Abstract:
A system reproducing surround phonic sound is simply constructed by a multichannel acoustic signal reproducing apparatus having at least a DVD reproducing section. A DVD, a CD, a radio or the like and speakers are provided integrally with the multichannel acoustic signal reproducing apparatus and the integral system is made movable. The acoustic signal reproducing apparatus is connected to a television receiver by an IEEE1394 interface or a USB interface. Speakers of the television receiver are used as main speakers and the speakers of a multichannel acoustic signal reproducing apparatus main body are used as sub-speakers such as rear speakers. The main speakers are controllable from the main body side.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a multichannel acoustic signal reproducing apparatus reproducing a DVD (Digital Versatile Dise or the like, and having sound field control means for obtaining surround phonic sound. 
     2. Description of the Related Art 
     There is known hitherto a DVD apparatus wherein multichannel acoustic signals are incorporated as a home Dolby sound system to obtain the presence and reality of sound. 
       FIG. 6A  is a conceptual view showing the arrangement of the speakers of a conventional DVD Dolby sound system (5-1 channel system). 
     In  FIG. 6A , reference symbol  1  denotes a sound field space,  2  denotes an audience,  3  denotes a recording and reproducing apparatus main body. As shown in  FIG. 6B , the recording and reproducing apparatus main body  3  has a television receiver (TV)  17  projecting a video signal onto a CRT  12 , a DVD recording and reproducing section  10  recording and reproducing a recording medium such as a DVD, a surround decoder  14  obtaining a surround sound field signal, a power amplifier  15  amplifying a signal outputted to each speaker for 5-1 channel Dolby sound, a controller  13  controlling the DVD recording and reproducing section  10  and the surround decoder  14 , and an MPEG (Moving Picture Experts Group) decoder  11  compressing a video signal from the DVD  10  and outputting the compressed video signal to the CRT  12 . The recording and reproducing apparatus main body  3  outputs a surround phonic sound signal to each of the surround system speakers through an output terminal  18 . 
     Reference symbol  4  denotes a speaker box containing a front left speaker (to be referred to as “FLS” hereinafter),  5  denotes a speaker box containing a front right speaker (to be referred to as “FRS” hereinafter),  6  denotes a center speaker (to be referred to as “CS” hereinafter),  7  denotes a woofer speaker without directivity,  8  denotes a speaker box containing a rear left speaker (to be referred to as “RLS” hereinafter), and  9  denotes a speaker box containing a rear right speaker (to be referred to as “RRS” hereinafter). The audience  2  is located to face the FLS, FRS and CS with the RLS and RRS arranged on rear left and right sides of the audience  2  and the WS arranged diagonally in the front left direction of the audience  2  so that the audience  2  can enjoy surround phonic sound. 
     As stated above, at least five speakers FLS, FRS, CS, RLS and RRS as well the WS are required to listen to surround phonic sound from the surround system speakers, and cables  16  connecting a main amplifier, a multichannel amplifier and the respective speaker with one another are scattered unseemly. 
     In addition, once a DVD player or the like is contained in a rack provided under the television receiver constituting the electronic equipment main body  3  and the DVD player or the like and the television receiver  17  are set up to be mutually connected, it is quite difficult and inconvenient to move them from a room in which the television receiver  17  and the DVD player or the like are set up, to another room. The same thing is true for a minicomponent or a high fidelity (hi-fi) audio system. That is, if the minicomponent or the hi-fi audio system is set on a desk or a dedicated rack, it is difficult to move it, making it impossible to effectively utilize the speakers. 
     The present invention has been made to solve the above-stated disadvantages. It is, therefore, an object of the present invention to provide a multichannel acoustic signal reproducing apparatus which can be freely moved from one room to another room, which can connect an electronic equipment main body to a plurality of speakers by one cable or wirelessly and which facilitates enjoying surround phonic sound. 
     SUMMARY OF THE INVENTION 
     The first invention is a multichannel acoustic signal reproducing apparatus of a movable type, capable of reproducing surround phonic sound and having at least three-dimensional speakers, characterized by comprising: output means for driving left and right main channel speakers. 
     The second invention is a multichannel acoustic signal reproducing apparatus characterized by comprising at least: a center speaker; left and right speakers separable from a housing; recording and reproducing means capable of recording and reproducing a recording medium; surround decoding means for decoding a multichannel acoustic signal from the recording and reproducing means to surround phonic sound; switching means for reproducing a predetermined number of channels of the multichannel acoustic signal through the center speaker and the left and right speakers, and switching and outputting remaining channels of the multichannel acoustic signal; and control means for controlling the recording and reproducing means, the surround decoding means and the switching means, and characterized in that channel signals of the remaining channels from the switching means are supplied to a target having speakers and capable of recording the channel signals, and reproduced as surround phonic sound through the control means, the target being a television receiver or an acoustic equipment. 
     The third invention is a multichannel acoustic signal reproducing apparatus according to the first or the second of the invention, characterized in that an output signal from the output means is transmitted to the target having the main speakers by a wire consisting of one wire or wirelessly; and the speakers of the multichannel acoustic signal reproducing apparatus are used as rear speakers. 
     According to the multichannel acoustic signal reproducing apparatus of the present invention, even after a home surround system is moved to another room, a home theater can be easily established. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a system diagram showing one embodiment of a multichannel acoustic signal reproducing apparatus according to the present invention; 
         FIG. 1B  is a schematic perspective view showing the arrangement of an acoustic signal reproducing apparatus main body in the multichannel acoustic signal reproducing apparatus shown in  FIG. 1A ; 
         FIG. 2A  is a system diagram showing another embodiment of a multichannel acoustic signal reproducing apparatus according to the present invention; 
         FIG. 2B  is a schematic perspective view showing the arrangement of an acoustic signal reproducing apparatus main body in the multichannel acoustic signal reproducing apparatus shown in  FIG. 1B ; 
         FIGS. 3A to 3D  are schematic views showing various examples of the arrangement of the multichannel acoustic signal reproducing apparatus according to the present invention; 
         FIGS. 4A and 4B  are system diagrams showing yet other embodiments of a multichannel acoustic signal reproducing apparatus according to the present invention; 
         FIGS. 5A to 5C  are schematic view showing other examples of the arrangement of the multichannel acoustic signal reproducing apparatus according to the present invention; 
         FIG. 6A  is an arrangement view showing a conventional multichannel acoustic signal reproducing apparatus; and 
         FIG. 6B  is a system diagram of the conventional multichannel acoustic signal reproducing apparatus shown in  FIG. 6A . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The embodiments of a multichannel acoustic signal reproducing apparatus according to the present invention will be described hereinafter with reference to the drawings. 
       FIGS. 1A and 1B  are a system diagram of a multichannel acoustic signal reproducing apparatus in one embodiment and a perspective view showing the overall constitution of the apparatus. 
     In  FIGS. 1A and 1B , reference symbol  20  denotes a multichannel acoustic signal reproducing apparatus main body (to be referred to as “main body” hereinafter) showing one embodiment of the present invention. This main body  20  includes at least IC&#39;s, i.e., a DVD recording and reproducing section  10  recording and reproducing a DVD, a power amplifier  16 , a digital surround decoder  14 , a controller  13 , an MPEG decoder  11  and the like. If necessary, this main body  20  also includes a CD (compact disk), a CD-ROM (compact disk read-only memory), an MD (mini-disk), a recording and reproducing apparatus capable of recording and reproducing a tape cassette or the like, an AM/FM radio, a tuner and/or the like. 
     Further, the main body  20  includes the first switching means  21 , such as switches, switching and outputting digital data before being amplified from the digital surround decoder  14  inside and outside of the main body  20  and driving various types of surround system speakers, and the second switching means  22 , such as switches, switching and outputting analog signals amplified by the power amplifier  15  or the like and driving various types of surround system speakers. 
     The housing  24  of the main body  20  is constituted to be thin in a depth direction as in the case of a wall TV  17  or the like. Speaker boxes  4  and  5  containing an FLS and an FRS which are left and right speakers, respectively and a speaker box  6  containing a CS consisting of a woofer speaker for ultra bass sound are also constituted to be thin. A grip  25  is provided on the top plate of the housing  24  for portable purposes. 
     A lid which is freely opened and closed is provided on the front surface of the housing  24  so that the DVD can be inserted from the lid. In  FIG. 1B , an insertion port  26  for a recording medium such as an MD or a cassette is provided and the speaker boxes  4  and  5  respectively containing the left and right speakers are detachable from the housing  24 . 
     Digital data terminals  27  and  28  for interfaces such as an IEEE (Institute of Electrical and Electronic Engineers 1394–1995 (to be referred to as “ITE” hereinafter)) interface and USB (Universal Serial Bus) 1.0, 2.0 or the like, and an analog input/output terminal  29  such as an S terminal are provided on the lower portion of the speaker box  6  containing the CS. 
       FIGS. 1A and 1B  show a system in which the main body  20  is provided below the wall TV  17  in front of an audience  2 , and in which the digital data terminal  27  of the main body  20  is connected to the TV  17  by one cable through the ITE interface. In this case, the audience  2  appreciates music with a system as a three-dimensional system. 
       FIGS. 2A and 2B  show another embodiment of the present invention. In this embodiment, a main body  20  is provided at the back of an audience  2  watching TV  17  so that the audience can appreciate surround phonic sound. In this case, similarly to the preceding case, it suffices to digitally supply video outputs and voice outputs from a digital data terminal  27  (or  28 ) for an interface such as ITE or USB to a TV  17 -side target through one cable  16 , thus quite facilitating handling. Left and right speakers FRS and FLS provided on the front portion of the TV  17  are used as main speakers, and left and right speakers FRS and FLS in the main body  20  are used as rear speakers RRS and RLS, respectively, and a CS is used as a RCS which emits sound right behind the audience  2 . 
     In this case, after a power amplifier  15  amplifies signals, the second switching means  22  is switched as shown in  FIG. 2A  to thereby drive the RLS, RRS and RCS in the main body  20 , and the first switching means  21  is switched as shown in  FIG. 2A  to thereby supply digital output which is not amplified yet from a digital surround decoder  14  to the TV  17 -side FRS and FLS. In this case, a D/A converter and a power amplifier are provided on the TV  17 -side. 
       FIGS. 3A to 3D  show conceptual views showing examples of the arrangement of speakers if transmitting digital outputs with the main body  20  put at the back of or side of the audience  2  as in the case of  FIGS. 2A and 2B . In  FIG. 3A , the main body  20  is provided at the back of the audience  2 , the ITE terminal  27  of the main body  20  is connected to the TV  17  by one cable  16 , the TV  17  side is controlled by the main body  20  side and reproduction is performed while the RLS and RRS are attached to the housing  24 . 
       FIG. 3B  shows a case where the USB terminal  28  of the main body  20  is connected to the TV  17  by one cable  16 , the TV  17  side is controlled by the main body  20  side, and the RLS and RRS are provided on the left and right sides of and separated from the housing  24  so as to enhance rear surround effect. 
       FIG. 3C  shows a case where the main body  20  is provided at the back of the audience, the ITE terminal  27  of the main body  20  is connected to the TV  17  by one cable  16  and the audience watches the screen of the TV  17  while using headphones  30 . 
       FIG. 3D  shows a case where the sound field space  1  in the room is narrow, the main body  20  is moved to the right side of the audience  2  and the TV  17  is connected to the USB terminal  28  of the main body  20  by one cable  16 . Even in such an arrangement as shown in  FIG. 3D , the audience  2  can sufficiently enjoy surround phonic sound. 
     In the arrangement examples of  FIGS. 2A ,  2 B and  FIGS. 3A to 3D  stated above, a commander  36  is operated toward the main body  20  side at the back of the audience  2 . In this case, since the main body  20  is located near a sofa, manual operation can be performed relatively easily. 
     While the ITE, USB 1.0 and USB 2.0 wires are used to obtain surround phonic sound according to the systems shown in  FIGS. 3A to 3D , the systems shown in  FIGS. 3A to 3D  can be replaced by a system for transmitting signals wirelessly, i.e., by an IEEE1394 wireless interface, a Blue Tooth interface or the like as shown in  FIG. 4A . 
     Namely, as shown in  FIG. 4A , if a transmitter transmission section  32  and a transmission antenna  33  each having a Bluetooth interface, for example, are provided on a main body  20  side and a transmitter reception section  35  and a reception antenna  34  are provided on a TV  17  side, thereby realizing wireless transmission. In this case, the transmitter transmission section  32  is included in a housing  24 . 
       FIG. 4B  shows yet another embodiment of the present invention. In  FIG. 4B , a main body  20  is arranged at the back of an audience  2  and connected to a TV  17 , and voice signals are supplied to an acoustic equipment  31  such as a minicomponent provided in front of the audience  2  without using TV speakers. 
       FIGS. 5A to 5C  show examples of the arrangement of speakers for obtaining surround phonic sound if an acoustic space  1  is small by using a combination of the speakers of the acoustic equipment  31  such as a minicomponent and the speakers of the main body  20  of the present invention. 
     In case of  FIG. 5A , the speakers of the TV  17  are provided in the corner of the room, the FLS and FRS of the acoustic equipment  31  provided on the right side of the audience  2  are used as main channel speakers, the speakers of the main body  20  are used as rear speakers RLS, RRS and RCS, the analog input/output terminal  29  of the main body  20 , for example, is connected to the acoustic equipment  31  by a cable  16   a  and the TV  17  is connected to the ITE terminal  27  of the main body  20  by a cable  16 . 
     In case of  FIG. 5B , the main body  20  is moved to the front of the audience  2  as in the case of  FIG. 1B , the main body  20  is connected to the TV  17  by a digital cable  16 , the FLS, CS and FRS of the main body  20  are used as main channel speakers and the speakers of the acoustic equipment  31  are used as rear speakers RLS and RRS. 
     In case of  FIG. 5C , opposite to  FIG. 5A , the speakers of the main body  20  are used as main channel speakers FLS, CS and FRS, the speakers of the acoustic equipment  31  are used as rear speakers RLS and RRS and the main body  20  is provided on the right side of the audience  2 . 
     The connections and combinations of the main body, the target and the electronic equipment of various types according to the present invention other than those described in the above embodiments can be realized and various changes and modifications can be made within the scope of the present invention. 
     Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments and that various changes and modifications could be effected therein by one skilled in the art without departing from the spirit or scope of the invention as defined in the appended claims.