in a particular direction. Listeners can often listen to the environment (which creates atmosphere in the audio-video presentation) . They enter and exit as dialogue enters and leaves the scene. The shrinking and new growth of the environment that accompanies the introduction and cessation of dialogue distracts the environment and causes a distinct disadvantage of this particular active electronic components approach to home theater sound reproduction. Another disadvantage to the DOLBY PRO-LOGIC is that it only works properly with coded program material. Uncoded material or material that has degraded in time is deformed, can confuse the logic circuits and cause extreme, strange spatial effects that occur when the decoder directs the location in an unintended way. Another major disadvantage of the active DOLBY PRO-LOGIC decoding system, includes its high cost to the consumer and its inherent complexity that makes it difficult for the consumer to install and use the system properly. More recently, there has been a return for trying to provide economical, less complex passive surround sound systems. An example of these systems are described in the U.S. Patent. No. 5,386,473, granted to Harrison. Harrison addresses the use• 5 of a transformer that passively decodes stereo line-level television output signals that require more amplification to produce the high-level signal needed to drive the speakers. The transformer receives left and right channel signalspower supply and provides front left, front right, rear left (L - R), right rear (R - L), center (L + R) and subwoofer channels. Harrison resorts to transforming low-level signals specifically to solve problemsperceived that result from the use of speakers connected to high-level amplifier outputs, to obtain a perimetric sound effect. However, Harrison cites disadvantages in operating a passive surround sound system satisfactorily with high-level signals. TheThe present invention is specifically directed to using high-level signals to provide surround sound, while alleviating the aforementioned problems regarding high-level system discussed by Harrison, such as the expenditure of high-energy components,balance and similar.

Other recent attempts at passive decoding include the QD-1 series II decoder manufactured byDynaco. The QD-1 decoder series II receives signals from the stereo amplifier. The decoder then produces• 5 four (or five) signals - two front speakers, two rear speakers and an optional center channel speaker. A second similar encoder is the HTS-1 decoder manufactured by Chase Technologies. Similar to QD-1, the Chase decoder receives signals from the amplifier and thengenerates signals for a pair of front speakers and a pair of^ fe rear speakers. The Chase decoder also produces a signal for an optional amplified center channel horn. These last two passive decoders havetwo primary disadvantages. First, the resistor network used to produce a signal (L + R) for the central channel dissipates energy, thus requiring a sufficiently large stereo amplifier or power receiver to overcome this loss of power.energy. It is preferable to provide a system in which all the loudspeakers of the system are displaced by a relatively low power amplifier, such as is found in a television or a portable boom box with portable resonance (boom box), whereno energy is wasted in networks of signal sum resistors. In one of the previous systems, the center channel horn must be energized in order to generate the desired function of maintaining dialogue location in the physical location of the central speaker. Second, because• 5 certain amount of signal (L + R) is fed to the rear sound speakers, artifact can occur in terms of dialogue emanating from the rear sound horn, thus disturbing the realism of the intended ambient effect. 10 In this way there remains a need for aEfe home theater surround sound speaker system that operates using relatively simple passive electronic components in order to limit its cost and thus provide a system that is attractive to themass market at a reasonable cost. Of particular importance in these systems is the convenience of presenting a consistent ambient sound field while maintaining the dialogue located in the video image for all positions in the auditorium and auditorium area.observation. The dialogue and visual images also preferably coincide in the video image and preferably do not move with each other in a particular speaker address. In addition, the audio designers have dedicatedSubstantial and particular attention is given to designing speaker systems that reproduce left and right channel audio signals from a stereo signal to create a sonic effect of three-dimensional perimetric sound. Nevertheless, audio designers have substantially • 5 ignored the monophonic sound market. Many consumers still have monophonic television equipment that outputs only a single monophonic channel, instead of the left and right channel components of a stereo signal. This currently relegates the consumer 10 who owns a monophonic television to have sound emanating only from the location of the television. In addition, • while the AM stereo continues to be discussed and can be used by a few limited stations, most AM broadcasts continue to be monophonic. Finally, many programs available on television, VCR, cable, satellite and other stereo audio / video signal supply systems have monophonic tracks. Some home / stereo theater audio / visual receivers apply signal processing techniques to the monophonic sound signal to produce simulated stereo or an enhanced spatial sound effect. This signal processing typically involves additional circuits and complexes of phase shift, filtering 25 and digital signal processing. The consumer of thisl? ^^^ lumu more? way must absorb the expense of acquiring this receiver, a perimetric sound decoder, or other electronic sound processing device and a convenient network of speakers to achieve a spatial effect• 5-dimensional or stereo simulated from a monophonic audio signal. Therefore, there is a need to provide a low-cost system for effectively reproducing monophonic audio signals in a form that creates a convincing three-dimensional sonic effect. 10 In addition to the obvious convenience of a home theater perimeter sound system that provides all the benefits described above, there is a more practical logistical problem in home theater systems. That is, according to the home theater systemscontinue to evolve, typically requiring an increasing number of additional components. These components often include active electronic exciters, numerous speaker connections, modules^^ Auxiliary control and interconnections of audio systemsseparated. This mess of components often confuses the average consumer during installation. Despite numerous attempts by manufacturers to make the installation more user-friendly and facilitate the installation procedure, many users experiencedifficulties in properly installing the system. The most recent attempts to facilitate the installation process have involved color coding of the speaker connections and the audio signal source in addition to labeling the connection plugs for the user to observe, and detailed installation instructions are provided. and complete. For many reasons, these measures have failed to provide the consumer with a sufficiently easy way to properly install the home theater sound system and many consumers are faced with the expense of a professional installation. In this way, it is additionally convenient to provide a perimeter home theater sound system that greatly facilitates the installation, so that the consumer can install in a relatively fast, easy and correct way and operate the system, thus improving attractive to the mass market. OBJECTIVES OF THE INVENTION The present invention achieves numerous objectives based on the novel application of a variety of acoustic design principles and through a novel combination of individual channel operation bandwidth and adjacent channel separation. An objective of the present invention is to create a realistic sound field to accompany video presentations that localizes dialogue on the video screen for all listeners through the presentation area which maintains a spacious and consistent three-dimensional field. A further objective of the present invention is to provide a low-cost sound reproduction system that produces authentic perimeter sound from a theater comparable or superior to that provided by matrix decoding systems with multi-channel electronic surround sound, active, complex and expensive. A further objective of the present invention is to passively uncouple dialogue playback and ambient audio signals to avoid the artifact of ambient instability associated with active, electronic signal processing and to ensure the presentation of a convincing integration of sonic images and visuals A further objective of the present invention is to provide spacious sound reproduction of conventional audio signal sources such as stereo signals encoded in two-channel stereo or matrix, without the need for electronic components for auxiliary matrix coding. A further objective of the present invention is to provide a system of speakers for sound reproduction having satellite speakers that simultaneously provide both localization indications and spacious sound reproduction of conventional audio signal sources. A further objective of the present invention is• 5 provide a speaker system for sound reproduction that produces a sonic effect of spatially enhanced surround sound for a monophonic audio signal. A further objective of the present invention is to provide a speaker system that is relativelysimple and direct for the average consumer in its installation and operation, including providing• Error-free connection by the consumer in a relatively short period of time. A further objective of the present invention isproviding a speaker system that connects easily and directly to a television set in stereo without the need for an additional audio-video receiver or amplifier. Still another object of the present invention isprovide a perimeter sound of the cinema at normal home listening levels, using the power amplifier with low wattage or wattage or equivalents available in commercial stereo TV sets. An additional objective of the present invention is to provide a speaker system having an extraordinarily small size and operating principle that incorporates tiny satellite speakers that can be placed non-protruding in the home environment without affecting sonic performance. COMPENDIUM OF THE INVENTION In accordance with the principles of the present invention, a home theater surround sound speaker system reproduces in a novel way the stereophonic audio portion of an audio / video presentation such that the dialogue is located in the video image and the viewer is immersed in a field of sound that is perceived as authentic in relation to the visual image. In a first preferred embodiment of the present invention, the passive non-energized speaker system includes a front speaker, a left speaker, a right speaker and a rear speaker, each speaker receives an electrical power signal and provides an acoustic output in accordance with an electrical power signal. The front speaker is located in proximity with the video image and provides an acoustic output according to the leftmost right sum (L + R) of the left and right channels of the stereo signal, so that the dialogue is located in and matches the video image. The left and right speakers may be coplanar with the front speaker but preferably located between the viewer and the front speaker, and left and right sides of the observation area, respectively. The speakers provide acoustic output• 5 according to the respective left and right stereo channels. The rear speaker is located at the back of the observation area and provides acoustic output according to a difference left less right (L - R) or right less left (R - L) betweenstereophonic channel signals. The difference signalThis faith substantially filters out the dialogue and provides the audio information of surround sound and environment. The power supply of left and right channel electrical signals to the respective speakersleft and right, are limited in band to substantially remove all frequency components below a predetermined threshold frequency. The band limitation ensures that the dialogue is located in the front speaker, since the filtering is substantiallyremoves signal energy in the speech signal range from the left and right channel signals that are reproduced acoustically. In a second preferred embodiment, the non-energized, passive speaker system includes a front speaker,a left speaker, a right speaker and a rear speaker, each speaker receives an electrical power signal and provides an acoustic output according to the power supply signal. The front speaker is located in proximity to the video image and provides• 5 an acoustic output according to a leftmost right sum (L + R) of the left and right channels of the stereo signal, such that the dialogue is located on and matches the video image. The left speaker can be coplanar with the front speaker, butpreference is located between the viewer and the speaker4fc frontal, and to the left side of the observation area. The left speaker provides acoustic output according to an electrical difference feed signal (L - ßR) for example, where ß is a gain factor that variesbetween 0 and the unit or can be a fixed value between 0 and the unit. Similarly, the right speaker is preferably located between the viewer and the front speaker, and to the right side of the observation area. The right speaker^^ provides acoustic output according to a signal fromdifference (R - ßL) for example, where is a gain factor that varies between 0 and the unit or can be a fixed value between 0 and the unit. The rear speaker is located at the rear of the observation area and provides acoustic output 'according to at least one of thedifference left less right (L - R) or right less left (R - L) between stereophonic channel signals. Using the difference signal substantially removes the dialogue portion of the audio signal, thus leaving the ambient sounds in the difference signals.

• In this second preferred embodiment, the difference signals that are fed to the respective left and right speakers can also be bandlimited optionally to remove substantially all frequency components below a frequencypredetermined threshold. The band limitation for the difference signals substantially removes the low frequency components in the difference signals, so that the difference signal can be reproduced using the compact speakers excessivelysmall. In a further preferred embodiment of the present invention, which is a novel variant of the first and second embodiments, the speaker system is not^^ energized passive, includes a front speaker, a hornleft, one right speaker and one rear speaker, each speaker receives an electrical power signal and provides an acoustic output according to the power supply signal. The front speaker is located in proximity to the video image and provides an outputacoustic according to a left plus right sum (L + R) of the left and right channels of the stereophonic signal, so that the dialogue is located in and matches the video image. The left and right speakers can be coplanar with the front speaker, but* 5 are preferably located between the viewer and the front speaker, and the left and right sides of the observation area, respectively. Each of the speakers provides two acoustic outputs according to the respective left and right stereo channels andan electrical difference (L-R) or (R-L) power supply signal. The left speaker provides acoustic output• according to the left channel signal and the electrical difference signal (L - R). Similarly, the right speaker provides acoustic output according to the signalof the right channel and the electrical difference signal (R - L). The rear speaker is located at the rear of the observation area and provides acoustic output according to a difference left less right (L - R) or right less left (R - L) between channel signalsstereophonic. The difference signal substantially separates by filtering dialogue and provides audio information of surround and surround sound. The power supply of left and right channel electrical signals to the respective left and right speakers is band-limitedto remove substantially all frequency components below a predetermined threshold frequency. Band limiting of the respective signals fed to the left and right satellite speakers provides a compromise between the sonic amplitude and location indications that are output from the left and right speakers. In a third preferred embodiment, the powered speaker system includes a front speaker, a left speaker, a right speaker and a rear speaker, each speaker receives an electrical power signal and provides an acoustic output in accordance with the power supply signal . Active electronic components pre-process and amplify the left and right channels of the stereophonic signal to provide a left-most right-sum signal (L + R) and a difference signal, (L-R), for example. The resulting sum and difference signals drive the individual horns of the speaker system. The front speaker is located in proximity to the video image and provides an acoustic output according to the sum signal, such that the dialogue is located on and matches the video image. The left speaker is located on the left side of the observation area and provides acoustic output according to the difference signal, (L - R) for example. The right speaker is located on the right side^^^^ of the observation area and provides acoustic output according to the difference signal, (R - L) for example. The rear speaker is located at the rear of the observation area and provides acoustic output from• 5 according to a difference signal. In this third preferred embodiment, the difference signal can be reversed by inverting the polarity applied to a particular speaker. Also, in this third mode, the difference signals fed to the left and right speakersThe respective ones can optionally be limited in band to remove substantially all the components of• frequency below a predetermined threshold and allow reproduction of the difference signal using compact, excessively small speakers. In a fourth preferred embodiment, the system includes a front speaker, a left speaker, a right speaker and a rear speaker, each speaker receives an electrical power signal and provides a^^ monophonic acoustic output according to a signal frommonophonic power supply. The front speaker is located in proximity to the video image and provides an acoustic output in accordance with the monophonic signal. The left speaker can be coplanar with the front speaker, but is located between the viewer and the front speaker andto the left of the observation area. The left speaker provides monophonic acoustic output according to a monophonic power signal. Similarly, the right speaker is preferably located between the viewer and the front speaker and on the right side• 5 of the observation area. The right speaker provides a monophonic acoustic output according to a monophonic power supply signal. The rear speaker is located at the rear of the observation area and provides a monophonic acoustic output according to a monophonic power signal. Using the monophonic signal f allows users who have only monophonic audio output sources to obtain an enhanced spatial sonic image or a sonic sound effect based on the monophonic signal. The monophonic signal feed 15 to the respective left and right horns is bandlimited, as described herein, to remove substantially all frequency components below the predetermined threshold frequency. The• Band limitation of the monophonic signal substantially removes the low frequency components in the monophonic signal, so that the signal can be reproduced using compact, relatively small satellite speakers. The band limitation also restricts reproduction of the primary vocal energy to the central speaker.

The present invention may also include a power amplifier for receiving left and right power signals and amplifying the left and right power signals to output to the respective speakers. An energized version that has integral amplifiers allows the system designer to generate amplified output signals tailored to the specific speakers selected by the system design. This integrated design approach facilitates the optimization of the acoustic output of the system. The present invention can furthermore allow and an additional basis for reproducing low frequency components of stereophonic signals. The bass speaker only needs to be located generally in the observation area and provides an acoustic output according to the low frequency components of the sum signal (R + L). The present invention also includes an interconnection module to facilitate installation and operation by the user. The interconnect module includes power and output plugs that have a predetermined number of terminals. The predetermined number of terminals indicates which signals are fed or output by the plugs. For example, a three-prong outlet plug outputs a left, right, and common electric signal, respectively. This configuration of the input and output plugs ensures proper installation of the system because the user can only install the speaker system in a particular configuration. The design of the speaker system may include the interconnection module as an autonomous additional component of the system or may incorporate the interconnection module circuit with one of the existing components, such as the base horn or the front speaker. The present invention also includes a wireless implementation. In the implementation• wireless, an electrical audio signal connection provides an audio signal to the interconnect module from the audio signal source, theThe interconnection includes active electronic components to produce both difference and sum signals. A radio transmitter receives the difference signal and transmits the signal. The left, right and rear speakers include g ^ each a radio receiver tuned to the frequency of thetransmitter. The receivers then provide an amplified electrical signal suitable for production of an acoustic output by the associated speaker. From the subsequent detailed description taken in conjunction with the accompanying drawings and claimsAttachments will be apparent to other objects and advantages of the present invention for those skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS £ Figure 1 is a block diagram of the home theater surround sound speaker system 5, arranged in accordance with the principles of the present invention; Figure 2 is an expanded block diagram of a first preferred embodiment of the home theater surround sound speaker system of Figure 1; Figure 3a is an expanded block diagram of a second embodiment of the home theater surround sound speaker system of Figure 1 where different signals send output to the left and right satellite horns; Figure 3b is an expanded block diagram of a variation of a second preferred embodiment of the home theater surround sound speaker system of Figure 1, wherein the signal subtracted to produce the difference signals is attenuated before subtraction; Figure 3c is an expanded block diagram of an additional embodiment that is a variant of the first and second modes of the home theater surround sound speaker system, where the left and right satellite horns provide both an output- * - - - - acoustic left as right respectively and an acoustic output (L - R) and (R - L), respectively; Figure 3d is a partial schematic diagram of an exemplary right channel satellite horn for the • 5 Figure 3c: Figures 4a and 4b are circuit diagrams for the first and second order high pass filters respectively, to limit the power signal to the left and right satellite horns in bandwidth; and 5b are circuit diagrams for applying a rightmost left-sum signal (L + R) to the central speaker, using a simple transducer of a dual transducer configuration respectively: Figures 6a and 6b are circuit diagrams 15 for applying a left minus right difference signal (L - R) to the rear loudspeaker of the home theater surround sound speaker system, using dual and single speech voice coil configurations, - ^ respectively; Figure 7 is an expanded block diagram of a third preferred embodiment of the home theater surround sound speaker system where the left and right channel addition and difference signals are actively generated before sending the two outputs. horns;> i > -k ^ U_t_________i Figure 8 is an expanded block diagram of a fourth preferred embodiment of the home theater surround sound speaker system, wherein a monophonic signal is output to each of the speakers;• Figure 9 is a wiring diagram for an interconnect module for the home theater surround sound speaker system used to facilitate installation and error-free operation of the system; 10 Figure 10 is a block diagram of a^ - alternating configuration for the home theater surround sound speaker system illustrated in Figure 1; Figure 11 is a perspective view of an integral subwoofer base unit and interconnect module; Figure 12 is a wiring diagram of the home theater surround sound speaker system, bass subwoofer base unit and connection modules^^ integral of Figure 11, used to facilitateinstallation and operation free of system error; and Figure 13 is a block diagram of a wireless implementation of the home theater surround sound speaker system. DETAILED DESCRIPTION OF THE PREFERRED MODALITIES The following description of preferred embodiments is simply exemplary in nature and is not intended to limit the invention or its application or uses. In the specification, it should also be noted that elements that have similar structures or functions are• 5 will refer using similar reference numbers. The modalities described here provide several improvements over the prior art and will be discussed briefly at the beginning. First, this invention involves the spatial distribution of several speakerswith respect to the listening room in order to add to the perception of amplitude of the audience. The distribution• Space includes left and right side speakers, a rear speaker, a front (or center) speaker and a subwoofer. Second, this inventioninvolves locating sound radiation patterns to a front or center speaker, to create an illusion to the listener that certain sounds emanate from that speaker. This invention also involves the reproduction of sounds^ individuals to create ambient surround sound tothrough the room. This preference sound emanates from speakers other than the front or center speakers. Third, this invention involves frequency band management to eliminate particular acoustic frequencies that are produced by the satellite speakersleft and right. The frequency for band limitation is chosen according to the desire to eliminate the vocal power output of the satellite speakers. Fourth, this invention involves an atypical super position f- ^ of the frequency ranges of the horn components.

In this way, each of the front, rear and side horns each have a range of superposed, rather broad, frequencies. Fifth, this invention passively outputs acoustic signals from the left channel, the right channel, the left channel and the right channel, andleft channel less right, using several different means of passively generating the signals. Figure 1 illustrates a diagramatic view of the home theater surround sound system (the perimetric sound system) 10, arranged in accordancewith the principles of the present invention. The perimetric sound system 10 includes a source of an amplified stereo signal, preferably illustrated in Figure 1 as a television set 12. The stereo audio source can be any of a number of audio sources.audio signal. It should be noted in this manner that the source of a stereo audio signal is represented here as the television 12, but the audio signal source can also be a stereo receiver, a car stereo, or a compact disc type player portable, aboom-box type stereo with portable boom box or any other source of a stereo signal. The television 12 outputs an amplified audio signal to interconnect the module 14 through• 5 a multi-conductor cable 16. The multi-conductor cable 16 typically includes two conductor pairs to drive the left and right channels of the stereo signal that is output from the television 12 to interconnect to the module 14. The moduleof interconnection 14 receives the audio signals from television 12 and assembles the left channel signals and• Right components for selective distribution to loudspeakers of particular components of the surround sound system 10. 15 The component loudspeakers typically include a subwoofer for bass 18 that receives left and right signals from the internal range, but only reproduces the low frequency components of the audio signal. He^ _ interconnection module 14 also sends out an9 20 audio signal to the front center speaker 20. The front center speaker 20 receives both the left and right component signals from the stereo signal and reproduces the sum signal (L + R). Preferably, the front central speaker 30 is located in proximity to thetelevision 12 and projects the acoustic output of the sum signal (L + R) to the listener 28. The interconnection module 14 also outputs the left channel signal to the left-hand satellite horn 22 and the right channel signal to the right satellite horn 5. The left satellite horn 22 and the right satellite horn 24 can be relatively small speakers and only need to reproduce high frequency and / or midrange signals. Left and right satellite horns, preferably oriented in such a way that the primary axis of radiation of the points of the speaker signals ß? up on a vertical axis; however, other orientations of the satellite speakers can also provide satisfactory performance. The interconnect module 14 also outputs an audio signal 15 to the rear ambience horn 26. The rear ambience horn 26 typically receives an audio signal in the form of a left channel signal minus the right channel (L-R). ) or right channel minus left channel (R - L). As will be apparent from this detailed description, various embodiments of the invention described herein allow the interconnect module 14 to generate a variety of signals that are output to the left satellite horn 22, the right satellite horn 24 and / or the rear environment horn 26. It should be noted at the beginning that the term horn refers to a systemj ^^^^ ^ s? ^^ ygj ^ gto to convert electrical power signals to acoustic output signals where the system can include one or more of crossover networks and / or transducers. The components described in Figure 1,• 5 are typically arranged to optimize the perimetric sound effect to enhance the auditory experience of the viewer 28. The viewer 28 typically faces the television 12 having a front center speaker 20 disposed in proximity to the television 12, such asthat the central speaker 20 and the television 12 radiate their respective audio and video outputs at the address• general viewer 28. The left satellite horn 22 is typically disposed on the left side of the viewer 28, while the right satellite horn 24 is arranged at theOn the right side of the viewer 28, both satellite horns typically are nominally located in the middle between the viewer 28 and the television 12. The rear ambience horn 26, which contributes to creating a spacious audio effect, is typically located behind the viewer. .

The ambient horn 26 is illustrated as a single horn, but multiple rear horns 26 can be included in the system. Figure 2 illustrates an expanded block diagram of a preferred embodiment of the presentinvention. The expanded block diagrams described herein generally include a partial circuit and wiring diagrams and will be referred to in an interchangeable manner according to this specification as a block, circuit or wiring diagrams. The home theater surround sound system 111 (perimeter sound system) includes a left side satellite horn 102 (satellite or left side horn, (right side satellite horn 104), (satellite horn or right side speaker) ), central speaker 106, bovine 10 perimeter or rear 108 and subwoofer speaker for bass 10. The left channel amplifier 102 outputs an amplified left channel signal, which is fed to the positive terminal of voice coil 114a of the central speaker 106. The negative terminal of the voice coil 114a of the central speaker 106 connects to the negative terminal of the left channel amplifier 112. Similarly, the right channel amplifier 116 outputs a right channel signal amplified that is fed to the positive terminal of the voice coil 114b of the central speaker 106. The negative terminal of the voice coil 114a of the central speaker 106, con cta with the negative terminal of the right channel amplifier 116. The left and right channel signals are thus connected in phase to the two voice coils 114a and 114b of the central speaker 106, so that the output of the• - ^ --- y.-rv - t, itin. i ?? M __________ M__M__i ____. ^^ ..... ^ Éaaa ^ a * _________ ^ ___________ ^ __ ^. ^ ttllttÉ central speaker 106 is the sum of the left and right channel signals (referred to here as L + R). The positive terminal of the left channel amplifier 112 also outputs a channel signal• left amplified to the positive terminal of the left-side speaker 112 through a filter 118. The negative terminal of the left-channel amplifier 102 is connected to the negative terminal of the left-side speaker 102. Similarly, the positive terminal of theThe right channel amplifier 116 also outputs an amplified right channel signal to the positive terminal of the right-side speaker 104 through a filter 120. The negative terminal of the right channel amplifier 116 connects to the negative terminal of the right channel amplifier 116. the Hornon the right side 104. In this manner, in the embodiment of Figure 2, the amplified left and right channel signals are output to the respective left and right side speakers. _________ The left side speaker 102 and the speakerright-hand side 104 are preferably band-limited to reproduce only higher frequencies, as shown using the left high-pass filter 118 and the right-high-pass filter 120. The use of high-pass filters 118 and 120 with the loudspeaker left and right side, respectively, 102 and 104, limits the acoustic output of theDailifaM ErmaMißa left and right side horns 102 and 104 at high frequencies. As will be described in more detail with respect to Figures 4a and 4b, this band limitation of the satellite horns 102 and 104 excludes the range of• 5 primary frequency of vocal energy. The listener, in this way, perceives a dialogue sound that comes only from the front speaker 20 located in proximity to the video image. Examples of these high-pass filters will be described in greater detail with respect to Figures 4aand 4b. Surround sound system 100 also includes a rear speaker 108. Feedings to rear speaker 108 provide a resultant minus left difference signal (L-R). To effectIn this difference signal, the positive terminal of the left channel amplifier 112 outputs the amplified left channel signal to the positive terminal of the rear speaker 108, and the positive terminal of the right amplifier 116 outputs the signal of the left amplifier. channelright amplified to the negative terminal of the rear speaker 108. The above-described connections to the rear speaker 108 provide the desired difference signal (L-R). The rear speaker 108 also includes a potentiometer 109. The potentiometer 109 allows adjustmentof the rear horn acoustic output with respect to the output of the other speakers in the system. This output is typically adjusted according to the proximity of the rear speaker to the listener. It will be recognized by a person with skill in the technique that a polarity connection# 5 inverted to the rear speaker 108 provides a difference signal (R-L) instead of a difference signal (L-R). The polarity of the difference signal radiated by the rear speaker does not significantly affect the performance of the surround sound system 100 and anyalternative can be selected. The perimetric sound system 100 also• includes a subwoofer for bass 110. The positive terminal of the left channel amplifier 112 outputs an amplified channel 100 signal to the terminalpositive subwoofer speaker for left bass122. The negative terminal of the left channel amplifier 102 is connected to the negative terminal of the left subwoofer speaker 122.

^^ Similarly, the positive signal of the channel amplifierright 116 outputs the amplified right channel speaker to the positive terminal of the right subwoofer speaker 124. The negative terminal of the right channel amplifier 116 connects to the negative terminal of the subwoofer speaker right 124.

In this manner, the mode of Figure 2, the left side signal controls the left subwoofer horn 122 and the right channel signal controls the right subwoofer horn 124, respectively. The resulting output from the speakers• 5 subwoofer for left and right bass, this way it adds acoustically. It will be understood that a person skilled in the art that the center channel horn 108 can operate alternatively over a full range of frequencies including the base range, in this wayeliminating the subwoofer for bass. A- In an alternate mode of the preferred embodiment described above, the left and right amplifiers 112 and 116 can be integrated into the system. For example, left and right channel amplifiers112 and 116, while in general it is considered through this specification that are output amplifiers that are commonly found and include the aforementioned audio signal sources, they can be amplifiers________ specifically select that form a portion of the systemsurround sound 100. Amplifiers 112 and 116 in this alternate mode will receive low level power signals from the audio signal source. The amplifiers 112 and 116 will further amplify the power signal for output to the system's speakers.surround sound. To effect this configuration, the output amplifiers 112 and 116 can be incorporated in the interconnection module 14 (as illustrated in Figure 1). The interconnect module 14 will preferably be energized independently to displace the amplifiers 112 and 116. A particular advantage of this alternate configuration is that the output amplifiers 112 and 116 can be designed to be specifically integrated with the electrodynamic characteristics of the amplifiers. horns. A preferred embodiment of the perimetric sound system 100 includes a central speaker 106 that • comprises a sealed enclosure of an approximate housing of 819.5 cm3 (50 in3), which receives an 8-ohm dual voice ohmic electrodynamic transducer with diameter 15 of 7.62 cm (3"), commercially available A pair of microfarad capacitors 100 connected in series with the positive output of the respective left and right channel signals perform a crossover function. The central horn 106 has a width of operating band on W 20 approximately 150 Hz. The rear speaker 108 uses a similar configuration but employs a single voice coil, instead of a dual voice coil transducer.The rear horn 108 includes a sealed enclosure of approximately 819.5 cm3 (50 in3), and houses an 8 ohm spindle voice coil electrodynamic transducer 25 withLi ln, mi _ ^^ _- ^^ J, j - i -. ^ Bja | tM¡ai || commercially available 7.62 cm (3") diameter Potentiometer 109 is a 15-watt, 8-ohm L-pad, or a 3-watt, 25-ohm wound wire potentiometer, an 85-microfarad capacitor connected in series with the • 5 the positive first power of the voice coil performs a crossover function The nominal frequency band of the rear horn 108 is 150 Hz to 8 KHz. The rear horn 108 reproduces a difference signal (L-R) as it is described with respect to Figure 2. The 10 side horns 102 and 104 each comprise a sealed enclosure 4 of approximately 32.78 cm3 (2 in3) and houses a plastic cone treble loudspeaker with a diameter of 3.81 cm (1.5") 4 ohm impedance commercially available. A pair of 4.7 micro farads 15 capacitors connected in series with the positive side speaker feeds 102 and 104 provides high pass filtering for left high pass filter 118 and right high pass filter 120. High pass filters 118 and 120 ^^ provide a nominal frequency band of 9 20 about 4 KHz to 15 KHz output from side horns 102 and 104. The subwoofer 110 is a conventional dual volume enclosure design comprising a nominal sealed volume in 9,506.2 cm3 (580 in3) and a nominal gate volume of 7,375.5 cm3 (450 25 in3) that operate in conjunction with a pair of transducerslMfa * _i_ ^ atl¿ ^^ rf¡H 4 ohm voice coil electrodynamics with a diameter of 13.34 cm (5.25"). A pair of 0.8 milli-Henry inductors in series with positive power to each of the transducers performs a crossover function The bass subwoofer base unit 110 operates nominally on the frequency bar from 50 Hz to 200 Hz. It should be noted that each of the above-described speakers, the crossover network is integrated into the enclosure Furthermore, it will be noted that the band-limiting filters 118 and 120 are integrally included in the horns 102 and 104, respectively, In this way, the band-limiting device and the associated satellite horn form an integrated unit. allows the added benefit that the interconnect module 14 in Figure 1 can simply be constituted by appropriately wired power and outlet plugs Figure 3a illustrates a second preferred embodiment of the present invention The home theater surround sound system (perimeter sound system) 200 of Figure 3a employs components similar to those employed in the surround sound system 100 of Figure 2, and similar components will be referred to using reference numbers. starting with 200 instead of 100. The perimeter sound system 200 of Figure 3a is as described in Figure 2 except• "* '* *' <« ^ «- ^^^ because the left-side speaker 202 and the right-side speaker 204 are configured to reproduce difference (L-R) and (R-L) signals, respectively The positive terminal of the left channel amplifier 212 outputs an amplified left channel signal to the positive terminal of the left side speaker 202 through a filter 218. The positive terminal of the right channel amplifier 216 outputs a signal amplified right channel, connected to the terminalThe positive terminal of the right channel amplifier 216 outputs an amplified right channel signal to the positive terminal of the right side speaker 204 by a filter 220. The positive terminal of the left-side speaker 202. Similarly, the positive terminal of the right-hand amplifier 216 channel amplifierleft 202 outputs an amplified left channel signal, which is connected to the negative terminal on the right side 204. These connections provide a difference signal power (L-R) to the left-side speaker 202 and a power supply of difference signal (R - L) to theright side speaker 204. As described with respect to Figure 1, the left high pass filter 218 and the right high pass filter 220 filter out low frequency components of the power signals applied to theleft side speaker 202 and the right side speaker^ j¡jg¡ 204, respectively. In applications where the satellite horns receive difference signals as feeds, the high pass filtering as described in Figure 2, of the difference signals becomes optional. However, there are two additional benefits to high pass filtering of difference signals (L - R). First, the physical size of the side speakers may remain small. Second, mismatches in the gains of left and right channel signals may cause the dialogue to leak to the channel difference. Bandwidth of the difference signal helps in accelerating that the localization in the dialogue remains in the center speaker site, even though the signals in the left and right channels are not exactly the same and the dialogue leaks in the difference signal , when filtering out of this signal difference in the primary voice frequency range. In an alternate configuration of the second preferred embodiment, reversing the polarity of the difference signal results in a difference signal (L-R) applied to the right-hand horn and a difference signal (R-L) applied to the left-side speaker 202. Still in another alternate mode, a difference signal (L-R) can be applied to both side horns 202 and 204, or a difference signal (R-L)^ á m m puede E can be applied to both side horns 202 and 204. The particular polarity of the difference signal applied to the side speakers does not materially affect the performance of the system when the difference signals are limited in • 5 band because the side horns operate nominally on 1 KHz where the acoustic difference is inaudible. In addition, because the wavelengths of difference signals in this frequency range are relatively short, small changes in the relative placement of the side horns 202 and 204 will have more than? an effect on the way in which the signals are combined from a listening position to what will be the relative polarity of the signals applied to the side speakers. A particular advantage of directing the left side speaker 202 and the right side speaker 204 with the difference signals (either (L-R) or (R-L) is that the difference signal removes sound components equally recorded in the left and right channels, effectively decoupling dialogue playback and ambient surround sound, considering a system where the left and right channel signals are output to the respective left and right satellite speakers, residual vocal energy harmonics they can still receive from the left and right signals up to 25 frequencies, such as harmonic overtones, which can be heard..., - * - > . ? ..? r. ,. r__. ^^ j ^^ ^^ J ^ i ^ as whistling sounds. When these hissing sounds are reproduced by satellite speakers, the satellite speakers provide a directional indication that may result in an unnatural pause in the dialogue and smear or soil the sonic image. The difference signal, however eliminate these problems by removing all traces of dialogue energy from the ambient surround sound. An additional benefit can be had by limiting in band of the signal of difference that containssubstantially only perimeter sound informationf environment The band feed of the difference signal allows the use of a much smaller satellite horn because the satellite horn only needs to reproduce high frequency acoustic output. Thisway, the combination of band limitation and the use of difference signals succeeds in decoupling dialogue playback and ambient sounds, which ensure the location of the dialogue in the video image,^ _ While maintaining an ambient sound fieldconsequent. This decoupling introduces a fundamental difference between the passive system of the present invention and the active perimetric sound decoding systems. The passive system described does not introduce any sonic artifact when the dialogue entersand passes within a field of ambient sound recorded in the sound track. In this way, a consistent ambient sound field results while the dialogue remains localized on the video screen. The connections for the center speaker, subwoofer for bass, 5 and rear speaker shown in Figure 3a are the same as described with respect to Figure 2. The left channel amplifier 212 outputs a left channel signal amplifier that is fed to the positive terminal of the voice coil 214a of the center speaker 10. 236. The relative terminal of the voice coil 214a of the center speaker 206 connects to the negative terminal • of the left channel amplifier 212. Similarly, the right channel amplifier 216 outputs an amplified right channel signal which is fed to the positive terminal 15 of the voice coil 214b of the center speaker 206. The negative terminal of the voice coil 214b of the center speaker 206 connects with the negative terminal of the right channel amplifier 216. The left and right channel signals ^^ in this manner are connected in phase with the two voice coils 214a and 214b d e the central speaker 206, such that the output from the central speaker 206 are the left and right summing signals. Again with reference to Figures 2 (and 3), the left side speaker 102a (202) and the right side speaker 104 (204) receive the output of amplified signals• * - * • - > - ^ - «* -. ~» - «- ........ .... ^ R ... .,. < * r ^ .i. Í Í ^ ?. amtuiAßt * »».by the left and right channel amplifiers 112(212) and 116 (216), respectively. However, the operating bandwidth of side horns 102 (202) and 104(204) is restricted. The bandwidth of the speakersside panels 102 (202) and 104 (204) of the present invention are limited to a range of frequencies substantially over the primary frequency range of the voice signals or dialogue output by the center speaker 106 (206). More particularly, the primary energy in the signals ofspeech is contained in the frequency range of approximately 150 Hz to 1 KHz. Side speakers 102• (202), 104 (204) are limited in bandwidth by high-pass filters 118 (218) and 120 (220), respectively to operate in the frequency range at least overapproximately 1 KHz. Figure 3b illustrates a variation of the second preferred embodiment of the present invention. The home theater surround sound horn system (perimeter sound horn system) 200 'of Figure 3b ^^ 20 employs components similar to those employed in the surround sound systems 100 and 200 of Figures 2 and 3a, and similar components of Figures 2 and 3a will be referred to using identical reference numbers. The perimeter sound system 200 'of Figure 3b is likeis described in Figure 3a except that the left side speaker 202 and the right side speaker 204 are configured to produce difference signals (L - ßR) and (R - ßL), respectively. As in Figure 3a, the positive terminal of the left channel amplifier 212 outputs an amplified left channel signal to the positive terminal of the left side speaker 202 by a filter 218. The positive terminal of the right channel amplifier 216 sends of output an amplified right channel signal which is connected to the negative terminal of the left-side speaker 202 by an attenuator 270. Similarly, the positive terminal of the right channel amplifier 216 outputs an amplified right channel signal to a terminal positive of the right-side speaker 204 by a filter 220. The positive terminal of the left-channel amplifier 212 is outputted by an amplified left-channel signal that is connected to the negative terminal of the right-side speaker 204 by the attenuator 272. The attenuators 270 and 272 reduce the subtracted signal before feeding to the negative terminals of the respective side horns. 202 and 204. This results in an output (L-ßR) of the left-side speaker 202 and (R-ßL) of the right-side speaker 204, where ß is defined as the gain of the attenuators 270 and 272 , respectively. The gain ß of the attenuators 270 and 272 preferably has a value between 0 and unity. In addition, as will be understood by a person skilled in the art, the ß gain of the attenuators 270 and 272 can be fixed or can be variable, according to the• 5 particular design specifications. In addition, each attenuator 270 and 272 can optionally provide a different gain such that the attenuator 270 provides a gain ßj of the attenuator 272 providing a gain ß2. A person with skill in thespecialty will easily recognize many different implementations of attenuator 270 and 272, to provide• a profit ß. For example, amplifiers 270 and 272 can be implemented as resistors or potentiometers, in a relatively simple implementation. In aIn a more complex implementation, the attenuators 270 and 272 can be implemented in any of a number of amplifier configurations known to those skilled in the art. ___-_. Figure 3c illustrates a novel variant offirst and second preferred embodiments of the present invention. The home theater surround sound system (perimeter sound system) 500 of Figure 3c employs components similar to those used in the surround sound systems 100, 200 and300 of Figures 2, 3a and 3b. Similar components will refer to using similar reference numbers starting with 500. The perimetric sound system of Figure 3c operate substantially as described in Figures 3a and 3b. A particularly feature• The novelty of this additional embodiment is that the left-side speaker 502 and the right-hand speaker 504 are configured to produce both a pure left or right acoustic signal, respectively and an acoustic output (L-R) and (R-L) ). In particular, the left channel speaker 10 502 outputs an acoustic left channel signal limited in band and an acoustic difference signal• Limited in band (L - R). Similarly, the right channel horn 504 outputs a band-limited right channel acoustic signal and a band-limited acoustic difference (R-L) signal. As in Figures 3a and 3b, the positive terminal of the left channel amplifier 512 outputs an amplified left channel signal which is fed to the left channel filters 518 and 580 which operates generally as described above with respect to Figures 2, 3a and 3b. In this embodiment, the left-side speaker 502 includes a pair of acoustic output sources 572 and 574, which can be implemented using transducers. Filters 518 and 580 send outrespective filtered left channel signals. The signal- < * - * * * filtered left channel that is output from the filter 518 is fed to the positive terminal of the transducer 572. The negative terminal of the transducer 572 is connected to ground or common. The transducer 572 of this• 5 way provides an acoustic output according to the filtered left channel signal. The filtered left channel signal leaving the filter 560 is fed to the positive terminal of the transducer 574. The negative terminal of the transducer 574 is connected to the channel signalright per output through the amplifier 516. The transducer 574 in this way provides acoustic output• according to a signal of limited difference in band (L - R). The left-side speaker 502 in this way provides an acoustic output in combination, whichcorresponds to a filtered left channel signal and a filtered difference signal. Similarly, the right channel amplifier 516 outputs an amplified right channel signal which is fed to the filters 520 and 582, which also operates• generally as described above with respect to Figures 2, 3a and 3b. The right-side speaker 502 includes a pair of acoustic output sources 576 and 578, which can be implemented using transducers. Filters 520 and 582 send outputrespective filtered right channel signals. The signal- r.ti.r.llÉ. - ... n, t 'i? ^ «ait > .--- i ^ ilaiÉ > M__ laai_i_______M_ > ________ ^^ filtered right channel output of filter 520 is fed to the positive terminal of transducer 576. Negative terminal of transducer 576 is connected to common or ground. Transducer 576 in this manner provides acoustic output 5 according to the filtered right channel signal. The filtered right channel signal output from filter 582 is fed to the positive terminal of transducer 578. The negative terminal of transducer 578 is connected to the right channel signal exiting amplifier 512. Thetransducer 578 in this manner provides acoustic output according to a signal of limited difference in band (L• - R). The right-side speaker 504 in this manner provides an acoustic output in combination corresponding to a filtered left channel signal and afiltered difference signal. The acoustic output provided by the left side speaker of the dual transducer 502 and the right side speaker 504 provide advantages of^ aa, performance versus the modalities described above.

In particular, the left side speaker 502 and the right side speaker 504 provide a greater range of product functionality. The band-bound left and right acoustic signals that are output from the transducers 572 and 576, respectively, providelocalization indications that help in defining a traditional left and right stereo image. Left and right signals limited in band will achieve this better than the respective difference signals. The difference (L-R) and (R-L) signals output from transducers 574 and 578, respectively, allow the left-side horn 502 and the right-hand horn 504 respectively to provide a sonic amplitude, which contributes to the environment provided by the surround sound system 500. The configuration of Figure 3c is equally applicable to conventional sound systems, such as for use in perimetric music and theater sound applications and multimedia surround sound applications, such as as to use in computer applications. In conventional audio listening applications, audio output sources, such as speakers, are typically placed remote from the listener, and ideally located in proximity to the center of the room. This usually provides enough space for both location indication and ambient audio output to merge into a realistic integrated sound field. On the other hand in multimedia applications, the user is typically in close proximity to a computer video monitor, and the speakers are usually placed in immediate proximity to the display. This^^^ ¡^^ É ^? ^^^ a ^ allows limited space for both location indication and ambient audio output to merge into a realistic integrated sound field. Although the general configuration of Figure 3c equally applies to both multimedia perimetric and conventional sound applications, each system requires a slightly different balance in order to provide optimum results. This balance can be achieved through proper selection of the bandpass capabilities of filters 10 518, 520, 570 and 572, suitable selection of transducers 572, 574, 576 and 578 and adjustment of signal levels. For use in conventional applications, each filter 518, 520, 570 and 572 can be implemented using a capacitor. In a preferred embodiment, the capacitor may be a capacitor of 4.5 micro farads. Each transducer 572, 574, 576 and 578 can be a 3.81 cm (1.5") transducer. This configuration provides a nominal frequency band of approximately 4 KHz at 15 KHz that leaves each transducer of the side horns 502 and 20 504. In multimedia applications, it is convenient to maintain a similar nominal frequency band for output of transducers 574 and 578 that output the respective difference signals.To achieve this, filters 580 and 582 are implemented using a capacitor of 4.7 microfarads , and transducers 574 and 578^ ¡, - - -,, i 1, - -i «m» ^ Mia ^ | i¿ ^ jM ^ ¡^^^^^^^^^^^^ M ^ aM ^^^ É ^ jH ^ &i are preferably 3.81 cm (1.5") transducers. In multimedia applications, it is also convenient to provide additional directionality from transducers 572 and 576, which send out signals• 5 acoustic left and right respectively. To provide this increased directionality, filters 518 and 520 are implemented using a capacitor of 100 micro farads and transducers 572 and 576 preferably are 6.35 cm (2.5") drivers.desired acoustic for multimedia applications. In addition, a person skilled in the art will recognize that if a monophonic signal is applied to the left L and right R feeds, the configuration of Figure 3c will provide an improved acoustic effect to systemsconventional. Figure 3d is an exemplary assembly for the right-side speaker 504 of Figure 3c. As described with respect to Figure 3c, the right-side speaker 504 includes a pair of transducers 576 and 578. The• Transducer 576 provides an acoustic output according to a filtered right channel signal. A capacitor 520 operates as a filter to supply the right channel signal output in band. Similarly, transducer 578 provides an acoustic output in accordance with a signal (R-. 25 - L), where the signal (R - L) that is sent out isdUMUÉÍ _____ l «HMMMallBamtBB ___ iÉ¡haBri__ limits in band by filter 582. Filter 582 is also illustrated as a capacitor. The transducers 576 and 578 are arranged to take maximum advantage of the desired effect that is provided by their particular acoustic output. In• Particularly, the transducer 576 is arranged to radiate the right channel signal fed in band in a substantially horizontal direction. Preferably, the right-side speaker 504 is arranged such that the transducer 576 substantially radiates the direction of thelistener 28. This provides location indication to the listener 28. In contrast, the right-side speaker 504 is also configured such that the transducer 578 radiates the band-fed acoustic output (R-L) in a vertical upward direction . This provides alimited sense of nonsonic amplitude in the listening area. Figure 4a shows a pair of first order high pass networks, to implement high pass filtering in the signals that are fed to the side speaker• left 20 102 (202) and right side speaker 104 (204) of Figures 2 and 3. The left high pass filter 118(218) and the right high pass filter 120 (220), include capacitors 150 and 152, respectively connected in series with side horns 102 (202) and 104 (204). Thisfiltering configuration is referred to as high-pass filtering of the first order. Figure 4b demonstrates the left high pass filter 118 (218) and the right high pass filter 120 (220) implemented as second order high pass networks. The capacitors 154 and 156 are connected in series with the positive terminals of the side horns 102 (202) and 104 (204) respectively and inductors 158 and 160 are connected in shunt through the positive and negative terminals of the side horns 102 ( 202) and 104 (204). The operation of the high-pass networks illustrated in Figures 4a and 4b is well understood by those skilled in the art and will not be expressed here. It will further be recognized by a person skilled in the art that high-pass filters 118 (218) and 120 (220) may be implemented in any of a number of configurations known in the art. The use of passive high pass filter is easily recognized as an approach to signals with band limitation. In addition, it will be recognized by a person skilled in the art that the cutoff frequency may be varied according to the particular implementation desired. The bandwidth limitation of the frequency range of the signals fed to the side horns 102 (202) and 104 (204) substantially withdraws dialogue location indication from the side horns 102 (202) and 104 (204), in such a way that indication of the primary dialogue location is only reproduced by the central speaker 106 (206) that is in proximity with the video image. The lateral loudspeakers with bandwidth limitation 102 (202) and 104 (204) cut the location of the dialogue to the location of the central speaker 106, since the central channel becomes the only speaker in the system that reproduces the location indications. of fundamental dialogue. The left side speaker 102 (202) and the right side speaker 104 (204) reproduce higher frequency information of left and right channel respectively, which is generally greater than the frequency range of the primary speech. The side horns 102 (202) and 104 (204), in this way give to provide an implemented sense of amplitude without altering the location of speech sounds. It has been shown through numerous studies of concert hall acoustics that a sense of amplitude correlates with the presence of lateral reflections. That is, the amplitude correlates with the energy that arrives in the listening position from the sides of the listening space. Locating side horns 102 (202) and 104 (204) on the sides of the listening room and orienting the main radiation axis vertically upwards, allows side horns 102 (202) and 104 (204)my thousand il? í n II-, n ail ^ A ^ tt ^ É ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ in this way improving the amplitude. Additionally, because the side horns 102 (202) and 104 (204) of the present invention are limited in band to significantly reduce the indication of dialogue location, they can move more to the sides of the listener than traditional speakers. Furthermore, because the side horns 102 (202) and 104 (204) are band-limited, the increased displacement does not cause 10 distracting sound images to the sides of the listener as would occur if full-range side frequency speakers are will be placed on these sites. This allows the side speakers to be placed for maximum amplitude without generating distracting sound images. 15 An additional benefit to band limitation of side speakers is that their physical size may be relatively small. Band limitation of the side speakers at approximately 1 KHz presents a • very different configuration than the satellite / sub-20 speaker systems for typical bass. In most satellite / subwoofer systems, satellite speakers operate over a much higher frequency range, typically at a value as low as 150 Hz. These horns are therefore required to be much larger than the side horns of the present invention, in order toitiiii-i i i • juaumma, generate enough energy at these lower frequencies. In the present invention, the side horns reproduce a much more restricted frequency range. Figure 5a illustrates a central speaker 106 (206)• 5 consisting of a dual voice coil 114a and 114b (214a and 214b) and single transducer 115 (215) as illustrated in Figures 2 and 3. The amplified left channel signal is applied to voice coil 114a (214a) ) and the amplified right channel signal is applied to the voice horn 114a 10 (214b). In this configuration, the left and right channel signals are added electromagnetically inside• of the transducer 115 (215). Another particular advantage of this invention can be demonstrated with particular regard to Figure 5a. In Figure 5a, the left and right channel signals output from the respective amplifiers 112 and 116 each apply individually to the voice coil 114a and 114b of the transducer 115 to electromagnetically create the sum signal (L + R). The horn is illustrated in Figure 5a ofThis way generates the sum signal in passive form, without the need for a resistor divider network that would consume energy and contribute cost and complexity to the system. These energy or power savings are particularly relevant when the invention described herein obtains theleft and right channel signals from a relatively low power amplifier source, such as a typical stereo television set or boom box type portable stereo speakers with resonance. The left sum more right within• 5 the horn itself avoids the requirement by external parties and their associated costs. In the alternate center channel configuration shown in Figure 5b, left and right channel signals excite left and right transducersindividual 118 and 119. The left channel amplified signal excites voice coil 114a (214a) which in turn• excites or directs the left transducer 117. The amplified signal of right channel directs the voice coil 114b (214b) which in turn directs the transducer 119. 15 It will be noted that in the configuration of theFigures 5b, transducers 117 and 119 should be located in relatively close proximity such that the outputs of both transducers 117 and 119 add up^ acoustically over a maximum possible frequency range.

The effective acoustic sum requires that the two transducers are located within approximately V of the wavelength of each other. This proximity is not achieved practically over the entire range of audible frequency. At higher frequencies, some comb filtering will occur inthe combined acoustic output of the two transducers. In the case of a monophonic signal, because both transducers radiate the same signal and move in space, the resulting path length difference between the listening location and each transducer becomes an appreciable fraction of a length of wave, or multiple wavelengths at higher frequencies. Minimizing the spacing between the two elements, in this way minimizes the amount of comb filtering that occurs. Figure 6 illustrates two alternate modes for obtaining the difference signal (L-R) of the rear horn 108 (208) of Figures 2 and 3. The difference signal typically contains surround and surround sound information. Figure 6a illustrates a circuit diagram 15 for a preferred embodiment, to obtain the signal (L-R) in a passive system. The left channel amplifier 112 (212) outputs an amplified left channel signal that is fed to the positive "." Terminal of the voice coil 130 of the rear speaker 108 (208) and the right channel amplifier 116. (216) outputs an amplified right channel signal to the negative terminal of the voice coil 130. The rear speaker 108 (208) in this manner outputs audio in response to the difference between the left channel and the left channel signals. right (L - R) through transducer 134. Figure 6, .., fcMtmM ^ ..,.illustrates a circuit diagram for an alternate configuration, to obtain a difference signal (L-R). The rear speaker 108 includes dual voice coils 132a and 132b. The voice coil 132a receives on its positive terminal the amplified left channel signal of the left channel amplifier 112 (212). The terminal of the voice horn 132a is connected to the negative terminal of the left channel amplifier 112 (212). The voice coil 132b receives the amplified right channel signal from the right channel amplifier 116 (216) at its negative terminal, and the positive terminal of the voice coil 132b is connected to the negative terminal of the right channel amplifier 116 (216). ). In this way, this configuration inverts the polarity of the connection, such that the transducer 134 outputs a resultant signal (L-R). Figure 7 illustrates a third preferred embodiment of the present invention wherein a home theater loudspeaker system 300 employs low level signal processing prior to amplification by amplifier 302 and amplifier 304. The positive signal of left channel 306 and positive signal from right channel 308 feed in addition amplifier 310, any number of sum amplifiers to electronically add signals of which are known in the art. The output of the summing amplifier 310 provides a summing signal (L + R) which in turn is fed to the power amplifier 302. The positive output of the amplifier 302 supplies an amplified signal (L + R) to the positive terminal of the amplifier. central speaker 312. The negative terminal of the central speaker 312 is connected to the negative terminal of the amplifier 302. The positive terminal of the power amplifier 302 also outputs an exciting signal to the positive terminal of the subwoofer 314. bass subwoofer 314 comprises a single transducer and voice coil, similar to central speaker 312, because the signal (L + R) directs the subwoofer for bass 314, the subwoofer for bass 314 requires only a simple voice coil and transducer to output the low frequency portions of the left and right signals. It will be recognized by a person skilled in the art that alternate subwoofer configurations for particular bass may be employed with the present invention, with minimal effect on the operation of the system. The perimeter sound system 300 also actively provides a difference signal. Before amplification by the amplifier 304, the left channel positive signal 304, and the left channel positive signal 308 and the right channel positive signal 306 feed the differential amplifier 316. The output of the difference amplifier 316 outputs a signal of difference left less right (L - R). This difference signal (L-R) is fed to the power amplifier 304. The positive output of the power amplifier 304 in turn directs the positive terminal of the rear speaker 318. The negative terminal of the rear speaker 318 is connected to the negative terminal of the power amplifier 304. In this way, the output signal (L-R) by the amplifier 304 directs the rear speaker 318. The positive terminal of the amplifier 304 also outputs a control signal to the positive terminal of the amplifier 304. the left-side speaker 320 through the high-pass filter 324. The negative terminal of the left-side speaker 320 is connected to the negative terminal of the power amplifier 304. Similarly, the positive terminal of the power amplifier 304 outputs an exciting signal to the negative terminal of the right-hand speaker 322, through the high-pass filter 326. The positive terminal of the right-hand speaker 322 is connected to n the negative terminal of the power amplifier 304. The connection to the left side speaker 320 provides a resultant control signal (L-R) to the speaker. The connection to the right side speaker 322 provides a resulting signal (R-L) to the speaker. The"~ ** - * -» - ** A-. * - _1Jlllj1J_j_jnm) a :: j_ polarities of the signals applied to each of the left side speaker 320, right side speaker 322 and rear speaker 318 can inverted and the system will provide the same effect All possible permutations • 5 of the relative polarity connections of the difference signal to the two side horns and the rear speaker are also acceptable and provide satisfactory results: High pass filters 324 and 326 they operate as described above with respect to Figures 2 and 10 3. This configuration leads particularly to an energized variation where the interconnect module can include an internal amplifier to amplify the power supply signals and output the electrical signals amplified to direct the respective loudspeakers A particularly advantageous feature of an internally energized interconnection module There are options to amplify the output signals asymmetrically, so that speakers that require more energy to operate successfully receive higher energized power signals. For example, the addition signal feed to the center and bass horns can be outputted at a nominal power much higher than the signal output 25 difference to satellite and environment speakers* • - * - - - * **** - * '• -posterior. This approach provides the high power to direct the bass and front speakers, while leaving less but enough power to control or direct the side and rear speakers. For example, instead of a 10-watt stereo amplifier configuration plus 10 watts, an 18-watt amp configuration plus two watts can be used to more efficiently use the available power. Figure 8 illustrates a fourth preferred embodiment of the present invention. The home theater surround sound system (surround sound system) 400 of Figure 8 employs components similar to those used in the surround sound system 100 of Figure 2 and similar components will refer to using reference numbers starting with 400 instead of 100. The perimeter system 400 of Figure 8 is configured similarly to Figure 2 except that it receives and outputs a monophonic signal instead of the left and right component channel signals of a signal in stereo. The perimeter sound system 200 includes a left side satellite horn 402 (satellite or left-side speaker) a right-side satellite horn 404 (satellite or right-side speaker), center horn 406, rear or surround horn 408 and sub-speakers loudspeaker 410. The amplifier 412 receives a monophonic signal and outputs an amplified monophonic signal which is fed to the positive terminal of the voice coil 414 of the central speaker 406. The negative terminal of the voice coil 414 • 5 of the central speaker 406, connects to the negative terminal of the amplifier 414. The voice coil 414 of the central speaker 406 directs the transducer 415 to output sound from the central speaker 406. The positive terminal of the amplifier 412 also sends out an amplified signal 10 to the positive terminal of the left-hand horn 402, through the filter 418 and right-hand horn 404, through the filt 420. The left side speaker 402 and the right side speaker 404 are bandlimited to reproduce only higher frequencies, as illustrated using the left high pass filter 418 and the right high pass filter 420, which operate as It was previously described here. The perimeter sound system 400 also includes a rear speaker 408 that receives the amplified output 20 of the amplifier 412. The rear speaker 408 also includes a potentiometer that provides a path to ground the amplified signal that is fed to the rear speaker 408. The potentiometer 409 allows adjustment of the acoustic output of the rear speaker 25 with respect to the output of the other speakers in the system.- ^^^ j ^^^^^^^^^^^^^^^^^^^^^^^^^^^ - ^^^^^^^^^^ sgj ^ gfeww ^ - ^ The rear speaker 408 is preferably adjusted such that the level of sound pressure that it produces at the listener's site is below that produced by the front speaker 415 at that site. This causes the listener to perceive dialogue from the front stage according to the preceding effect of the sound reproduction. That is, as between two similar sounds, the human hearing process interprets the direction from which a sound arrives first as the direction from which both sounds come. Due to the psychoacoustic phenomena known as compensation with intensity of time, the sounds of higher level are perceived by the listener as they arrived earlier. Therefore, by varying the output of the rear speaker 408 to a level sufficiently below that of the front speaker 406, the sonic image is perceived as forward, but the acoustic energy of the rear speaker 408 provides additional acoustic information. The hearing process interprets the additional information as perimetric or ambient sound. It will also be recognized that level adjustment can be achieved by any of a number of approaches known to those skilled in the art. In addition, because the embodiments of Figure 8 use only one explanation channel compared to two for a stereo configuration, the listener will typically increase the total volume of the system to achieve the desired sound pressure level. As an extension to the fourth embodiment illustrated in Figure 8, a similar result can• 5 achieved by applying a monophonic signal to the amplifier 212 of Figure 3a, without power signal applied to the positive limitation of the amplifier 216. This arrangement similarly provides a surround sound effect based on a monophonic feed signal 10 and provides flexibility of a perimetric sound system configured in Figure 3a for use with both stereo and monophonic signals. A particularly convenient feature of most perimetric sound systems is the ease of installation and operation to avoid discouraging use by non-technical consumers. This invention solves most of the installation difficulties by providing a module of^^ home theater interconnection 14, with plugs of^^ 20 connection that confine the system to one and only one possible set of speaker connections for the particular modes where the difference signals (L - R) are output to the side speakers. Figure 9 is a wiring diagram showing the plugs ofinterconnection with the interconnection module 14 of Figure 1 and will be described with reference to the components discussed in Figure 1. The interconnection module 14 includes a four-terminal power plug 30 for receiving the • 5 left channel signals and right of components that are fed to the interconnection module 14 of the television 12. The left and right channel signals are received by a four-conductor wire that terminates in a four-terminal connector that couples approximately 10 with the four-way power plug. terminals 30. The negative feeds to the left and right channels are linked together within the interconnection module 14, to provide a common left signal for each of the power and output connections. The output to the central speaker 20 (of Figure 2) is provided by a three-terminal output plug 32. The three terminals of the output plug 32 provide outputs that complete the left channel • signal, the right channel signal and the output signal. 20 common ground signal. A second sub-speaker output jack for three-terminal bass 34, provides output signals similar to the sub-speaker for bass 18. The sub-speaker output jack for bass 34 similarly provides the left channel signal, the signal of channel 25 right and a common left signal at the terminals"* - * * ¿** ~ * £ ~ *** ~ * - ~ respective A trio of two-terminal output plugs 36a, 36b, 36c provides the left channel signal in one terminal and the right channel signal of the other• 5 terminal. Each of these plugs interconnects with cables that in turn connect to one of the rear speakers 26, the left satellite horn 22 and the right satellite horn 24. The resulting signal that is provided to these speakers is the difference signalleft minus right. The configuration of the interconnection module 14 in this manner is particularly adapted to the preferred embodiment shown in Figure 3a, where the left satellite horn 22, the right satellite horn 24 and the rear horn 26 have the signals ofdifference as feeds. It will be recognized by the person skilled in the art that the output plug 36a, 36b and 36c are interchangeable because each of the outputs are substantially identical signals.

^^ One of the characteristics particularlyAdvantageous of the interconnection module 14 is that the central speaker output socket 32 and the subwoofer output socket 34 can be identical sockets that output identical signals on each terminal. In this way, during installation, the operator caninstall the system in only one configuration. The operator can not connect the cable connector (not shown) for the center speaker 20 or the rear speaker 26 to one of the output sockets 36a, 36b or 36c. Similarly, the output plugs 36a, 36b and 36c result in signals• 5 identical in each terminal. These, all output sockets similarly (and input) provide (receive) the same signals. Similarly, the operator can not connect the cable connector for the satellite speakers or rear with the output jack of the satellite.center speaker 32 or subwoofer output plug 34. The operator can only connect the cable connector to one of the outgoing output jacks or signals appropriate for a particular speaker. In addition, the particular operation of the invention facilitatesconfigure the interconnection module 14, to allow ease of installation. Another particularly advantageous feature of the present invention is that the interconnect module 14 is particularly adaptable for 2, 3 and 4 standard builder cables which facilitate low cost manufacturing due to the use of readily available parts. An improvement for any perimeter home theater sound system results from reducing the number of components. An approach to the reduction of componentsis to consolidate components when possible. For example, with reference to Figure 1, the interconnect module 14 and the subwoofer 18 can logically be consolidated into a single component. Figure 10 illustrates this alternate configuration for the home theater surround sound speaker system 10 of Figure 1. The home theater surround sound speaker system (surround sound system 10 'of Figure 10, available similarly in Figure 1, and the reference numbers in Figure 10 refer to similar components of Figure 1. As can be seen in Figure 10, television 12 outputs an audio signal to the interconnect module and base speaker integral subwoofer 40 (integral base unit) The integral base unit 40 performs the combined function of the interconnect module 14 and bass subwoofer 18 of Figure 1. The interconnect module 14 has been incorporated into the housing of the subwoofer base speaker for bass, in order to reduce the number of parts and wiring requirements and also facilitate installation.The integral base unit 40 includes an interconnection portion n for distributing appropriate signals to each of the center speaker front 20, left 22 satellite speaker, right 24 satellite horn and horn back room 26. The integral base unit 40 also includes a sub-woofer directly wiring circuits"* * ---- * - * interconnection housed in the integral base unit 40. In this way, the system requires one less cable (between the interconnect module and the base subwoofer speaker for bass) and also requires a individual component• 5 or autonomous less (the interconnection module). Figure 11 illustrates an exemplary perspective view of the integral base unit .40. The integral base unit 40 includes an interconnection module 42 having disposable power and output plugs for receivingthe input audio signal and distribute the left and right signals and difference to the speakers• appropriate. The interconnection module 42 includes a four-terminal power plug 44, for receiving by a four-wire wire, theleft and right channel signals. The interconnect module 42 also includes an output plug for three-terminal central speaker 46 and a trio of two-terminal outlet plugs 48a, 48b and 48c. The interconnection module 42 is arranged similarly to the interconnection ^ * 20 module 14 of Figure 9, and the principles discussed with respect to the Figure apply equally to Figure 12. A particular difference between the interconnection module 42 of Figure 12 and the moduleinterconnection 14 of Figure 9 is because the interconnection module 42 is integrally housed with the subwoofer base speaker for bass, the interconnect module 42 does not require a subwoofer output jack for bass (such as the module of interconnection 14 of Figure 9). The• 5 left channel signal, right channel signal and common ground signal, are fed directly to the crossover network of the integral subwoofer unit 40. A particular advantage of an additional alternative embodiment of this invention solves acommon problem of many typical consumer observation rooms that do not lead to easy module wiring• interconnection to the respective rear and satellite environment speakers. Typically, wiring home theater surround sound systems requires running cableson the walls around the sides and back and around the back of the room or drill through the floor and pass the cable underneath the observation room and feedback to the observation room in the respective sites of the speakers . This invention particularly leads to a speaker communication system with wireless home theater surround sound 50, as illustrated in Figure 13. A television 51 provides the left and right channels of an audio and stereo signal to theinterconnection module 52. The interconnection module 52 distributes the left and right channel signals to the appropriate speakers in order to effect the desired system. In the embodiment shown in Figure 13, the interconnect module 52 is wired directly from the television 51, the front center speaker 54 and the subwoofer 70. In order to transmit the audio signals to the appropriate speakers, the module interconnection 52 also includes a transmitter 56 for sending an audio signal to the left satellite horn 64, right satellite horn 66 and rear ambient horn 68. Each of the speakers 64, 66 and 68 includes a receiver 56 ', for receiving the broadcast of the output signal by the transmitter of the interconnection module 52. The receiver 56 'receives the transmitted signal and transposes the signal into a suitable audio signal for its respective speakers. It will be understood by the person skilled in the art that the receiver 56 'can be configured to output the transposed signal to an amplifier prior to application of the speakers. The transmitter 56 and the receiver 56 'preferably operate on a single channel. In order to use a single channel transmitter / receiver configuration, the interconnect module 52 preferably outputs only one audio signal to each speaker. In order to achieve this convenient configuration, the speaker system of* "* * * - ^^ * fc» > - home theater surround sound 300 of Figure 7 will be the preferred embodiment of the wireless surround sound system 50 of Figure 3. In this embodiment, the Interconnection module 52 performs addition and subtraction of active signal (as described with respect to Figure 7) to generate the difference and sum signals before transmission to the respective speakers.This configuration will limit the wireless system to a single channel communication , instead of multi-channel communication, furthermore, it will be recognized by a person skilled in the art that because the left satellite horn 320, the right satellite horn 322 and the rear horn 318 is substantially directed by identical difference signals, the interconnection module 52 can use a transmitter (56) for example (to transmit an audio and control signal to each of the speakers, in this way resulting in in substantial cost savings. It will also be recognized by a person skilled in the art that receivers and transmitters configured in a similar manner can be used to wirelessly connect component horns that have been described herein as direct wiring. From the foregoing, it can be seen that this invention solves the various problems encountered in the art.. '? l, 4 ».at.-.prior and satisfies the various objectives of the invention. This invention in this way provides an effective, inexpensive and easy to install perimeter home theater sound system. The front, rear speakers• 5 left, right and bass, provide the desired sound outputs in response to application of the appropriate sum and difference signals resulting from the combination of the left and right channel signals of a stereo signal. The sum and difference signal provide theambient audio and desired dialogue in the appropriate speaker. Although the invention has been described with reference• Particular to certain preferred embodiments thereof, variations and modifications may be effected within the spirit and scope of the following claims. fifteen

Claims (1)

1. CLAIMS 1.- A speaker system to reproduce a stereo audio signal generated by an audio signal source having a left channel signal L and • a right channel signal R, characterized in that it comprises: first left channel filter means for filtering the left channel signal 'L, in order to substantially eliminate acoustic frequencies below a predetermined threshold; second channel filter media 10 left to filter a left difference signal, i- to eliminate substantially low and medium range acoustic frequencies, the left difference signal is defined as a difference between the left channel signal L and the right channel signal R; a speaker 15 left satellite to provide an acoustic output, the left satellite horn has a first and a second audio output sources, wherein the first audio output source provides an acoustic output ^^ in response to the filtered left channel signal and the The second audio output source provides an acoustic output in response to the left filtered difference signal; first right channel filter means to filter the right channel signal R to substantially eliminate acoustic frequencies below a 25 predetermined threshold; and second channel filter media Jump right to filter a right channel signal to eliminate a right channel signal, to substantially eliminate low and medium range acoustic frequencies, the right difference signal defined as a • 5 difference between the right channel signal R and the left channel signal L; and a right satellite horn to provide an acoustic output, the right satellite horn has a first and a second audio output sources, where the first audio output source 10 provides an acoustic output in response to the filtered right channel signal and the second audio output source provides an acoustic output in response to the right filtered difference signal. 2. - The device in accordance with the 15 claim 1, characterized in that: the left difference signal is further defined as the right channel signal R which is subtracted from the left channel signal L; and the right difference signal is also ^ _ defined as the left channel signal L that is subtracted from 20 the right channel signal R. 3. - The apparatus according to claim 1, characterized in that: the left difference signal is further defined as the left channel signal L which is subtracted from the channel signal 25 right R; and the right difference signal is further defined as the right channel signal R that is subtracted from the left channel signal L. 4. The apparatus according to claim 1, characterized in that it further comprises: a front speaker to provide a acoustic output in response to a power signal (L + R); a rear speaker to provide an acoustic output in response to a power signal which is defined as a difference between the left and right channels; a bass speaker to provide low frequency acoustic output in response to the power signal (L + R). 5. The apparatus according to claim 1, characterized in that it further comprises an amplifier for receiving and amplifying the stereophonic audio signals of left and right channel before application to the respective speakers. 6. The apparatus according to claim 1, characterized in that the second left and right channel filter means for filtering the power supply to the left and right satellite horns are substantially identical and also comprise first order filters. 7. - The apparatus according to claim 1, characterized in that the first left channel filter means also substantially eliminate low and medium range frequencies and the first right channel filter means further eliminate substantially low and low range acoustic frequencies. medium . • The device according to claim 7, characterized in that the first left channel filter means, the second left channel filter means and the respective first right channel filter means and the second filter means of 10 right channel, they are substantially similar. 9. The apparatus in accordance with the • claim 1, characterized in that the first left channel filter means and the first right channel filter means comprise first order filters 15 which are substantially similar and the second left channel filter means and the second right channel filter means comprise first order filters and are substantially similar. 10. The apparatus according to claim 1, characterized in that the first left channel filter means and the first right channel filter means have a first bandwidth and the second left channel filter means and the second right channel filter means have a 25 second bandwidth. _- ^ __ ^ _ 12. - The apparatus according to claim 11, characterized in that the first left channel filter means and the first right channel filter means are substantially similar and • 5 further comprise second order filters, and the second left channel filter means and the second right channel filter means are substantially similar and further comprise second order filters. 13.- A speaker system to reproduce a 10 stereophonic audio signal generated by an audio signal source having a left channel signal L and • a right channel signal R, characterized in that it comprises: first left channel filter means for filtering the left channel signal L in order to 15 substantially eliminate acoustic frequencies below a predetermined threshold; second left channel filter means for filtering a left difference signal, to substantially eliminate low and medium range acoustic frequencies, the left difference signal ^^ 20 is defined as a difference between the left channel signal L and the signal of right channel R; a left satellite horn to provide an acoustic output, the left satellite horn has a first and a second audio output source, where the first The audio output source provides an acoustic output in response to the first filtered left channel signal and the second audio output source provides an acoustic output in response to the left filtered difference signal; first channel filter media • 5 right to filter the right channel signal R, to substantially eliminate acoustic frequencies below a predetermined threshold; second right channel filter means to filter a right difference signal to filter a right channel signal to eliminate 10 substantially low and medium range acoustic frequencies, the right difference signal defined as a difference between the right channel signal R and the left channel signal L; a right satellite horn to provide an acoustic output, the satellite horn 15 right has a first and a second audio output sources, wherein the first audio output source provides an acoustic output in response to the first filtered right channel signal and the second audio output source provides an acoustic output in • 20 response to the right filtered difference signal; a front speaker to provide an acoustic output in response to a power signal (L + R); a rear speaker to provide an acoustic output in response to a power signal that is defined as 25 a difference between the left and right channels; and a bass speaker to provide low frequency acoustic output in response to the power signal (L + R). 14. The apparatus according to claim 13, characterized in that: the signal of • 5 left difference is also defined as the right channel signal R that is subtracted from the left channel signal L; and the right difference signal is further defined as the left channel signal L which is subtracted from the right channel signal R. 10 15. The apparatus according to claim 14, characterized in that the first left channel filter means. and the first right channel filter means comprise first order filters and are substantially similar and the second left channel filter means and the second right channel filter means comprise first order filters and are substantially similar. 16.- The apparatus in accordance with the ^^ claim 13, characterized in that the first means ^^ 20 of the left channel filter also substantially eliminate low and medium range frequencies, and the first right channel filter means also substantially eliminate low and medium range acoustic frequencies. 17. The apparatus according to claim 16, characterized in that the first left channel filter means and the first right channel filter means have a first bandwidth and the second left channel filter means and the first ones are second left channel filter means have a second bandwidth. 18. The apparatus according to claim 13, characterized in that the first left channel filter means and the first right channel filter means have a first bandwidth, the second left channel filter means and the second ones Right channel filter media have a second bandwidth. 19. The apparatus according to claim 18, characterized in that the first bandwidth is greater than the second bandwidth.