JPH114500A - Home theater surround-sound speaker system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain a 3-dimension sound field which provides a grandiose sense with consistency, to provide a video image for viewers in the entire viewing area, while conversations are concentrated on a video screen as well as to form a sound field with realism and presence. SOLUTION: This system 10 reproduces sound (especially, sounds based on a stereo signal including conversations accompanying video image) with realism. The system 10 is placed in the vicinity of a video image and has a front middle loudspeaker 20, that outputs an acoustic output based on a sum signal of left/ right channel components of an audio signal. A rear speaker 26 is placed behind an audio-visual area and provides an outputs of an acoustic output, based on a difference signal (L-R) or (R-L) of the left and right channels. Left/right satellite speakers 22, 24 are placed respectively to the left/right of the audio-visual area. The left right satellite speakers 22, 24 respectively reproduce the audio signal for left/right channels.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to the reproduction of stereo sound, and more particularly, to the reproduction of stereo sound associated with a video image so that the conversation is focused on the video image, and to the viewer ( Listener) has a realistic (or immersive) 3D sound field (soun
d) reproducing the stereo sound associated with the video image such that the environment (atmosphere) and the sound effects are reproduced in a manner that makes the user feel as if they are in the d field.

[0002]

BACKGROUND OF THE INVENTION In the past, a number of monaural and stereo sound systems have been developed for sound reproduction with high reproduction fidelity. Early attempts, efforts and research have neglected the concept of reproducing fidelity audio sound in a monaural manner. That is, in early attempts and studies, measurable acoustic properties (eg, frequency response,
The focus has been on producing speaker enclosures (speaker enclosures, casings) that meet performance criteria (reproduction conditions) and criteria determined by distortion and dynamic range). The loudspeaker comprises an enclosure containing one or more acoustic transducers and crossover networks for reproducing sound in the entire audio frequency range. A three-way loudspeaker system which is an example of such a multi-transducer crossover network structure includes a woofer transducer for reproducing low-frequency sound, a mid-range transducer for reproducing medium-frequency sound, and a tweeter transducer for reproducing high-frequency sound. And

A typical crossover network described above is to smoothly transition the acoustic output of one transducer to the acoustic output of another by blending (combining) the acoustic outputs of a plurality of speaker transducers. To achieve a good tone balance characterized by One way to achieve such good tone balance is to employ a symmetrical crossover network, which acts as a filter. This filter is to ensure a response drop-off of one transducer. Because the transition area (transition r
The rise in frequency at egion) is a mirror image of the increased response of the accompanying transducer that reproduces the nearby high frequency band of the sound. Proper implementation of this structure / configuration requires that no audible artificial sound (unnatural sound quality) be produced by the combination of the plurality of transducers and the crossover network. Audible artificial sounds (unnatural sound quality) are caused by irregular frequency responses and phase cancellation effects. The occurrence of irregular frequency responses and the like may be due to housing multiple transducers in one speaker enclosure.

A monaural audible sound signal / audio signal (au
The earlier attempts to achieve high fidelity reproduction with a dio signal) and a three-way crossover network gradually gave way to stereo sound reproduction. Early stereo systems provided a pair of identical high-fidelity speakers spatially separated and reproduced two-channel audible signals. This spatial separation of the two speaker enclosures is fundamental to the concept of stereo sound reproduction. The stereo image is obtained by fusing the sound output from the pair of speakers to create a horizontal panorama of sound.
Occurs when one stereo image is perceived as ama of sound. This sound panorama forms a stereo sound image that spans the space between the two speakers for the viewer (listener). A suitable stereo effect extends between the two speakers and
It is experienced by a viewer located along a line perpendicular to the plane of the speaker.

[0005] Most loudspeakers incorporated into stereo systems emit sound linearly from the loudspeakers to the viewer (called direct radiation). To expand the stereo image, designers have used pairs of speakers that emit (emit) a combination of direct and reflected sound. With such a structure, the stereo image extends beyond the space between the two speakers.

[0006] Some more modern stereo sound systems have a three-piece sub-satellite.
sub-satellite) The speaker system is adopted. In this system, the conventional pair of full ranges (fu
Instead of a speaker enclosure, a combination of a sub-woofer bass unit and a pair of satellite speakers is used. In such a three-piece loudspeaker system, the satellite speakers reproduce a wide range of medium and high frequency sounds, and the bass unit reproduces only very low frequency sounds. Since the bass (bass) is reproduced only by the subwoofer bus unit, the satellite speakers can be made relatively small as compared with the traditional large-sized stereo speaker box. The traditional speaker box was forced to be large in size due to the large transducers and enclosure required to achieve good bass response. Many consumers prefer the small satellite speaker structure over such a traditional pair of full-range speaker enclosures. The bass unit can be located out of sight, and the satellite speakers can be more easily adapted (integrated and integrated) to the interior decoration. However, other consumers find it difficult to install the above-mentioned somewhat small satellite speaker box so that it does not enter the field of view and does not interfere with objects and decorations in the house. .

[0007] Although the overall sound quality of loudspeakers has been improved in modern times, the generality of the most sophisticated systems (whether it is a pair of stereo speakers or a three-piece sub-satellite loudspeaker system). Even with great sound quality improvements, many consumers find that modern sound systems lack the sonic realism and ambience associated with live sound. Each sound reproduction system satisfies the quantitative sound performance (sound reproduction) conditions regarding frequency response, distortion, and dynamic range, but has a wide range of sonic realism (acoustic realism / realism) from a qualitative viewpoint. Dissatisfaction with the audience in the area. Some systems, designed to produce more realistic sound, have a spacious, magnificent, and relaxed (spacing)
It is known that iousness can be felt.
Such a design is a major advance in the acoustics field in improving the spatial quality of the reproduced sound and avoiding the generation of (unnatural) artificial sounds that detract from the overall sonic experience. Was the basis of

The above-described three-piece sub-satellite speaker system extends the concept of spatially separating and dispersing speaker components (such as a pair of stereo speakers). This concept can be further extended by spatially distributing a significant number of point sources that reproduce sound in a listening environment to further increase perceived majesty. I can do it. By adding multiple spatially distributed sound sources, the magnificence can be more perceived, but on the other hand, an exaggerated and slightly over-spatial feel is created. It has no realism and presence. Such unnatural sound reproduction often causes the viewer to feel acoustic fatigue. Thus, to fully satisfy the viewer, the enhanced majesty must be balanced with the perceived acoustic realism of the sound field being created.

This balance is particularly important in the case of home theater (in home theater) sound systems. This is because the acoustic conditions (required requirements) of the home theater sound system are different from the acoustic conditions of sound reproduction of stereo music. The important objectives of a home theater sound system are: (1) a convincing surround sound acoustic atmosphere based on the ambience and sound effect audio signals captured in the soundtrack; ), (2) maintaining a stereo image panorama of the sound in front of the viewer, and (3) reproducing the conversation focused on the video screen to all viewers in the room. In short, satisfactory acoustic performance (sound reproduction) refers to a sound field having a three-dimensional spatial quality that a viewer can perceive as authentic in relation to a visual image on a video screen. You can do it when you are in

[0010] Earlier attempts to create home theater sound involved placing a pair of traditional speakers on either side of a centrally located video display. Such a system can sound better than the sound of the speakers built into a typical television.
However, the performance of such systems has been unacceptable in the market for at least two reasons. The first reason is that for a viewer who is not on the center line between the two speakers, the conversation does not seem to be concentrated on the screen (ie, the conversation does not seem to come from the screen only). Conversations are usually evenly recorded in the left and right channel signals. Therefore, the place where the conversation is concentrated is a point at an equal distance from the two speakers. That is, only the viewer on the center line between the two speakers can perceive the concentration of the conversation. If the viewer deviates from the center line, the viewer approaches one speaker,
Move away from the other speaker. The concentration of the conversation shifts in the direction from which the first signal arrived. That is, it shifts to the closer speaker. As the viewer moves off of the center line, the conversation wither / collapses / collapses / collapses with the closer speaker. For a viewer who is not on the center line, the concentration of the conversation moves from the position of the video image, and the illusion that the person on the screen is actually speaking to a viewer who is not on the center line is broken. Second, a pair of stereo speakers placed on either side of the visual display confine the sound field to the space in front of the viewer in the plane defined by the two speakers. Therefore, the viewer does not experience the feeling of being in or immersed in the sound field at all. That is, they do not feel that the sound is occurring next to or behind the viewer, and sometimes in front of it.

Many systems have been developed to solve the above problems. For example, US Pat. No. 3,697,692 (inventor
The patent holder: Hafler) has been working on environmental recovery (ambience-recover).
y) The use of technology is being discussed. The above-mentioned U.S. Patent discloses that surround sound information is present in substantially all stereo audio signals (whether music recordings or soundtracks of video program material),
It takes advantage of the fact that it is recoverable. Recovery involves obtaining a difference signal (LR) between the left and right channels (substantially the ambience portion of the signal).
Only). The recovered surround sound information is provided by a difference signal (LR) obtained by subtracting the right channel signal from the left channel signal reproduced by a speaker located at the rear of the listening room.

[0012] Other early home theater sound systems improve the quality of speech sound reproduction by adding a center channel and reproducing the sum signal (L + R) of the left and right channel signals. The center channel is a left channel signal-a right channel signal (L-
R) difference signal is combined with rear surround speakers (s). This is the same as the above-mentioned environmental recovery speaker. One example of such a system is DOLBY SURR
OUND (Dolby Surround) in the United States Dolby
Developed by Laboratories.

The central speaker for reproducing the sum signal (L + R) as commercialized in the Dolby Surround system makes the effect of concentrating conversation ideal for a viewer who is not on the center line between the speakers. Has achieved results. However, the (L + R) center channel reproduction does not completely solve the problem that a viewer who is not on the center line between the loudspeakers feels a discrepancy or mismatch between the auditory image and the visual image. These systems also suffer from errors in the concentration of conversation (and the problem that other signals are encoded in the sum signal). This is because passive decoding devices such as Dolby Surround can only provide up to 3 dB of adjacent channel separation. (Here, the adjacent channels are center and right, center and left, left and surround, and right and surround.) The level difference of 3 dB between the talk of the center channel and the talk of the left and right channels is typical. It is not sufficient to limit the concentration to the position of the center channel speaker at the listening position in the entire listening room. For viewers not on the centerline between the speakers,
Concentration also shifts to the closer speaker. Collapse of the speaker with the closer speaker is a common problem with all conventional passive decryption systems.

As another example of a Dolby surround system, a T-shaped structure is proposed in US Pat. No. 4,612,663 (Holbrook, inventor and patentee). This system produces surround sound by passively combining stereo signals. The T-type system has left and right speakers for reproducing left and right signals, and is positioned between the left and right speakers and on the same plane as the left and right speakers.
-R) and a fourth speaker located behind the viewer for reproducing the difference signal.
However, this system does not provide a reasonable rational sound image if the stereo signal has energy temporarily offset to the left or right channel.
onic image) cannot be maintained. Also, in the above system, the perception that a conversation is being made from a nearer speaker (left or right speaker) cannot be prohibited.

Yet another system utilizing (LR) and (RL) difference signals is shown in US Pat. No. 5,027,403 (Short et al., Inventor and patentee). The U.S. patent describes the use of left and right channels pointing forward to produce sound output in the direction of the viewer. The U.S. Pat. No. 4,077,064 also describes redirecting and sending an (L + R) bass signal from the normal plane of the video viewing area. In addition, the U.S. patent describes directing or sending (LR) and (RL) signals from the vicinity of the video image to the rear or side. However, this US patent
It has the disadvantage that all sounds emanating from the speakers are emanating from the video image. Such near planar sound emission cannot provide the full environmental and surround sound effects.

Another example of a system having a plurality of loudspeakers in a substantially planar arrangement is disclosed in US Pat. No. 4,497,064 (Polk). This U.S. Patent also describes providing left and right main speakers and sub speakers. The sub speaker is located near the main speaker. With this arrangement, when the stereo sound is reproduced, the viewer is provided with a spacious and expanded acoustic image. However, the system of this patent requires certain strict restrictions and requirements. For example, the speakers must be equidistant from the viewer. This is to ensure that the sound reaches the viewer within a predetermined time. The U.S. patent also states that an inverted version of one main speaker signal is high-pass filtered and used as output from the opposite sub-speaker. When high-pass filtering is performed, the main speaker component on the opposite side is canceled. Without high-pass filtering, the component would reach the ears of the filtered audience. However, the high-pass filter does not cancel (remove) low frequency components in order to maintain the concentration of audio information in the video image. The above U.S. patent further requires that all system speakers must be kept approximately in the same plane and that they must radiate in the direction of the viewer. In addition, the system of this patent fails to keep the recorded program material equally on the left and right channels in the center area of the two speakers, for viewers not on the center line of the two speakers. For a viewer who is not on the center line of the two loudspeakers, such signal concentration shifts to the closer loudspeaker.

An example of a non-planar speaker arrangement is disclosed in US Pat. No. 4,443,889 (Norgaard, inventor and patentee). In this US patent, it is described that a left front speaker and a right front speaker are used to reproduce left and right channel stereo signals, respectively. Also, the above-mentioned U.S. Patent describes the use of the (LR) difference signal via a rear speaker to generate an ambient signal (ambience singal). However, among other things, the U.S. patent does not consider combining the (L + R) sum signal via a central speaker to better focus the conversation on the video image.

US Pat. No. 5,181,247 (Holl) discloses a similar concept for utilizing (LR) and (RL) difference signals. However, this patent uses a single speaker (L +
R) Outputting a sum signal is not taught. Also,
The U.S. patent includes environmental speakers.
It does not show that band limiting is performed on the signal input to the peaks.

US Pat. No. 4,819,269 (inventor and patentee: Klayman) includes a limited dispersing pattern (dispersi).
It describes emitting a sound based on a sum signal (on pattern) and emitting a sound based on a difference signal in a wide dispersion pattern. The emitted signals are acoustically combined to improve the stereo sound of the listening area. However, in this US patent,
In order to achieve the desired effect described above, an array of horn-type loudspeakers or transducers with a dedicated and special wide dispersion pattern is required. Further, in the above-mentioned U.S. Patent, the vocal energy (vocal
No mention is made of excluding the primary frequency range of any speaker from the output of any speaker.

Other surround sound type systems require complex signal processing to improve the apparent separation between left, center, right and surround channels. The most common system of this type in use today is the DOLBY PRO-LOGIC (Dolby Pro Logic) decryption system. This system improves upon the solution of the basic problem of many conventional passive decryption systems described above. Matrix-encoded using active electronics
It decodes audio signals, introduces time delays, and steers between channels via auto-gain control circuitry. However, considerable cost is required to improve performance in this way. Because the Dolby Pro Logic system has at least four
This is because two separate amplification channels are required.

Also, due to its nature, active electronic signal processing systems use artificial sound (sonic artifa) in response.
ct: unnatural sound quality that destroys realism and presence). One such artificial sound in Dolby Pro Logic systems comes from active steering circuits that vary the amount of adjacent channel signal subtracted from the signal. For example, if there is a conversation and it is desired to concentrate this conversation in the center, the center channel signal is subtracted from the left and right channel signals, removing conversation energy from these channels. This variable subtraction dynamically changes the channel separation and maintains the main concentration in a particular direction. As the conversation enters and exits the scene, the viewer frequently hears the ambience coming and going, which creates an ambience in the audio-video presentation. be able to. Shrinking down and growing back of the environment with the introduction and suspension of conversation distracts viewers. Thus, it can be seen that this active electronic signal processing system is clearly unsuitable for home theater sound reproduction.

Another problem with Dolby Pro Logic systems is that they cannot operate properly without encoded program material. Unencoded or degraded or degraded material for any reason disrupts the logic circuit and may cause unintended decoders
As they steer localization, they produce strange and extreme spatial effects. Another major drawback of active Dolby Pro Logic demultiplexing systems is that they are costly to the consumer and difficult to properly install and use the system because of its complexity. It is.

More recently, recursive attempts have been made to create less complex, low cost passive surround sound systems. One example of such a system is U.S. Pat. No. 5,386,473 (inventor and patentee: Ha
rrison). This patent discloses a line level stereo television output signal which requires further amplification to generate the high level signal required to drive the speakers.
l) using a transformer that passively combines the above. The transformer receives the input left and right channel signals and includes a front left, front right, rear left (LR), rear right (RL), center (L + R) and sub-woofer (sub-woman).
ofer) channel. This patent seeks to achieve a surround sound effect by solving the problems arising from using speakers connected to a high level amplifier output, especially by converting low level signals. However, it is difficult for the above-mentioned U.S. Patent to properly operate a passive surround sound system with a high-level signal. The present invention provides surround sound, particularly using high-level signals, and has the problems associated with the high-level systems described in the aforementioned U.S. patents (e.g., high-performance component cost, balance, etc.).
Is to solve.

Other recent attempts at passive conjugation include the QD-1 series manufactured by Dynaco.
There is an II decoder. The QD-1 Series II decoder receives a signal from a stereo amplifier. The decoder then generates four (or five) signals (for two front speakers, two rear speakers, and an optional central channel speaker). A second similar decoder is an H.RTM. Manufactured by Chase Technologies.
It is a TS-1 decoder. As with QD-1, Chas
e's decoder receives the signal from the amplifier and then generates signals for a pair of front speakers and a pair of rear speakers. Chase's decoder also produces an optional amplified center channel speaker signal.

The two passive decoders described above have two major disadvantages. The first disadvantage is that the resistor network used to generate the (L + R) signal for the center channel dissipates and dissipates energy, so the output is high enough to compensate for this energy loss. The need for a (high performance) receiver or stereo amplifier. All speakers of the system are used in portable boom-boxes or televisions of the type where no power is wasted in relatively low power amplifiers (eg, signal summing resistor networks). It is preferable to provide such a system driven by an amplifier. In one such conventional system, power must be supplied to the center channel speaker in order to achieve the desired function of maintaining conversational concentration at the physical location of the center speaker. A second drawback is that since a certain amount of (L + R) signals are provided to the rear surround speakers, the conversations originating from the rear surround speakers will include artificial sound. Therefore, the sense of realism and presence of the intended environmental effect is lost.

Therefore, in order to provide a speaker system that appeals to the market at a reasonable cost by limiting the cost of the speaker system, a surround sound for a home theater that operates using relatively simple and passive electronic components. The need for speaker systems still exists. Of particular importance in these systems is that the loudspeaker system provides a consistent (constant) ambient sound field, as well as a listening area and a viewing area.
In all the positions of a), it is necessary to keep the conversation focused on the video image. The conversation and the visual image also preferably match in the video image, and preferably do not move in the direction of the particular speaker.

In addition, audio designers have paid considerable and special attention to designing loudspeaker systems that reproduce left and right channel audio signals of stereo signals to create three-dimensional surround sound acoustics. However, audio engineers almost ignored the mono sound market. Many consumers still have a mono television, and this type of television
Only one monaural channel is output instead of the left and right channel components of the stereo signal. This allows
Consumers who currently have a monaural television can only hear sound emanating from the position of the television. Also, while AM stereo is being continuously studied and adopted by a few limited stations, most AM broadcasts continue to use monaural. In addition, many programs that can be viewed on televisions, VCRs (video cassette recorders), cables, satellite broadcasts, and other stereo audio / video signal distribution systems have mono soundtracks.

Some stereo and home theater audio / visual receivers apply signal processing techniques to monaural sound signals to simulate them.
) Creating a stereo or enhanced spatial sound effect. Such signal processing typically requires additional complex phase shifting, filtering, and digital signal processing circuitry. Thus, in order to obtain a simulated stereo or three-dimensional spatial effect from a monaural audio signal, the consumer must use a receiver such as described above,
You have to pay for purchasing a surround sound decoder or other sound processing electronics and a suitable speaker network. Therefore, there is a need for a low-cost system for efficiently reproducing monaural audio signals so as to produce satisfactory three-dimensional sound effects.

Although it is obvious that a proposal for a home theater surround sound system having all of the above advantages is desired, more realistic and theoretical problems exist in the home theater system. That is, as the home theater system continues to advance and improve, the number of separately required components usually increases. Such components often include active electronic controls, numerous speaker connection components, auxiliary control modules, and separate audio system interconnect components. Such cumbersome parts often confuse the average consumer in their installation. Despite many manufacturers' attempts to make parts installation more user-friendly and to facilitate the installation process, many users experience difficulties in attempting to properly install systems and components. The most recent attempt to facilitate the installation process has been to visually identify the connection jacks, as well as to label the connections of the speakers and audio signal sources, in addition to labeling the connection jacks, as is evident to the user. Signs and abbreviations are used. By doing so, a detailed and complete mounting procedure / method can be presented. However, for a number of reasons, the above approach has not been well accepted by consumers as a way to properly and easily install a home theater sound system. And many consumers have had to request a professional serviceman or other professional contractor to install it for a fee.

[0030] Therefore, the home theater surround, which can greatly facilitate the installation, allows the consumer to easily and accurately install and operate the system in a relatively short time, and thus has a large market appeal. There is a need to provide a sound system.

The present invention applies and utilizes various acoustic design principles in a novel manner, and separates adjacent channels (adja).
Many objectives are achieved by novel combinations of cent channel separation and individual channel operating bandwidth.

It is an object of the present invention to maintain a consistent, magnificent (constant and spacious) three-dimensional sound field, while at the same time providing a conversation on a video screen for viewers throughout the viewing area. The purpose is to form a sound field with a sense of realism and presence while providing video images to be concentrated.

Another object of the present invention is to provide a complex and expensive active electronic multi-channel surround sound matrix composite system.
It is an object of the present invention to provide a low-cost sound reproduction speaker system capable of producing a true cinema-like surround sound that is equal to or better than the surround sound of a round-sound matrix-decoding system.

Another object of the present invention is to avoid the generation of environmentally destabilizing artificial sounds associated with active electronic signal processing.
Passive separation of speech and reproduction of environmental audio signals so that images and acoustic images can be viewed at an acceptable level.

It is another object of the present invention to provide a conventional audio signal source (eg, two-bit) without using auxiliary matrix decoding electronics.
Channel stereo or matrix-encoded stereo signal)
It is to reproduce the sound with a spacious feeling.
It is another object of the present invention to provide a sound reproduction speaker system capable of producing a spatially enhanced surround sound acoustic effect even for a monaural audio signal.

It is another object of the present invention to provide a speaker system that is relatively easy and simple to install and operate for the average consumer. This includes ensuring that consumers can connect components in a relatively short time.

Another object of the present invention is to provide a speaker system that can be easily and directly connected to a stereo television without using another audio-video receiver or amplifier.

It is another object of the present invention to provide cinema surround sound at a normal home listening level using a low wattage power amplifier or the equivalent in a stereo television on the market. That is.

Another object of the present invention is to provide sufficient sound reproduction with small satellite speakers having a very small size and which can be placed invisibly in a home environment without affecting acoustic performance. It is to provide a possible speaker system.

[0040]

According to the technical idea of the present invention, a home theater surround sound speaker system is provided with an audio / video presentatio.
By playing back the stereo audio part of n) in a new way, the conversation is focused on the video image, and the viewer is in a sound field that can be perceived as a complete wall in relation to the visual image (sound field Immersed in).

In the first preferred embodiment of the present invention, the passive unpowered and passive unpowered
d) The speaker system has a front speaker, a left speaker, a right speaker, and a rear speaker, each of which receives an electric input signal and outputs an acoustic output based on the electric input signal. The front speaker is placed near the video image and the left and right (L +
R) to produce an acoustic output based on the sum. Thus, the conversation focuses on and matches the video image. The right and left speakers may be located in the same plane as the front speakers, but are preferably located between the viewer and the front speakers and to the left and right of the viewing area. The left and right speakers output sound output based on the left and right stereo channels, respectively. The rear speaker is placed behind the viewing area, and outputs an audio output based on a difference between stereo channel signals, that is, a left-right (LR) or right-left (RL) difference signal. This difference signal substantially eliminates speech, and provides environmental and surround sound audio information (ambi
ence and surround sound audio information). The left and right channel electric signal inputs respectively input to the left and right speakers are band-limited so that almost all frequency components below a predetermined threshold frequency are removed. Due to band restrictions, the conversation is concentrated on the front speakers. Because, by filtering, the audio signal range (sp
This is because the signal energy of the eech signal range is almost removed.

In a second preferred embodiment of the present invention, a passive, non-powered, non-powered speaker system includes a front speaker, a left speaker, a right speaker, and a rear speaker, each of which is electrically powered. It receives an input signal and produces an acoustic output based on the electrical input signal. The front loudspeaker is placed near the video image and provides an audio output based on the sum of the left and right (L + R) left and right channels of the stereo signal. Thus, the conversation focuses on and matches the video image. The left speaker may be located in the same plane as the front speaker, but is preferably located between the viewer and the front speaker and to the left of the viewing area. The left speaker is, for example, an electric input difference signal (L-βR)
A sound output is issued based on Where β is a gain factor that varies between 0 and 1 or 0 and 1
Is a fixed gain factor. Similarly, the right speaker is preferably located between the viewer and the front speaker and to the right of the viewing area. The right speaker outputs an acoustic output based on the difference signal (R-βL), for example. Here, β is a gain factor that changes between 0 and 1 or a gain factor that is fixed between 0 and 1. The rear speaker is placed behind the viewing area, and outputs sound based on at least one of the differences between the stereo channel signals, that is, at least one of the left-right (LR) or right-left (RL) difference signals. Put out. When this difference signal is used, the speech part of the audio signal is almost removed, so that the ambient sound (ambient so
unds) are left. In this second preferred embodiment, the difference signals input to the left and right speakers, respectively, are band limited if necessary to substantially remove all frequency components below a predetermined threshold frequency. By band limiting the difference signal, the low frequency components of the difference signal are substantially eliminated, so that the difference signal can be reproduced using a very small compact speaker.

In a third preferred embodiment of the present invention, the high powered, powered speaker system comprises a front speaker, a left speaker, a right speaker, and a rear speaker, each speaker receiving an electrical input signal. Receiving and producing an acoustic output based on the electrical input signal. By preprocessing and amplifying the left and right channels of the stereo signal with active electronic components, for example, a left + right sum signal (L + R) and a difference signal (LR) are created. Each speaker of the speaker system is driven by the obtained sum signal and difference signal. A front speaker is placed near the video image and provides an acoustic output based on the sum signal. Thus, the conversation focuses on and matches the video image. The left speaker is located on the left side of the viewing area, and outputs a sound output based on, for example, a difference signal (LR). The right speaker is located on the right side of the viewing area, and outputs a sound output based on, for example, a difference signal (RL). The rear speaker is located behind the viewing area,
A sound output is generated based on the difference signal. In this third preferred embodiment, the difference signal may be inverted by reversing the polarity applied to a particular speaker. In the third preferred embodiment, the difference signals input to the left and right speakers are band-limited, if necessary, to substantially remove all frequency components below a predetermined threshold.
Thus, the difference signal can be reproduced using a very small compact speaker.

In a fourth preferred aspect of the present invention, a speaker system has a front speaker, a left speaker, a right speaker, and a rear speaker, each speaker receiving an electrical input signal and based on a monaural electrical input signal. Produces monaural sound output. A front speaker is placed near the video image and provides an audio output based on the monaural signal. The left speaker may be located in the same plane as the front speaker, but is preferably located between the viewer and the front speaker and to the left of the viewing area. The left speaker produces a monaural sound output based on the monaural electrical input signal. Similarly, the right speaker is preferably located between the viewer and the front speaker and to the right of the viewing area. The right speaker produces a monaural sound output based on the monaural electrical input signal. The rear speaker is placed behind the viewing area and outputs a monaural sound output based on the monaural input signal. Because of the use of monaural signals, users who have only a mono audio output source can enjoy enhanced spatial sound imaging.
sonic image effects or sonic sound effects based on monaural signals. The monaural signals input to the left and right speakers are band-limited as described above, and almost all frequency components below a predetermined threshold frequency are removed. By band limiting the monaural signal, the low frequency components of the monaural signal are substantially removed, so that the signal can be reproduced using relatively small and compact satellite speakers. Also, by limiting the band, it is possible to prevent (restrict) the center speaker from reproducing the main (large) vocal energy.

The present invention also relates to a power amplifier for receiving and amplifying left and right input signals and outputting the amplified signals to the left and right speakers, respectively. In the case of a high-output and power supply type having an integrated amplifier, a system designer can generate an amplified output signal adjusted to a specific speaker selected by the system designer. According to such an integrated structure, the sound output of the system can be easily optimized.

The invention further relates to a separate (additional) bass speaker for reproducing the low frequency components of the stereo signal. The bass speaker only needs to be located somewhere in the viewing area, and outputs a sound output based on the low frequency component of the (R + L) sum signal.

The present invention also relates to an interconnect module that facilitates installation and operation by a user. The interconnect module comprises input and output jacks having a predetermined number of terminals. A predetermined number of terminals indicate what signals are input or output by that jack. For example, an output jack having three terminals outputs left, right and common grounding electrical signals, respectively. With such a structure of input and output jacks, the system can be mounted properly. Because the user is 1
This is because it is only necessary to assemble the speaker system in one specific form / method. The speaker system may have the interconnect module as an additional independent component, or the interconnect module circuit may be integrated into one of the existing components (eg, a bass speaker or a front speaker). Is also good.

The present invention also relates to making the above system wireless. When wireless, an electrical audio signal connection provides audio signals from the audio signal source to the interconnect module. The interconnect module has active electronics for generating both the difference signal and the sum signal. A wireless transmitter (transmitter) receives and transmits the difference signal. Each of the left, right and rear speakers has a radio receiver tuned to the frequency of the radio transmitter. The receiver then provides an amplified electrical signal suitable for producing an acoustic output with an associated speaker (providing an amplified electrical signal such that the associated speaker is more likely to produce an acoustic output). Other objects and advantages of the invention will be apparent to those skilled in the art from the following detailed description and claims, which should be read in conjunction with the accompanying drawings.

[0049]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

The following description of the preferred embodiments is merely illustrative, and is not intended to limit the technical scope of the present invention or its application and use. In the present specification and drawings,
Parts and elements having similar structures and operations are denoted by the same reference numerals.

The embodiment described here improves on the prior art in several respects and will first be briefly described. First, the present invention provides a spacious feeling (spacio
In order to make the viewer perceive usness), several speakers are spatially dispersed around the listening room. Spatial distributed arrangement means left and right speakers,
This includes providing rear speakers, front (or center) speakers, and subwoofers. Second, in the present invention,
By concentrating the sound emission pattern on the front or center speaker, the viewer is made to think that a certain sound comes out of that speaker. The invention also provides for ambient surround sound throughout the room.
Play a specific sound to form. Such sounds preferably originate from speakers other than the front or center speaker. Third, in the present invention, the frequency band is limited in order to remove a specific audible frequency generated by the left and right satellite speakers. The frequency for band limiting is
It is determined and selected with the intention of removing the vocal energy output from the satellite speakers. Fourth,
In the present invention, the frequency range (rang
es) overlap in unusual ways. Thus, each of the front, rear, and side speakers has a relatively wide overlap frequency range. Fifth, the present invention passively outputs the left channel, right channel, left + right channel, and left-right channel audio signals using several different types of passively generating signals. I do.

FIG. 1 schematically shows a home theater surround sound speaker system (sometimes called a “surround sound system”) 10 arranged based on the principle and technical idea of the present invention. The surround sound system 10 has a source of a suitably amplified stereo signal (shown in FIG. 1 as a television TV 12). The stereo audio source may be any of a number of audio signal sources. Thus, while the stereo audio signal source is shown here as television 12, the audio signal source may be a stereo receiver, car stereo, portable compact disc or tape player, portable boom-box type stereo (one or one). It may be a combination of a plurality of radios, a CD player and a cassette tape deck, such as a so-called cassette CD radio cassette), or any other stereo signal source.

The television 12 outputs the amplified audio signal to the interconnection module 14 via the multi-core cable 16. The multi-core cable 16 typically has two sets of conductors for transmitting the left and right channels of the stereo signal output from the television 12 to the interconnect module 14.
The interconnect module 14 converts the audio signal to the television 12
, And selectively distributes to specific components (surround) speakers of the surround sound system 10 by combining the component (running) left and right channel signals.

The component speaker typically has a subwoofer 18 that receives a full range of left and right signals but reproduces only the low frequency components of the audio signal. The interconnect module 14 also outputs audio signals to the front center speaker 20. The front center speaker 20 receives both the left and right component signals of the stereo signal and reproduces the (L + R) sum signal. Preferably, the front center speaker 20 is located near the television 12 and emits an acoustic output of a (L + R) sum signal toward a viewer (listener) 28.

The interconnection module 14 outputs a left channel signal to the left satellite speaker 22 and outputs a right channel signal to the right satellite speaker 24. The left satellite speaker 22 and the right satellite speaker 24 may be relatively small speakers and need only reproduce mid-range and / or high-frequency signals. The left and right satellite speakers are preferably oriented such that the main radiating axis of the loudspeaker points upward along a vertical axis. However, sufficient performance, performance, and performance can be obtained when the satellite speakers are oriented in other directions. The interconnect module 14 also outputs audio signals to the rear environment speakers 26. Rear environmental speaker 26
Typically receives an audio signal in the form of a left channel-right channel (LR) or right channel-left channel (RL) difference signal. As will become apparent from this detailed description, in some embodiments of the present invention described herein, the interconnect module 14 generates various signals to provide left satellite speakers 22, right satellite speakers 24 and / or Or rear environment speaker 26
Can be output to The term speaker is used for
It is first mentioned explicitly that this means a system that converts an electrical input signal into an audio output signal. Here, the system has 1
One or more crossover networks
networks) and / or transducers.

The components shown in FIG. 1 are typically arranged to optimize the surround sound effect to enhance and enhance the listening experience of the viewer 28. The viewer 28 is typically facing the television 12 and the television 12 is in the vicinity of the front center speaker 2.
It has 0. Therefore, the front center speaker 20 and the television 12 output audio and video output to the viewer 2 respectively.
Emit toward 8. Left satellite speaker 22 is typically located to the left of viewer 28 and right satellite speaker 24 is located to the right of viewer 28. These two satellite speakers are typically located approximately in the center of viewer 28 and television 12. The rear environment speaker 26 is a speaker that contributes to creating a spacious sound effect, and is typically located after the viewer 28. Although the rear environment speaker 26 is depicted as a single speaker, the system of the present invention may have multiple rear environment speakers 26.

FIG. 2 shows an enlarged block diagram of a preferred embodiment of the present invention. This enlarged block diagram shows a partial circuit and wiring diagram, and is referred to as a block diagram, a circuit diagram, or a wiring diagram in this specification. The home theater surround sound speaker system 100 (sometimes referred to as a “surround sound system”) includes a left satellite speaker 102 (sometimes referred to as a “left side or satellite speaker”) and a right satellite speaker 104 (“right side or Satellite Speaker "
), The front center speaker 106,
It comprises a surround or rear speaker 108 and a subwoofer speaker 110. Left channel amplifier 112
Outputs the amplified left channel signal. This signal is input to the positive terminal of the voice coil 114a of the front center speaker 106. The negative terminal of the left channel amplifier 112 is connected to the negative terminal of the voice coil 114a of the front center speaker 106. Similarly, the right channel amplifier 116
Outputs the amplified right channel signal. This signal is input to the positive terminal of the voice coil 114b of the front center speaker 106. The negative terminal of the right channel amplifier 116 is connected to the negative terminal of the voice coil 114b of the front center speaker 106. Therefore, the left and right channel signals are divided into two voice coils 114a of the front center speaker 106,
114b is connected in the same phase (synchronously). Therefore, the output of the front center speaker 106 is the sum of the left and right channel signals (hereinafter, referred to as “L + R”).

From the positive terminal of the left channel amplifier 112, the amplified left channel signal is output to the positive terminal of the left speaker 102 via the filter 118. The negative terminal of the left channel amplifier 112 is connected to the negative terminal of the left speaker 102. Similarly, the right channel amplifier 11
From the positive terminal 6, the amplified right channel signal is output to the positive terminal of the right speaker 104 via the filter 120. The negative terminal of the right channel amplifier 116 is connected to the negative terminal of the right speaker 104. Therefore, in the embodiment of FIG. 2, the amplified left and right channel signals are output to the left and right speakers, respectively.

The left speaker 102 and the right speaker 104
Is preferably band limited to reproduce only high frequencies. This is, as shown, the left high-pass filter 1
18 and the right high-pass filter 120. A high-pass filter 1 is provided to each of the left and right speakers 102 and 104.
18 and 120, the left and right speakers 102, 1
04 can be limited to high frequencies. As described later in detail with reference to FIG. 4A and FIG.
ary frequencyrange) can be eliminated. Therefore, the viewer feels that the conversation sound comes only from the front speaker 20 located near the video image. An example of such a high-pass filter will be described later in detail with reference to FIGS. 4A and 4B.

Surround sound speaker system 10
0 also has a rear speaker 108. Rear speaker 1
Input to 08 produces a left-right difference signal (LR). To provide this difference signal, the positive terminal of left channel amplifier 112 outputs the amplified left channel signal to the positive terminal of rear speaker 108, and the positive terminal of right channel amplifier 116 outputs the amplified right channel signal to the rear speaker. 108 is output to the negative terminal. By making the connection to the rear speaker 108 as described above, a desired (LR) difference signal is obtained. The rear speaker 108 also has a potentiometer 109. By potentiometer 109,
The acoustic output of the rear speakers can be adjusted relative to the output of the other speakers in the system. Such output is typically adjusted based on how close the rear speakers are to the viewer. One skilled in the art will appreciate that reversing the polarity of the connection to the rear speaker 108 will result in an (RL) difference signal instead of an (LR) difference signal. Since the polarity of the difference signal radiated from the rear speakers does not significantly affect the performance of the surround sound speaker system 100, either one may be selected.

Surround sound speaker system 10
0 also has a subwoofer 110. The positive terminal of the left channel amplifier 112 outputs the amplified left channel signal to the positive terminal of the left subwoofer speaker 122. The negative terminal of the left channel amplifier 112 is connected to the negative terminal of the left subwoofer speaker 122. Similarly, the positive terminal of the right channel amplifier 116 outputs the amplified right channel signal to the positive terminal of the right subwoofer speaker 124. The negative terminal of the right channel amplifier 116 is connected to the negative terminal of the right subwoofer speaker 124. Therefore,
In the embodiment of FIG. 2, the left channel signal drives the left subwoofer speaker 122 and the right channel signal drives the right subwoofer speaker 124. Therefore, the outputs from the left and right subwoofer speakers are acoustically summed.
One of ordinary skill in the art will appreciate that the center channel speaker 108 may alternatively be used to operate over the entire frequency range (including the bass range), thereby eliminating the need for a subwoofer. .

In a variation of the preferred embodiment, the left and right amplifiers 112, 116 are integrated into the system. For example, the left and right channel amplifiers 112, 1
Although 16 is generally considered to be the output amplifier commonly used for the audio signal source throughout this specification, it is understood that any amplifier specifically selected to form part of the surround sound system 100 may be used. Good. The amplifiers 112 and 116 of this modification receive a low-level input signal from an audio signal source. Amplifier 1
Reference numerals 12 and 116 further amplify the input signal and output it to the surround sound speaker system. For such a configuration, the output amplifiers 112, 116 may be incorporated into the interconnect module 14 (FIG. 1). The interconnect module 14 is preferably powered independently and the amplifier 11
2, 116 are driven. A great advantage of this variant is that the output amplifiers 112, 116 can be designed to match the electrodynamic characteristics of the loudspeaker.

One preferred embodiment of the surround sound system 100 has a front center speaker 106. The front center speaker 106 has a sealed enclosure of about 50 cubic inches.
losure), in which a commercially available diameter of 3
Inch (7.62 cm) dual 8 ohm voice coil dynamic transducer
rodynamic transducer). A pair of 100
Microfarad capacitors are connected in series to the respective positive outputs of the left and right channel signals, thereby performing a crossover function. Front center speaker 106 is about 150
It has an operating bandwidth higher than Hz. Rear speaker 108
Has a similar structure, but uses a single voice coil transducer instead of a dual voice coil transducer. The rear speaker 108 comprises a sealed enclosure of approximately 50 cubic inches and contains a commercially available 3 inch diameter single 8 ohm voice coil dynamic transducer. Potentiometer 109 is an 8 ohm 15 watt L pad or a 25 ohm 3 watt wound potentiometer. The rear speaker 1 is controlled by the potentiometer 109.
08 output level can be varied. A 68 microfarad capacitor is connected in series with the input to the positive terminal of the voice coil, which performs the crossover function. The nominal frequency band of the rear speaker 108 is 150 Hz to 8
KHz. The rear speaker 108 reproduces the (LR) difference signal as described with reference to FIG. Each of the side speakers 102, 104 is about 2 cubic inches (about 33 cubic inches).
It consists of a cubic centimeter sealed enclosure containing a commercially available nominally 4 ohm impedance plastic cone tweeter 1.5 inches in diameter. A pair of 4.7 microfarad capacitors are connected in series with the positive inputs to side speakers 102, 104, which provide high pass filtering for left high pass filter 118 and right high pass filter 120. With these high-pass filters 118 and 120, the output from the side speakers 102 and 104 is approximately 4 kHz to 15 kHz.
It has a nominal frequency band of z. The subwoofer 110 has a conventional two-part enclosure structure, which has a nominal 580 cubic inch (about 9504 cubic centimeter) hermetic section and a pair of 5.25 inch (13.
Nominal 450 cubic inches (737) working with a 34 ohm (4 cm) 4 ohm voice coil dynamic transducer.
4 cubic centimeters) with a port. A pair of 0.8 millihenry inductors are connected in series with the positive input to each transducer to perform a crossover function. Subwoofer bus unit 110 is nominally 50H
It operates in the frequency band from z to 200 Hz. In each of the loudspeakers, the crossover network is integrated into the associated loudspeaker enclosure.
Further, band limiting (band limiting) filters 118 and 12
0 is integrated with the speakers 102 and 104, respectively. Thus, the band limiting device and its associated satellite speakers form an integral unit. This has the further advantage that the interconnect module 14 of FIG. 1 can simply consist of appropriately wired input and output jacks.

FIG. 3A shows a second preferred embodiment of the present invention. The home theater surround sound speaker system (also referred to as a “surround sound system”) 200 of FIG. 3A includes components similar to those of the surround sound system 100 of FIG. Was attached. The surround sound system 200 of FIG. 3A is substantially the same as that shown in FIG. 2, except that the left side speaker 202 and the right side speaker 204 have difference signals (LR) and (R-
L). The positive terminal of the left channel amplifier 212 supplies the amplified left channel signal via the filter 218 to the left side speaker 20.
2 to the positive terminal. The positive terminal of the right channel amplifier 216 outputs the amplified right channel signal to the negative terminal of the left side speaker 202. Similarly, the positive terminal of the right channel amplifier 216 outputs the amplified right channel signal to the positive terminal of the right side speaker 204 via the filter 220. The positive terminal of the left channel amplifier 212 outputs the amplified left channel signal to the negative terminal of the right side speaker 204. By making such a connection, (L
-R) The difference signal is input to the left side speaker 202,
The (RL) difference signal is input to the right side speaker 204.

As described with reference to FIG. 1, the left high-pass filter 218 and the right high-pass filter 220 eliminate and remove low-frequency components of the input signals to the left side speaker 202 and the right side speaker 204, respectively. If the satellite speaker receives the difference signal as an input, it is optional (or not) to provide the high-pass filter for the difference signal shown in FIG. However, (L
-R) High-pass filtering the difference signal has two advantages. First, the physical size of the side speakers can be kept small. Second, even if the speech leaks to the difference signal due to a mismatch between the left and right channel signal gains, band limiting the difference signal will eliminate this leak signal in the main voice frequency range, thus reducing the concentration of speech. Center speaker. This is true even if the left and right channel signals are not exactly equal and the conversation leaks into the difference signal.

In a modification of the second preferred embodiment, when the polarity of the difference signal is inverted, the (LR) difference signal is supplied to the right side speaker 204 and the (RL) difference signal is supplied. The signal is supplied to the left side speaker 202. In another modified example, the (LR) difference signal is
2, 204, or the (RL) difference signal can be supplied to both side speakers 202, 204. If the difference signal is band limited, the particular polarity of the difference signal provided to the side speakers will not significantly affect the performance of the system. This is because the side speakers operate at a nominal frequency of about 1 KHz or more (a range in which no acoustic difference can be heard). In addition, since the sound signal wavelength in this frequency range is relatively short, with respect to signal synthesis at the listening position, a small change in the relative position between the side speakers 202 and 204 indicates that the signal supplied to both side speakers The effect is greater than the relative polarity.

The great advantage of driving the left side speaker 202 and the right side speaker 204 with a difference signal ((LR) or (RL)) is that the difference signal is a sound component recorded equally on the left and right channels. And effectively separate the conversation and the reproduction of environmental surround sound. Given a system where the left and right channel signals are each output to the left and right side satellite speakers, the remaining vocal energy harmonics (harmonics) will remain in the left and right signals at higher frequencies (eg, harmonics) and sibilance Sounds as. When such sibilance is reproduced by a satellite speaker, the satellite speaker emits a directional cue, which results in unnatural breathing and breathing during a conversation, harming the acoustic image. However, difference signals can solve these problems by eliminating speech energy from environmental surround sound without a trace. Another advantage is obtained by band limiting the difference signal, which contains substantially only environmental surround sound information. That is, by limiting the band of the difference signal, a smaller satellite speaker can be used. This is because satellite speakers need only reproduce high frequency sound output. Therefore, by limiting and using the difference signal, it is possible to separate conversation and reproduction of environmental sound. This allows the conversation to focus on the video image while maintaining a consistent environmental sound field. The above separation creates a fundamental difference between the passive system of the present invention and the active surround sound decoding system. The passive system of the present invention does not create any artificial sound as the conversation enters or leaves the ambient sound field recorded on the surround track. Thus, a consistent environmental sound field can be formed while keeping the conversation focused on the video screen. The connection of the front center speaker, subwoofer, and rear speaker in FIG. 3A is the same as that described in FIG. The left channel amplifier 212 outputs the amplified left channel signal, and this signal is input to the positive terminal of the voice coil 214a of the front center speaker 206. The negative terminal of the voice coil 214 a of the front center speaker 206 is connected to the negative terminal of the left channel amplifier 212. Similarly, the right channel amplifier 216 outputs the amplified right channel signal, and this signal is input to the positive terminal of the voice coil 214b of the front center speaker 206. Front center speaker 2
The negative terminal of the voice coil 214 b is connected to the negative terminal of the right channel amplifier 216. Therefore, the left and right channel signals are input to the two voice coils 214a and 214b of the front center speaker 206 in the same phase, and
The output of the front center speaker 206 is a left and right total signal.

Referring again to FIG. 2A (and FIG. 3). Left side speaker 102 (202) and right side speaker 10
4 (204) are the left and right channel amplifiers 112 (21
2) and 116 (216) to receive the amplified signals respectively. However, the side speakers 102 (20
2) The operating bandwidth of 104 (204) is limited. The side speaker 102 (202) in the present invention,
The bandwidth of 104 (204) is
It is limited to a frequency range substantially above the main frequency range of the speech or voice signal output from (206). More specifically, the main energy of the speech signal is about 1
It is included in the frequency range of 50 Hz to 1 KHz.
Then, the side speakers 102 (202) and 104 (2
04) are high-pass filters 118 (21
8) Bandwidth limited by 120 (220) and operates in a frequency range of at least about 1 KHz or higher.

FIG. 3B shows a modification of the second preferred embodiment of the present invention. The home theater surround sound speaker system (also referred to as a "surround sound system") 200 'of FIG.
A includes components similar to those of the A surround sound systems 100 and 200, and these similar components are denoted by the same reference numerals. 3B surround sound system 20
0 ′ is substantially the same as that shown in FIG. 3A, except that the left side speaker 202 and the right side speaker 204 are configured to produce difference signals (L-βR) and (R-βL), respectively. Different. As shown in FIG. 3A, the positive terminal of the left channel amplifier 212 supplies the amplified left channel signal to the left side speaker 20 via the filter 218.
2 to the positive terminal. The positive terminal of the right channel amplifier 216 outputs the amplified right channel signal to the negative terminal of the left side speaker 202 via the attenuator 270. Similarly, the positive terminal of the right channel amplifier 216 outputs the amplified right channel signal to the positive terminal of the right side speaker 204 via the filter 220. Left channel amplifier 2
The positive terminal of 12 attenuates the amplified left channel signal to attenuator 2
The signal is output to the negative terminal of the right side speaker 204 via 72.

The attenuators 270 and 272 reduce the drawn signal before it is input to the negative terminals of the side speakers 202 and 204, respectively. Therefore, the difference signal (L-βR) is output from the left side speaker 202, and the difference signal (R-βL) is output from the right side speaker 204.
Here, β is the gain of each of the attenuators 270 and 272. The gain β of the attenuators 270, 272 preferably has a value between 0 and 1. As will be understood by those skilled in the art, the gain β of the attenuators 270 and 272 may be a fixed value or a variable. Whether to use a variable or a fixed value depends on the application example. Further, each attenuator 270,
272 may have different gains. In this case, attenuator 270 has gain β ₁ and attenuator 272 has gain β
_{With 2} . As those skilled in the art will readily recognize,
Various types of attenuators 270 and 272 having (providing) the gain β can be considered. For example, in the case of a relatively small configuration, resistors or potentiometers may be used as the amplifiers 270 and 272. In more complex configurations, attenuators 270, 272 may utilize any of a number of amplifiers known to those skilled in the art.

FIG. 4A shows the left side speaker 102 (202) and the right side speaker 104 (204) of FIGS.
1 shows a pair of first-order high-pass networks for performing high-pass filtering on an input signal to a first network. Left high-pass filter 118 (218) and right high-pass filter 1
20 (220) has capacitors 150 and 152, respectively, and these capacitors 150 and 152 are connected in series to the side speakers 102 (202) and 104 (204), respectively. Such a filtering structure is called the first
It is called a secondary high-pass filter. FIG. 4B shows a left high-pass filter 11 provided as a second-order high-pass network.
8 (218) and right high-pass filter 120 (220). Capacitors 154 and 156 are connected in series to the positive terminals of side speakers 102 (202) and 104 (204), respectively, and inductors 158 and 160 are connected between the positive and negative terminals of side speakers 102 (202) and 104 (204) ( Are connected in parallel. The operation of the high-pass network shown in FIGS. 4A and 4B should be well understood by those skilled in the art and will not be described here.

Those skilled in the art will appreciate that high pass filter 118
It will be appreciated that (218), 120 (220) may be any of a number of known in the art. It will be readily apparent that the use of a passive high pass filter is one approach to band limiting the signal. Those skilled in the art will also recognize that the cutoff frequency will vary depending on the application.

Side speakers 102 (202), 104
By limiting the bandwidth of the frequency range of the input signal to (204), the side speakers 102 (202), 10
4 (204): Conversation concentration signal (dialog localizat)
ion cues) can be substantially eliminated, so that the main speech intensive signal is reproduced only by the front center speaker 106 (206), which is close to the video image. By limiting the bandwidth of the side speakers 102 (202) and 104 (204), conversation is concentrated on the position of the front center speaker 106. This is because, of the speakers of the present system, only the center channel serves as a speaker for reproducing a basic conversation concentration signal. Left side speaker 102 (202) and right side speaker 104 (204)
Reproduces the high frequency information of each of the left and right channels, which is typically higher than the frequency range of the primary speech. Therefore, the side speakers 102 (202), 104
(204) helps to enhance the spaciousness without changing the concentration of the speech sound. Numerous studies of concert hall acoustics have shown that there is a correlation between creating a spacious feel and the presence of side reflections. That is, there is a correlation between the feeling of being spacious and the energy reaching the listening position from the side of the listening space. Side speakers 102 (202), 1
04 (204) is located at the side of the listening room, and when the main axis of radiation is directed vertically upward, the side speaker 102
(202), 104 (204) generate significant lateral (side) energy at the listening position. Therefore, a spacious feeling can be enhanced. Also, since the side speakers 102 (202) and 104 (204) of the present invention are band-limited and the conversation concentration signal is considerably reduced, they can be positioned further to the side of the viewer than conventional speakers. Further, the side speakers 102 (20
2) By limiting the band of 104 (204),
Moving far to the side does not detract from the sound image on the side of the viewer. If the full frequency range side speakers were placed in that position, the sound image on the side of the viewer would be corrupted. As a result, the side speakers can be arranged at positions where the spaciousness is maximized without generating and forming a distorted sound image.

Another advantage of band limiting the side speakers is that the physical size of the side speakers can be relatively small. Band limiting the side speakers above about 1 KHz can be very different from a typical satellite / subwoofer system. In most satellite / subwoofer systems, satellite speakers have a fairly large frequency range (typically 1).
Up to frequencies as low as 50 Hz fall within that range). Therefore, such speakers are much larger than the side speakers of the present invention to generate sufficient energy at low frequencies. In the present invention, the side speakers play in a fairly limited frequency range.

FIG. 5A shows the dual voice coils 114a, 114b (214a, 214) shown in FIGS.
b) and a front central speaker 106 (206) consisting of a single transducer 115 (215). The amplified left channel signal is transmitted to the voice coil 114
a (214a) and the amplified right channel signal is supplied to the voice coil 114b (214b).
In this configuration, the left and right channel signals are electromagnetically summed in the transducer 115 (215).

Another notable advantage of the present invention is that
A can be obtained with the configuration of A. In FIG. 5A, the amplifier 11
2 and 116 respectively output the left and right channel signals of the voice coil 1 of the transducer 115 individually.
14a and 114b, and electromagnetically generates a (L + R) sum signal. Thus, the front center speaker of FIG. 5A passively generates a sum signal. In this case, there is no need for a register divider network that consumes power, increases system cost, and complicates the system. Such power savings are particularly noteworthy when the present invention derives the left and right channel signals from a relatively low power (output) amplifier source (eg, a typical stereo television or a boombox portable stereo). is there. The left + right summation within the speaker itself eliminates the need for extra (separate) parts and associated costs.

In the alternative center channel configuration shown in FIG. 5B, the left and right channel signals drive individual (independent) left and right transducers 117, 119. The amplified signal of the left channel is transmitted to the voice coil 114a (214
a) to drive the left transducer 117
Is driven. The amplified signal of the right channel drives the voice coil 114b (214b), which drives the transducer 119.

In the configuration shown in FIG. 5B, the transducer 11
7 and 119 must be located relatively close. This is to acoustically sum the output from both transducers 117, 119 in the largest possible frequency range. For effective acoustic summing, the two transducers must be located within about one-quarter of each other's wavelength. Such close proximity cannot be practically performed in the entire audio frequency range. At higher frequencies, some comb filtering is applied to the combined acoustic output from the two transducers.
g) results. In the case of a monaural signal, because the two transducers emit the same signal and are spatially separated, the difference in path length between the listening position and each transducer will, at high frequencies, be a large fraction of the wavelength or It becomes several times the wavelength. Thus, minimizing the distance between the two components minimizes the amount of comb filtering that occurs.

FIG. 6 shows the rear speaker 10 of FIGS.
8 shows two modified embodiments for obtaining the (LR) difference signal from (208). The difference signal typically contains environmental and surround sound information. FIG. 6A shows a circuit diagram according to a preferred embodiment for obtaining the (LR) difference signal in a passive system. The left channel amplifier 112 (212) outputs the amplified left channel signal, which is input to the positive terminal of the voice coil 130 of the rear speaker 108 (208). Right channel amplifier 1
16 (216) outputs the amplified right channel signal to the negative terminal of the voice coil 130. Therefore, the rear speaker 10
8 (208) outputs a sound corresponding to the difference (LR) between the left and right channel signals via the transducer 134. FIG. 6B shows a circuit diagram according to another configuration for obtaining the (LR) difference signal. The rear speaker 108 has dual voice coils 132a, 132b. The voice coil 132a has a positive terminal connected to the left channel amplifier 11
2 (212).
The negative terminal of the voice coil 132a is the left channel amplifier 1
12 (212). The voice coil 132b has a negative terminal connected to the right channel amplifier 116.
Receive the amplified right channel signal from (216). The positive terminal of the voice coil 132b is the right channel amplifier 11
6 (216). Therefore, in this configuration, the polarity of the connection / coupling is inverted, and the transducer 134 outputs an (LR) signal.

FIG. 7 shows a third preferred embodiment of the present invention. This home theater surround sound speaker system 300 performs low-level signal processing before amplification by the amplifiers 302 and 304. The left channel positive signal 306 and the right channel positive signal 308 are provided to an addition amplifier 310 (which may be any of the addition amplifiers known in the art for electronically adding the above signals). The output of the addition amplifier 310 is a (L + R) sum signal, which is input to the power amplifier 302. Amplifier 3
The positive output of 02 is an amplified (L + R) signal, which is input to the positive terminal of the center speaker 312. Central speaker 3
The negative terminal of 12 is connected to the negative terminal of the amplifier 302.

The positive terminal of the power amplifier 302 outputs a drive signal to the positive terminal of the subwoofer 314. The subwoofer 314 includes a single transducer and a voice coil. Like the center speaker 312, the (L + R) signal drives the subwoofer 314, so that the subwoofer 3
14 is to output the low frequency parts of the left and right signals,
Only a single voice coil and transducer are required. Those skilled in the art will appreciate that subwoofers of other configurations can be used in the present invention with little effect on the operation of the system.

Surround sound speaker system 30
0 also actively generates a difference signal. Prior to amplification by amplifier 304, left channel positive signal 306 and right channel positive signal 308 are provided to subtraction amplifier 316.
From the output terminal of the subtraction amplifier 316, left-right (LR)
A difference signal is output. This (LR) difference signal is input to the power amplifier 304. And the power amplifier 304
Drive 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. Therefore, the (LR) difference signal output from the amplifier 304 drives the rear speaker 318.

A drive signal is output from the positive terminal of the power amplifier 304 to the positive terminal of the left side speaker 320 via the high-pass filter 324. Left side speaker 32
The negative terminal of 0 is connected to the negative terminal of the power amplifier 304. Similarly, a drive signal is output from the positive terminal of the power amplifier 304 to the negative terminal of the right side speaker 322 via the high-pass filter 326. Right side speaker 32
The second positive terminal is connected to the negative terminal of the power amplifier 304. By the connection to the left side speaker 320 as described above, the (LR) drive signal is supplied to the speaker. Further, by the connection to the right side speaker 322 as described above, the (RL) signal is supplied to the speaker. The polarity of the signal supplied to each of the left side speaker 320, the right side speaker 322, and the rear speaker 318 may be reversed, and the operation and effect of the present system do not change even in this case. The relative polarities of the difference signals to the two side speakers and the rear speaker may be replaced in any manner,
In addition, the operation and effect of the present system are not changed. The high pass filters 324, 326 operate in the same manner as described with reference to FIGS.

Such a configuration is particularly suitable for high power applications and high power applications (powered variations). That is, it is suitable for an application example in which the interconnection module has an internal amplifier, amplifies an electric input signal by the internal amplifier, and outputs the amplified electric signal to drive each speaker. A particular advantage of the internally powered interconnect module is that the output signal is asynchronous so that speakers that require more energy to operate properly can receive higher power input signals. It gives you the option to amplify the situation. For example, the sum signal input to the center and bass speakers may be output at a significantly higher power level than the difference signal output to the satellite and rear environment speakers. This can provide high power to drive the bass and front speakers, while leaving low power sufficient to drive the side and rear speakers. For example, instead of a 10 watt + 10 watt stereo amplifier configuration, an 18 watt + 2 watt amplifier configuration can be used to more effectively utilize the power that is normally available.

FIG. 8 shows a fourth preferred embodiment of the present invention. The home theater surround sound speaker system 400 (hereinafter sometimes referred to as a “surround sound system”) 400 in FIG. 8 includes components similar to those of the surround sound system 100 in FIG. Signed. The surround sound system 400 shown in FIG. 8 has substantially the same structure as the system shown in FIG. 2, except that it receives and outputs a monaural signal instead of the left and right channel signals which are components of a stereo signal. The surround sound system 400 includes a left side satellite speaker 402 (sometimes referred to as “left side speaker or left satellite speaker”) and a right side satellite speaker 404 (sometimes referred to as “right side speaker or right satellite speaker”).
, Front center speaker 406, surround or rear speaker 408, and subwoofer speaker 410. Amplifier 412 receives the monaural signal and outputs an amplified monaural signal. This amplified monaural signal is input to the positive terminal of the voice coil 414 of the front center speaker 406. Voice coil 414 of front center speaker 406
Is connected to the negative terminal of the amplifier 412. Voice coil 414 of front center speaker 406 drives transducer 415 to cause front center speaker 406 to output sound. The positive terminal of the amplifier 412 is the filter 4
The amplified signal is output to the positive terminal of the left side speaker 402 via the output terminal 18 and the amplified signal is also output to the positive terminal of the right side speaker 404 via the filter 420. As shown, using the left high-pass filter 418 and the right high-pass filter 420, the left side speaker 402 and the right side speaker 402 are band-limited and reproduce only high frequencies. The operation of the left high-pass filter 418 and the right high-pass filter 420 are as described above.

The surround sound system 400 also has a rear speaker 408. This rear speaker 408
Receives the amplified output from the amplifier 412. The rear speaker 408 has a potentiometer 409, thereby forming a ground line for an amplified signal input to the rear speaker 408. The potentiometer 409 allows the acoustic output of the rear speaker 408 to be adjusted with respect to the output of other speakers in the system. Rear speaker 408 is preferably adjusted such that the sound pressure level generated at the viewer's location by rear speaker 408 is less than the sound pressure level generated by front speaker 415 at that location. In this way, the viewer perceives the conversation from the front stage based on the order, priority, and precedence effect of sound reproduction. That is, if two similar sounds are emitted, the human listening process / hearing will interpret the direction of one of the sounds that arrived first as the direction in which the two sounds were emitted. Time-intenance exchange
psychoacoustic phenomenon known as sity trading)
Viewers perceive that higher-level sound arrives first. Thus, by changing the output from the rear speaker 408 to a level sufficiently lower than the output of the front speaker 406, the acoustic image appears to be in front, but
The acoustic energy from the rear speakers 408 provides additional acoustic information. The listening process / hearing perceives this additional information as environment or surround sound. One skilled in the art will appreciate that the level adjustment can be performed by any of a number of known techniques. Also, since the embodiment of FIG. 8 uses only one channel of amplification, the viewer is typically required to obtain the desired sound pressure level compared to the stereo type using two channels. Increase volume.

As a modification of the fourth embodiment shown in FIG. 8, a similar operation is obtained when a monaural signal is supplied to the amplifier 212 without supplying an input signal to the positive input of the amplifier 216 in the configuration of FIG. 3A. The effect is obtained. In this modification as well, a surround sound effect can be obtained based on a monaural input signal, so that the surround sound system shown in FIG. 3A can be used for both a stereo signal and a monaural signal. That is, the application range of the system of FIG. 3A can be expanded.

A particularly desirable feature of most surround sound systems is that they are easy to install and operate. This is to prevent an amateur user from hesitating to purchase and use it. The present invention solves most installation difficulties by providing a connection jack on the interconnect module 14 for the home theater. By providing a connection jack, (LR)
In configurations where the difference signal is output to side speakers, the surround sound system has only one or a set of speaker connections. FIG. 9 is a wiring diagram showing an interconnecting jack in the interconnecting module 14 of FIG.
Description will be given based on the components described in FIG.

The interconnection module 14 has a four-terminal input jack 30 for receiving left and right channel signals (component signals) input from the television 12 to the interconnection module 14. The left and right channel signals are received via four conductors extending to a four terminal connector appropriately connected to the four terminal input jack 30. The negative inputs of the left and right channels are tied in interconnect module 14 and are used as a common ground signal for each of the input and output connections. Output to the front center speaker 20 (FIG. 1) is provided via a three terminal output jack 32. The three terminals of the three-terminal output jack 32 provide an output consisting of a left channel signal, a right channel signal, and a common ground signal. Second
The three-terminal subwoofer output jack 34 supplies a similar output signal to the subwoofer 18. Similarly, the subwoofer output jack 34 supplies a left channel signal, a right channel signal, and a common ground signal to respective terminals.

Three two-terminal output jacks 36a, 36
b and 36c supply the left channel signal to one terminal and the right channel signal to the other terminal. Each of these jacks is connected to a cable connected to one of the rear speaker 26, the left satellite speaker 22, and the right satellite speaker 24. The signals supplied to these speakers are left-right difference signals. Therefore, the configuration of the interconnection module 14 includes a left satellite speaker 22, a right satellite speaker 24, and a rear speaker 26.
Are particularly suitable for the preferred embodiment shown in FIG. 3A, which receives the difference signal as input. Those skilled in the art will appreciate that the output jacks 36a, 36b, 36c are interchangeable. This is because each jack outputs a substantially identical signal.

One of the outstanding features of the interconnect module 14
First, the front center speaker output jack 32 and the subwoofer output jack 34 may be the same jack that outputs the same signal to each terminal. Thus, during installation, the operator can assemble the system in only one way. The operator is the front center speaker 2
A zero or cable connector (not shown) for the rear speaker 26 cannot be connected to one of the output jacks 36a, 36b, 36c. Similarly, output jack 36
a, 36b and 36c supply the same signal to each terminal.
That is, all similarly configured output (and input) jacks provide (receive) the same signal. Similarly, an operator cannot connect a cable connector for a satellite or rear speaker to the front center speaker output jack 32 or the subwoofer output jack 34.
An operator can only connect a cable connector to one of a plurality of jacks that output signals appropriate for a particular speaker. In addition, by the action of the present invention,
The configuration and assembly of the interconnection module 14 are facilitated, and mounting is facilitated. Another advantageous feature of the present invention is that the interconnect module 14 is particularly adapted for standard two, three and four core cables which facilitate (enable) low cost manufacturing. This is because these components are readily available.

[0092] Improvements in any home theater surround sound speaker system can be achieved by reducing the number of parts. One way to reduce the number of parts is to consolidate the parts where possible.
For example, referring to FIG. 1, the interconnect module 14 and the subwoofer 18 can be theoretically integrated into one component. FIG. 10 shows a configuration (modification) in which the components of the home theater surround sound speaker system 10 of FIG. 1 are arranged and integrated as described above. The home theater surround sound speaker system (also referred to as "surround sound system") 10 'in FIG.
Is almost the same as that of FIG. 1, and similar components are denoted by the same reference numerals. As shown in FIG. 10, the television 12 outputs audio signals to an integrated interconnect module and subwoofer bass speaker (integrated bus unit) 40. The integrated bus unit 40 performs the functions of both the interconnect module 14 and the subwoofer 18 of FIG. The interconnection module 14 is housed and housed in the housing of the subwoofer bass speaker, reducing the number of parts and wiring, thereby facilitating assembly. The integrated bus unit 40 includes the front center speaker 2
0, left satellite speaker 22, right satellite speaker 24, and rear environment speaker 26 each have an interconnect that distributes appropriate signals. The integrated bus unit 40 also has a subwoofer wired directly to an interconnect circuit housed in the integrated bus unit 40. Thus, the system has one less cable (no cable between the interconnect module and the subwoofer bass speaker). Also, the number of independent components is one less (the interconnection module is not provided in a separate and independent form).

FIG. 11 is a perspective view of an example of the integrated bus unit 40. The integrated bus unit 40 includes an interconnect module 42 having input and output jacks. The input and output jacks receive the incoming audio signal and distribute the left, right and difference signals to the appropriate speakers. The interconnect module 42 has a four terminal input jack 44 for receiving left and right channel signals via four conductors. Interconnect module 42
Also has one three-terminal central speaker output jack 46
And three two-terminal output jacks 48a, 48b, 48c
Having. This interconnect module 42 has substantially the same configuration as the interconnect module 14 of FIG. 9, and the principles described in FIG. 9 are equally applicable to that of FIG.

One major difference between the interconnect module 42 of FIG. 12 and the interconnect module 14 of FIG. 9 is that the interconnect module 42 is integrally housed in a subwoofer bass speaker so that the interconnect module 42 is It does not require an output jack (the interconnect module 14 of FIG. 9 does). The left channel signal, the right channel signal, and the common ground signal are provided directly to the crossover network of the integrated subwoofer unit 40.

Another advantage of another variant of the present invention is the common problem of many typical consumer audiovisual rooms (easy wiring of interconnect modules to satellite speakers and rear environmental speakers). Things impossible)
Is resolved. Typically, in the wiring connection of a home theater surround sound system, cables should be provided along the side and rear walls of the room, or holes should be drilled under the floor or under the floor to place the cable under the floor. Then, it is necessary to pull up the cable again from under the floor into the room at the position of each speaker.

As shown in FIG. 13, the present invention is particularly suitable for a wireless home theater surround sound speaker communication system 50. Television (TV) 51
Supplies the left and right channels of the stereo audio signal to the interconnect module 52. Interconnect module 52
Constructs a desired system by supplying left and right channel signals to appropriate speakers. FIG.
In the embodiment shown in FIG. 5, the interconnect module 52 comprises a television 51, a front center speaker 54 and a subwoofer 70.
It is wired directly to. To transmit audio signals to the appropriate speakers, interconnect module 52 includes a transmitter 56 that transmits the audio signals to left satellite speaker 64, right satellite speaker 66, and rear environment speaker 68. The above speakers 64, 66, 6
Each of the 8 has a receiver 56 ′ that receives an output signal wirelessly provided by the transmitter 56 of the interconnect module 52. The receiver 56 'receives the supplied signal and converts the signal into an audio signal suitable for the speaker. Those skilled in the art will appreciate that receiver 56 'may be configured to output the converted signal to an amplifier before supplying it to the speaker.

[0097] Transmitter 56 and receiver 56 'preferably operate on one channel. To use a one-channel transmitter / receiver structure, the interconnect module 52 preferably outputs only one audio signal to each speaker. In such a desirable configuration, the home theater surround sound speaker system 300 of FIG. 7 is a preferred embodiment for implementing the wireless surround sound system 50 of FIG. In such an embodiment, the interconnect module 52 performs active signal addition and subtraction (as described in FIG. 7) to generate difference and sum signals prior to transmission to the respective speakers. According to this configuration, the wireless system can be limited to one-channel communication instead of multi-channel communication. Further, those skilled in the art will recognize that the left satellite speaker 320, the right satellite speaker 32
It is understood that the interconnect module 52 can use one transmitter (e.g., the transmitter at 56) to provide a drive audio signal to each speaker since the second and rear speakers 318 can be driven by substantially the same difference signal. I can do it. This allows a considerable cost reduction. Also, those skilled in the art will appreciate that similarly configured receivers and transmitters can be used to connect the speakers wirelessly in a manner similar to the wired connection described above.

From the above description, it is understood that the present invention can solve some problems of the prior art and can achieve the object of the present invention. Therefore, the present invention can provide a home theater surround sound system that is effective (efficient and efficient), low-cost, and easy to install. The front, rear, left, right, and bass speakers provide the desired sound output in response to providing the appropriate sum and difference signals created by combining the left and right channel signals of the stereo signal. The sum and difference signals cause the desired speech and environmental sounds to be output from the appropriate speakers.

Although the invention has been described above with reference to certain preferred embodiments, modifications and improvements can be made within the spirit and scope of the appended claims.

[Brief description of the drawings]

FIG. 1 is a block diagram of a home theater surround sound speaker system arranged in accordance with the principles of the present invention.

FIG. 2 is an enlarged block diagram of a first preferred embodiment of the home theater surround sound speaker system of FIG. 1;

FIG. 3A is an enlarged block diagram of a second preferred embodiment of the home theater surround sound speaker system of FIG. 1, showing a case where a difference signal is output to left and right satellite speakers.

FIG. 3B is an enlarged block diagram of a variation of the second preferred embodiment of the home theater surround sound speaker system of FIG. 1, wherein the signal subtracted to create the difference signal is attenuated prior to subtraction. ) Shows the case.

FIG. 4A is a circuit diagram of a first-order high-pass filter for limiting the bandwidth of input signals to left and right satellite speakers.

FIG. 4B is a circuit diagram of a second-order high-pass filter for bandwidth-limiting input signals to left and right satellite speakers.

FIG. 5A is a circuit diagram for providing a left + right sum signal (L + R) to a front center speaker using a single transducer structure.

FIG. 5B is a circuit diagram for providing a left + right sum signal (L + R) to the front center speaker using a dual transducer structure.

FIG. 6A is a circuit diagram for providing a left-right difference signal (LR) to a rear speaker of a home theater surround sound speaker system using a single voice coil structure and a dual voice coil structure.

FIG. 6B is a circuit diagram for providing a left-right difference signal (LR) to a rear speaker of a home theater surround sound speaker system using a single voice coil structure and a dual voice coil structure.

FIG. 7 is an enlarged block diagram of a third preferred embodiment of a home theater surround sound speaker system, wherein the difference signal and the sum signal of the left and right channels are actively generated before being output to the speaker. Is shown.

FIG. 8 is an enlarged block diagram of a fourth preferred embodiment of a home theater surround sound speaker system, showing a case where a monaural signal is output to each speaker.

FIG. 9 is a wiring diagram of an interconnect module for a home theater surround sound speaker system that is used to ensure that the system can be installed and operated.

FIG. 10 is a block diagram showing a modification of the home theater surround sound speaker system of FIG. 1;

FIG. 11 is a perspective view of an integrated subwoofer bus unit and an interconnection module (a perspective view of a configuration in which the subwoofer bus unit and the interconnection module are integrated).

FIG. 12 is a wiring diagram of an interconnect module integrated with a subwoofer bus unit for the system of FIG. 11, used to ensure installation and operation of a home theater surround sound speaker system.

FIG. 13 is a block diagram when the home theater surround sound speaker system is made wireless.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Home theater surround sound speaker system 12 Television 14 Interconnection module 18 Subwoofer 20 Front center speaker 22 Left satellite speaker 24 Right satellite speaker 26 Rear environment speaker 28 Viewer 40 Integrated bus unit 51 Television 52 Interconnection module 54 Front center Speaker 56 Transmitter 56 'Receiver 64 Left satellite speaker 66 Right satellite speaker 68 Rear environment speaker 70 Subwoofer 100 Home theater surround sound speaker system 102 Left satellite speaker 104 Right satellite speaker 106 Front center speaker 108 Rear speaker 110 Subwoofer speaker 122 Left subwoofer speaker 124 right subwoofer speaker 200 home sheer Ta surround sound speaker system 202 left side speaker 204 right side speaker 206 center speaker 208 rear speaker 300 home theater surround sound speaker system 306 left channel positive signal 308 right channel positive signal 312 center speaker 314 subwoofer 318 rear speaker 320 left side speaker 322 right Side speaker 400 Home theater surround sound speaker system 402 Left side satellite speaker 404 Right side satellite speaker 406 Center speaker 408 Rear speaker 410 Subwoofer speaker

────────────────────────────────────────────────── (5) Int.Cl. ⁶ Identification symbol FI H04S 5/02 H04S 5/02 PX G10K 15/00 M (71) Applicant 597111729 2757 44th Street, SW. , Suite 306, Grand Rapids, Michigan, United States of America (72) Inventor Halpie Greenberger Hopedale, Mass., USA Hopedale Laurelwood Drive 182 (72) Inventor William E. Tusac Lac, United States Gleasondale Road 459 (72) Inventor Jerome E. Roussica Stow Adams Drive, Massachusetts, USA 33

Claims (21)

[Claims] 1. A speaker system for reproducing a monaural audio signal generated by an audio signal source, comprising: a front speaker that outputs sound according to the monaural audio signal; A rear loudspeaker providing output; means for filtering the mono audio signal input to the left satellite loudspeaker to substantially eliminate low and mid-range acoustic frequencies; substantially responsive to only the filtered mono audio signal. A left satellite speaker that outputs an audio output through the filter; Sound output in response to A speaker system comprising: a right satellite speaker; and a bass speaker that outputs a low-frequency sound according to the monaural audio signal. 2. The speaker system according to claim 1, further comprising an amplifier that receives the monaural audio signal and amplifies the signal before supplying the signal to each speaker. 3. The speaker system according to claim 1, wherein the means for filtering the input to the left and right satellite speakers is substantially the same means, and further comprising a first-order filter. 4. The speaker system according to claim 1, wherein the means for filtering the inputs to the left and right satellite speakers are substantially the same means, and further comprising a secondary filter. 5. A left high-pass filter for passing an audio frequency of a monaural audio signal substantially higher than a predetermined threshold frequency to a left satellite speaker, and a monaural substantially higher than a predetermined threshold frequency to a right satellite speaker. The speaker system according to claim 1, further comprising: a right high-pass filter that passes an audio frequency of the audio signal. 6. The speaker system according to claim 5, wherein the left and right high-pass filters are substantially the same, and further comprising a capacitor connected in series to a positive input terminal of an audio signal supplied to the satellite speaker. 7. The right and left high-pass filters are substantially the same, and further include a capacitor connected in series to a positive terminal of each satellite speaker, and an inductor connected in parallel to the positive and negative terminals of each satellite speaker. Item 6. The speaker system according to Item 5. 8. A speaker system for reproducing a stereo audio signal generated by an audio signal source, comprising: a front speaker that outputs sound according to an (L + R) input signal; and a difference between left and right channel signals. A rear speaker that outputs an audio output in accordance with the determined input signal, and a variable difference signal ((L−β
R) or (R-βL)); means for filtering the variable difference signal input to the left satellite speaker to substantially eliminate low and mid-range acoustic frequencies; A left satellite speaker that outputs an audio output in response to only the difference signal; A speaker system comprising: a right satellite speaker that outputs sound according to only a difference signal; and a bass speaker that outputs low-frequency sound according to an (L + R) input signal. Here, L indicates the left channel signal of the stereo signal, R indicates the right channel signal of the stereo signal, and β indicates the gain factor of each signal. 9. The speaker system according to claim 8, further comprising at least one amplifier that receives and attenuates the left and right channel stereo audio signals obtained by subtracting the variable difference signal. Note that the amplifier gain β has a value that changes between 0 and 1. 10. The left satellite speaker (L-β)
R) or (R-βL), the right satellite speaker receives (L)
9. The speaker system according to claim 8, wherein the speaker system receives a variable difference signal determined by the other of -βR) and (R-βL). 11. The speaker system according to claim 8, wherein the means for filtering the input to the left and right satellite speakers are substantially the same means, and further comprising a first-order filter. 12. The speaker system according to claim 8, wherein the means for filtering the inputs to the left and right satellite speakers are substantially the same means, and further comprising a secondary filter. 13. The apparatus according to claim 1, further comprising: a left high-pass filter for filtering a variable difference signal input to the left satellite speaker; and a right high-pass filter for filtering a variable difference signal input to the right satellite speaker. 8. The speaker system according to 8. 14. The speaker system according to claim 8, wherein β changes between 0 and 1. 15. A speaker system for reproducing a stereo audio signal generated by an audio signal source and accompanied by a video signal, comprising: a sum signal (R + L) and a difference signal ((R−L) based on L and R input signals. β ₁ L) or (L-β ₂ R)), a signal reprocessor for generating and outputting, a first speaker for outputting an acoustic output according to the sum output signal, and a low-pass filter for filtering the difference output signal. And first means for substantially removing mid-range sound frequencies; a second speaker for outputting sound substantially in accordance with only the first filtered difference output signal; and filtering the difference output signal; Second means for substantially removing low and mid-range acoustic frequencies; a third speaker for producing an audio output substantially in response only to the second filtered difference output signal; Speaker system comprising a fourth speaker issuing sound output, in response to. Here, L indicates the left channel signal of the stereo signal, R indicates the right channel signal of the stereo signal, and β ₁ and β ₂ indicate the gains of the subtracted signals, respectively. 16. The speaker system according to claim 15, further comprising: a fifth speaker that outputs a low-frequency sound output in accordance with the sum output signal. 17. It has gains β ₁ and β ₂ respectively,
Receiving and amplifying the left and right channel input signals respectively,
_{2. The} method according to claim 1, further comprising: a pair of amplifiers for generating a difference signal by generating a β ₁ L signal and a β ₂ R signal before subtraction.
5. The speaker system according to 5. 18. The speaker system according to claim 15, wherein said β ₁ and β ₂ are equal. 19. The speaker system according to claim 18, wherein said β ₁ and β ₂ vary between 0 and 1. 20. The speaker system according to claim 15, wherein each of β ₁ and β ₂ changes independently. 21. The loudspeaker system according to claim 15, wherein said first and second filtering means are substantially the same means and further comprise a first-order filter.