JPH07162999A - Surround conversion circuit - Google Patents

Abstract

PURPOSE:To provide the surround conversion circuit capable of automatically outputting a music signal suitable for the surround system to be realized. CONSTITUTION:When a cord is connected to an output terminal T42 for C channel, a switch S42 is opened and the music signal of the C channel is outputted only from the output terminal T42. When no cord is connected, the switch S42 is closed and the music signal of the C-channel outputted to an output signal line L42 for C channel is added to the output channel signal of the L and R channels through an auxiliary line H42 and adders A1 and A4. Thus, even when the reproduction is made by the surround system without the C speaker, the music signal of the C channel is outputted through the output terminal T41 for L channel and the output terminal T43 for R channel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surround conversion circuit, and more particularly to a surround conversion circuit capable of automatically outputting an appropriate musical tone signal conforming to the surround system to be implemented.

[0002]

2. Description of the Related Art Conventionally, various surround systems are known as systems for reproducing recorded music and the like. In general, when recording music, etc., the surround system is arranged such that a plurality of microphones are arranged so as to surround the listener, and a plurality of musical sound signals recorded by this are arranged in the same arrangement as assumed at the time of recording. Say the method of playing from the speaker. According to this method, the listener can feel the presence as if he or she were at the recording site by the reproduced sound emitted from the speakers arranged around.

FIG. 7 shows an example of a speaker arrangement according to the surround system. In this example, there are six speakers: left front (L) speaker 22, center front (C) speaker 24, right front (R) speaker 26, left side (S-L) speaker 28, right side (S-R). ) Speaker 30, and subwoofer (SW) speaker 3
2 are arranged so as to surround the listener 20. Here, the SW speaker 32 is a speaker for reproducing only the low-pitched sound component extracted from one or more musical sound signals, and in principle, may be placed anywhere.

Generally, as a recording medium for musical tone signals,
CDs (compact discs), LDs (laser discs) and the like are used, but it is usually two channels that are prepared for tone signals. Therefore, a plurality of musical sound signals recorded on site are first combined into a two-channel signal by an encoder and recorded on a CD or the like. Therefore, in order for the listener to play this CD or the like and enjoy the music or the like by the surround method, after reading the two-channel musical sound signal synthesized and recorded on the CD or the like with the CD deck or the like, It is necessary to decompose into the musical tone signals of the number of channels. This signal decomposition circuit is called a surround decoder, and the surround conversion circuit is a tone signal conversion circuit equipped with such a surround decoder.

In some cases, the recorded musical tone signal is directly recorded on the recording medium without being combined into a signal of two channels. The data recorded in this way is called a multi-channel source. In addition to the input terminals for the two-channel signals, the surround conversion circuit has a multi-channel input terminal for inputting an output from such a multi-channel source and a multi-channel output from another surround decoder. There is also a configuration in which the two-channel input and the multi-channel input can be switched.

FIG. 6 shows an example of a conventional surround conversion circuit. The surround conversion circuit is roughly composed of an input terminal unit 2, an input signal line unit 4, a surround processing circuit unit 6, an output signal line unit 8 and an output terminal unit 10.

The input terminal section 2 is composed of a pair of left and right two-channel input terminals TL and TR and six multi-channel input terminals T11 to T16. The T
L is an input terminal for the left channel, TR is an input terminal for the right channel, T11 is an input terminal for the left front (L) channel,
T12 is an input terminal for the central front (C) channel, T13
Is the input terminal for the right front (R) channel, T14 is the input terminal for the left side (SL) channel, and T15 is the right side (S).
-R) channel input terminal, and T16 is a subwoofer (SW) channel input terminal.

The input signal line section 4 comprises two channel input signal lines LL and LR and six multi-channel input signal lines L11 to L16.

The surround processing circuit section 6 includes a surround decoder 12 and a surround decoder output signal line L.
21 to L26, 6 switch elements S31 to S
An input changeover switch S3 having 36 and configured so that each switch element is interlocked, six independent level controls VR11 to VR16, and six variable resistors VR.
It is composed of a volume control VR2 having 21 to VR26 and configured to be interlocked with each other, and six buffers B1 to B6.

The output signal line section 8 is composed of six output signal lines L41 to L46. The output terminal section 10 is composed of six output terminals T41 to T46.

The multi-channel input signal lines L11 to L16, the surround decoder output signal lines L21 to L26, the switch elements S31 to S36, the level controls VR11 to VR16,
Variable resistors VR21 to VR26, buffers B1 to B6, output signal lines L41 to L46, output terminal T
41 to T46 are the multi-channel input terminals T
Corresponding to 11 to T16. That is, it is an element related to the processing of the tone signals of the L, C, R, S-L, S-R, and S-W channels, respectively.

Next, the operation of this conventional surround conversion circuit will be described. A 2-channel tone signal supplied from an external source device such as a CD deck is input from 2-channel input terminals TL and TR. The musical tone signals input to TL and TR are sent to the surround decoder 12 via the 2-channel input signal lines LL and LR, respectively, and decomposed into 6-channel musical tone signals. These decomposed musical tone signals are transmitted to the one contact "2" side of the six switch elements S31 to S36 of the input changeover switch S3 via the surround decoder output signal lines L21 to L26, respectively.

On the other hand, a 6-channel multi-channel signal supplied from another external source device is input from six multi-channel input terminals T11 to T16. The inputted musical tone signals are respectively sent through six multi-channel input signal lines L11 to L16,
Six switch elements S3 of the input changeover switch S3
It is transmitted to the other contact "1" side of 1 to S36.

The input changeover switch S3 is used as a means for selecting any one of the two sets of 6-channel tone signals transmitted to the contact 1 side and the contact 2 side.

The output level of one set of 6-channel musical tone signals selected by the input changeover switch S3 is individually adjusted by six independent level controls VR11 to VR16. Further, the volume control VR2 adjusts the volume of these tone signals as a whole. The volume control VR2 has six variable resistors VR21 to VR26, which are configured to interlock with each other.

These 6 have been adjusted in volume.
Each channel tone signal has six buffers B1
Through B6 through six output signal lines L41 through L46, and six output terminals T41 through T46.
It is output from and drives external devices such as speakers.

[0017]

However, there are various surround types, and the number, type, and arrangement of speakers are different between the types. For this reason, when a general user enjoys music etc. by the surround sound system, the number and kind of output sound signals of the surround sound conversion circuit which he / she owns may not match the number, kind, etc. of the surround sound system speaker to be implemented. It was happening. Especially when the number of speakers is less than the number of output musical sound signals of the surround conversion circuit,
At the time of reproduction, the output musical sound signal corresponding to the shortage is lost, which is inconvenient. Further, if the number of output channels of the source device that supplies the tone signal to the surround conversion circuit is smaller than the number of input channels of the surround conversion circuit, the tone signal corresponding to the shortage is not input, which is inconvenient.

In order to avoid such an inconvenience, a plurality of input / output processing modes corresponding to the number, types and arrangement of speakers and the type of source equipment are provided, and the user manually selects an appropriate mode. There is a surround conversion circuit configured to do so. However, since many surround systems and source devices exist today, in such a surround conversion circuit, it is necessary to manually select a processing mode for each surround system to be implemented and for each type of source device. The operation is complicated for a general user, and therefore the operation may be mistaken.

An object of the present invention is to eliminate the inconvenience of the conventional surround conversion circuit. That is, it is an object of the present invention to provide a surround conversion circuit capable of automatically outputting an appropriate musical sound signal that matches a surround system which a user intends to implement.

[0020]

A surround conversion circuit according to claim 1 processes at least two or more input musical tone signals input from at least two or more input terminals and transmitted through an input signal line. A surround processing circuit for generating at least two or more output musical tone signals, at least two or more output terminals for supplying the output musical tone signals generated by the surround processing circuit and transmitted through the output signal lines to an external device, In the provided surround conversion circuit, the switch that makes the output signal line and the auxiliary line non-conductive when the connection cord is connected, and makes the output signal line and the auxiliary line conductive when the connection cord is not connected. Equipped with a terminal to support one or more specific tone signals among a plurality of tone signals. If the switch-equipped terminal is used as the output terminal of the channel and a connection cord is connected to the output terminal, the tone signal of the output channel is output to the output signal line of the terminal, and the connection cord is connected to the terminal. If not connected, the output tone signal of the channel is added to the tone signal of the other channel to which the connection cord is connected, among the plurality of tone signals, through the auxiliary line of the terminal, It is characterized by being configured.

A surround conversion circuit according to a second aspect of the present invention is the surround conversion circuit according to the first aspect, wherein the plurality of musical tone signals forming one group are output musical tone signals of three channels L, C and R, and a specific musical tone is generated. When the channel corresponding to the signal is the C channel and the connection cord is not connected to the output terminal of the C channel, the output musical tone signal of the channel is attenuated to a predetermined fraction through the auxiliary line of the terminal. It is characterized in that it is configured to perform addition processing on the output channel signals of the L channel and the R channel.

A surround conversion circuit according to a third aspect of the present invention is the surround conversion circuit according to the first aspect, wherein the plurality of musical tone signals forming one group are output musical tone signals of three channels L, SW and R. If the channel corresponding to the musical tone signal of is the SW channel and the connection cord is not connected to the output terminal of the SW channel, the output musical tone signal of the channel is output for a predetermined amount through the auxiliary line of the terminal. It is configured so that it is attenuated to 1 and added to the output channel signals of the L channel and the R channel.

A surround conversion circuit according to a fourth aspect of the present invention is the surround conversion circuit according to the first aspect, wherein the plurality of musical tone signals forming one group are output musical tone signals of two channels S-L and S-R. If the channel corresponding to the musical tone signal of is one of the two specified channels and the connection cord is not connected to the output terminal of the one of the specified channels, the output musical tone signal of the channel is It is characterized in that addition processing is performed on the output channel signal of the other channel than the specific one through the auxiliary line of the terminal.

A surround conversion circuit according to a fifth aspect of the present invention is the surround conversion circuit according to the first aspect, wherein a plurality of musical tone signals forming one group are output musical tone signals of four channels of L, R, SL and SR. In the case where the channels corresponding to the specific tone signal are the two channels S-L and S-R, and the connection cord is not connected to the output terminal of one of the two specific channels, If the output tone signal of the channel is added to the output channel signal of the other channel other than the specific one through the auxiliary line of the terminal, and the connection cord is not connected to the output terminal of the other channel, The output tone signal of the channel is attenuated by a predetermined amount through the auxiliary line of the terminal to output the L channel and the R channel. Each such that addition processing in phase opposition in JP, characterized in that the arrangement.

A surround conversion circuit according to a sixth aspect of the present invention processes at least two or more input tone signals input from at least two or more input terminals and input terminals and transmitted through an input signal line, and outputs at least two or more output signals. A surround conversion circuit having a surround processing circuit for generating a musical tone signal, and at least two or more output terminals for supplying an output musical tone signal generated by the surround processing circuit and transmitted through an output signal line to an external device. , When the connection cord is connected, the input signal line and the auxiliary line are made non-conductive, and when the connection cord is not connected, prepare a terminal with a switch that conducts the input signal line and the auxiliary line, An input terminal of a channel corresponding to one or more specific tone signals among a plurality of tone signals forming one group , The use of the switchable terminals,
When the connection cord is connected to the terminal, the tone signal of the input channel is used as the input of the input signal line of the terminal, and when the connection cord is not connected to the terminal, the auxiliary line of the terminal is used. Of the plurality of musical tone signals, the musical tone signal of the other specific channel to which the connection cord is connected is input to the input signal line of the terminal, and the musical tone signal of the other specific channel is input. It is characterized in that it is configured to be input to the input signal line of the terminal of the other specific channel.

According to a seventh aspect of the present invention, there is provided the surround conversion circuit according to the sixth aspect, wherein the plurality of musical tone signals forming one group are input musical tone signals of two channels of SL and SR. The channel corresponding to the musical tone signal of No. 2 is configured so that it is one specific channel of the two channels.

[0027]

In the surround conversion circuit according to claim 1, the switch-equipped terminal makes the output signal line and the auxiliary line non-conductive when the connection cord is connected, and outputs the output signal line when the connection cord is not connected. It is configured to electrically connect the signal line and the auxiliary line. Then, when the switch-equipped terminal is used as an output terminal of a channel corresponding to one or more specific tone signals among a plurality of tone signals forming one group, and a connection cord is connected to the terminal, , Output the tone signal of the output channel to the output signal line of the terminal, and if the connection cord is not connected to the terminal, output the tone signal of the channel through the auxiliary line of the terminal The tone signal is configured to be added to the tone signals of other channels to which the connection cord is connected.

Therefore, if the connection cord is not connected to the output terminal of the channel corresponding to one or more specific tone signals of the plurality of tone signals forming one group, the tone of the channel is automatically The signal can be distributed to the other channels.

In the surround conversion circuit according to the present invention, a plurality of musical tone signals forming one group are output musical tone signals of three channels L, C and R, and a channel corresponding to a specific musical tone signal is a C channel. If the connection cord is not connected to the output terminal of the C channel, the output tone signal of the channel is attenuated by a predetermined amount through the auxiliary line of the terminal and the output channel signal of the L channel and the R channel. Is configured to perform addition processing on.

Therefore, when the connection cord is not connected to the C channel, the tone signal of the channel can be automatically attenuated to a predetermined fraction and then distributed to the L and R channels.

In the surround conversion circuit according to a third aspect of the present invention, a plurality of tone signals forming one group are L, SW and R.
The output tone signal of the channel, and the channel corresponding to the specific tone signal is the SW channel, and the SW channel
When the connection cord is not connected to the output terminal of the channel, the output tone signal of the channel is attenuated by a predetermined amount through the auxiliary line of the terminal and added to the output channel signals of the L channel and the R channel. As configured.

Therefore, when the connection cord is not connected to the SW channel, the tone signal of the channel can be automatically attenuated to a predetermined fraction and then distributed to the two channels L and R. .

In the surround conversion circuit according to a fourth aspect of the present invention, a plurality of musical tone signals forming one group are S-L and S-R.
In the case where the output tone signal of a channel and the channel corresponding to the particular tone signal are one of the two specific channels and the connection cord is not connected to the output terminal of the one specific channel. The output tone signal of the channel is added to the output channel signal of the other channel other than the specific one through the auxiliary line of the terminal.

Therefore, when the connection cord is not connected to the specific one channel, the tone signal of the channel can be automatically added to the other channel.

In the surround conversion circuit according to a fifth aspect of the present invention, a plurality of musical tone signals forming one group are L, R, S-L and S.
-R four-channel output tone signal, channels corresponding to a particular tone signal are two channels SL and SR, and connected to the output terminal of one of the two channels. If the cord is not connected, the output musical tone signal of the channel is added to the output channel signal of the other channel other than the specified one through the auxiliary line of the terminal, and connected to the output terminal of the other channel. When the cord is not connected, the output tone signal of the channel is attenuated by a predetermined amount through the auxiliary line of the terminal and added to the output channel signals of the L channel and the R channel in opposite phases. ,It is configured.

Therefore, when the connection cord is not connected to one specific channel of the two channels, the tone signal of the channel can be automatically added to the other channel, and at the same time, the two channels can be added. If the connection cord is not connected to any of the channels, the tone signals of the two channels are automatically added, and then divided into two signals of opposite phase to eliminate the localization, and each is divided by a predetermined fraction. After being attenuated, it can be distributed to two channels, L and R.

According to a sixth aspect of the present invention, in the surround conversion circuit, the switch-equipped terminal is used as an input terminal of a channel corresponding to one or more specific tone signals among a plurality of tone signals forming one group, and the terminal is provided. If the connection cord is connected to, the tone signal of the input channel as the input of the input signal line of the terminal, if the connection cord is not connected to the terminal, through the auxiliary line of the terminal, Among the plurality of tone signals, the tone signal of the other specific channel to which the connection cord is connected is used as the input of the input signal line of the terminal, and the tone signal of the other specific channel is input to the other tone signal. Is configured to be the input of the input signal line of the terminal of the particular channel.

Therefore, if the connection cord is not connected to the input terminal of the channel corresponding to one or more specific tone signals among the plurality of tone signals forming one group, it is automatically connected to the other channels. The tone signal can also be used as the tone signal of the channel.

In the surround conversion circuit according to the seventh aspect, a plurality of tone signals which form one unit are S-L and S-R.
It is characterized in that the channel is an input tone signal of a channel and the channel corresponding to a particular tone signal is one of the two specified channels.

Therefore, when the connection cord is not connected to the one specific channel, the tone signal of the other channel can be automatically used as the tone signal of the specific one channel. .

[0041]

1 and 2 are block diagrams of a surround conversion circuit according to an embodiment of the present invention.

This surround conversion circuit has an input terminal section 2,
An input signal line section 4, a surround processing circuit section 6 (consisting of 6a and 6b), an output signal line section 8,
The output terminal section 10 is generally configured, and its basic configuration is the same as that of the conventional surround conversion circuit shown in FIG.

The structure of the input terminal portion 2 will be described with reference to FIG. The input terminal section 2 includes a 2-channel input terminal and a 6-channel input terminal.
The multi-channel input terminals T11 to T16 are provided. The 2-channel input terminals are n pairs of input terminals T
It is composed of L1 and TR1 or TLn and TRn. TL1 to TLn are left channel input terminals, and TR1 to TRn are right channel input terminals. The above-mentioned multi-channel input terminals T11 to T1
6 is L, C, R, respectively, as in the conventional example described above.
Input terminals for S-L, S-R, and SW channels.

In this embodiment, all the input terminals are terminals with switches. Switch terminal configuration,
The S-R channel input terminal T15 will be described as an example.

The input terminal T15 for the SR channel is a movable piece T1 as shown in FIG. 2, more specifically, FIGS.
5c, a fixed piece T15d, and a ground contact T15b.

The movable piece T15c is made of a metal having elasticity and is formed in a substantially U shape. This movable piece T1
A signal contact T15a is formed by bulging the vicinity of the center of one side of 5c, which is formed in a substantially U-shape, and a movable switch contact S15b is provided at the end of the one side following the signal contact T15a. The other substantially U-shaped side of the movable piece T15c is fixed to the main body of the terminal T15, and its end is connected to an input signal line L15 described later.

The fixing piece T15d is made of metal and is fixed to the main body of the terminal 15. One end of the fixed piece T15d is connected to the auxiliary line H15. Fixed piece T15
A fixed switch contact S15a is provided at a position of d facing the movable switch contact S15b. The fixed switch contact S15a is elastically brought into contact with the movable switch contact S15b by the elastic force of the movable piece T15c, and the switch section S15 is formed by S15a and S15b.
15 is formed.

Therefore, as will be described later, the switch section S15 makes the input signal line L15 and the auxiliary line H15 non-conductive when the connection cord is connected, and makes the input when the connection cord is not connected. Signal line 1
5 and the auxiliary line H15 are electrically connected.

Next, the connection state of the above-mentioned auxiliary line will be described. As shown in FIG. 2, the auxiliary line H15 of the S-R channel input terminal T15 is connected to the S-L channel input signal line L14 described later. Similarly, the auxiliary lines HR1 to HRn of the right channel input terminals TR1 to TRn of the two channel input terminals are respectively connected to the left channel input signal line L.
It is connected to L1 to LLn.

On the other hand, input terminals other than these, that is,
Multi-channel input terminals T11 to T14 and T1
6, and input terminals TL1 to TLn for the left channel
The auxiliary line of is grounded.

The input terminals T11 to T16 and TL1 or TR1, TLn or T1.
The ground contacts of Rn are all grounded, as shown in FIG.

Next, the configurations of the input signal line section 4, the surround processing circuit section 6, the output signal line section 8 and the output terminal section 10 will be described with reference to FIGS. 2 and 1.

As shown in FIG. 2, the input signal line section 4
Has a two-channel input signal line and six multi-channel input signal lines L11 to L16. The 2-channel input signal line is composed of n pairs of input signal lines LL1 and LR1 or LLn and LRn.

As shown in FIGS. 1 and 2, the surround processing circuit section 6 has two switch elements S2L and S2R each having n contacts, and both switch elements are configured to interlock with each other. Channel input selector switch S2, surround decoder 12, surround decoder output signal lines L21 to L26, six switch elements S31 to S36, and input selector switches S3, 6 independent, each switch element being configured to work together. Level control VR11 to VR16,
A volume control VR2 having six variable resistors VR21 to VR26, which are configured to interlock with each other, six buffers B1 to B6, a buffer B1 and an output signal line L41 which will be described later are provided. It includes an adder circuit A1, an adder circuit A3 provided between the buffer B3 and the output signal line L43, and an adder circuit A4 provided between the buffer B4 and the output signal line L44. The output signal line section 8 includes six output signal lines L4.
1 to L46. The output terminal unit 10 includes six output terminals T41 to T46.

Next, the connection relation of each of the above-mentioned elements will be described. As shown in FIG. 2, the signal contacts of the left channel input terminals TL1 to TLn are provided on the switch element S2L of the 2-channel input changeover switch S2 via the input signal lines LL1 to LLn.
Each of the contacts "1" to "n" is connected. Similarly, the signal contacts of the right channel input terminals TR1 to TRn are respectively connected to the n contacts "1" to "n" provided in the switch element S2R via the input signal lines LR1 to LRn. ,It is connected.

The output terminals of the switch elements S2L and S2R are the input terminals L1 and R of the surround decoder 12.
1 are respectively connected. Further, the output terminals T21 to T26 of the surround decoder 12 are connected to the surround decoder output signal lines L21 to L26.
To the contact "2" provided on the six switch elements S31 to S36 of the input changeover switch S3,
Each is connected.

On the other hand, the multi-channel input terminal T1
The signal contacts 1 to T16 are connected to the contacts "1" provided on the switch elements S31 to S36 of the input changeover switch S3 via the multi-channel input signal lines L11 to L16, respectively.

The output terminals provided to the six switch elements S31 to S36 of the input changeover switch S3 are connection lines L31 to L36, and as shown in FIG. 1, the six independent level controls VR11 to VR1.
6. Six variable resistors VR21 to VR26 of the volume control VR2 and six buffers B1 to B6 are connected in series in this order.

The output terminals of the buffers B1, B3 and B4 are the first input terminals A of the adders A1, A3 and A4.
11, A31 and A41, respectively.
The outputs A19, A39 and A49 of these adders are
The output signal lines L41, L43 and L44 are connected to the signal contacts of the output terminals T41, T43 and T44, respectively.

On the other hand, the output ends of the buffers B2, B5 and B6 are directly connected to the signal contacts of the output terminals T42, T45 and T46 via the output signal lines L42, L45 and L46, respectively. .

Further, the output terminals T42, T44, T
45 and T46 are terminals with a switch having the same structure as that used for the input terminal 11 and the like.

The auxiliary line H42 of the output terminal T42 is connected to the second input terminals A12 and A32 of the adders A1 and A3.
It is connected to the. Similarly, the auxiliary line H46 of the output terminal T46 is connected to the third input terminals A13 and A33 of the adders A1 and A3. On the other hand, the auxiliary line H45 of the output terminal T45 is connected to the second input terminal A of the adder A4.
It is connected to 42. The auxiliary line H44 of the output terminal T44 is connected to the fourth input terminal A14 of the adder A1 and is also connected to the fourth input terminal A34 of the adder A3 via the phase inverter Y. .

The output terminals T41 and T43 are normal terminals having no switch. Also, the output terminal T4
The ground contacts 1 to T46 are all grounded.

Next, the operation of the surround conversion circuit having the above configuration will be described with reference to FIGS.

As shown in FIG. 2, the surround conversion circuit according to the above-mentioned embodiment has 6-channel multi-channel input terminals T11 to T16, and also has n pairs of input terminals TL1 and T1 as 2-channel input terminals.
It has R1 or TLn and TRn. This is because when there are a plurality of external source devices, all the external devices are connected to the input terminals of the surround conversion circuit.

With such a connection, when changing the external device on the input side, it is only necessary to change the changeover switch of the surround conversion circuit without replacing the connection cord. That is, in this embodiment, a maximum of n 2-channel source devices and one 6-channel source device are used.
Multi-channel source devices for channels can be connected at the same time.

In this case, for example, when the tone signal of the 2-channel source device connected to the 2-channel input terminals TL1 and TR1 is processed and is to be output,
Set the switching position of the 2-channel input selector switch S2 to "
It should be set to "1" and the switching position of the input selector switch S3 should be set to "2". Further, the musical tone signals of the multi-channel source devices connected to the six-channel multi-channel input terminals T11 to T16 are unchanged. When the output is desired, the input selector switch S3 may be switched to the "1" position.

Next, the operation of the switch-equipped terminal used in this embodiment will be described with reference to the SR channel input terminal T.
15 will be described as an example.

As shown in FIG. 4, the connecting cord is the terminal T1.
When not connected to 5, the input signal line L15 and the auxiliary line H15 are in a conductive state.

When the connecting cord is connected to the terminal T15,
As shown in FIG. 5, the side surface portion near the tip of the signal pin P of the connection cord comes into contact with the signal contact T15a of the terminal T15, resisting the elastic force of the movable piece T15c, and acting as the signal contact T15.
Push down a. By pushing down the signal contact T15a, the fixed contact S15a and the movable contact S15b of the switch S15 are separated from each other.

Therefore, by connecting the connection cord, the signal pin P of the connection cord becomes conductive with the input signal line L15 via the signal contact T15a of the terminal T15, and the input signal line L15 is connected to the auxiliary line H1.
It becomes non-conductive with 5. That is, the switch-equipped terminal in this embodiment makes the input signal line L15 and the auxiliary line H15 non-conductive when the connection cord is connected, and the input signal line 15 and the auxiliary line H15 when the connection cord is not connected. It is configured to conduct the line H15.

Next, the connection state of the input / output terminals will be divided into cases, and the operation of the surround conversion circuit according to this embodiment in each connection state will be described.

When the number of channels of the external device connected is equal to the number of input / output channels of the surround conversion circuit, that is, the output of the source device on the input side is encoded 2-channel output or 6-channel multi-channel output. And L as an external device on the output side,
When six speakers of C, R, S-L, S-R, and S-W are prepared, and these external devices are connected to the input / output terminals of the surround conversion circuit without excess or deficiency. The operation of the surround conversion circuit according to this embodiment is
This is similar to the case of the conventional surround conversion circuit described above.

In this case, the output voltages EL, EC, ER, ESL, ESR and ESW of the output terminals T41 to T46.
Is expressed by the following equation.

EL = eL EC = eC ER = eR ESL = eSL ESR = eSR ESW = eSW where eL, eC, eR, eSL, eSR and eSW
Are output voltages of the buffers B1 to B6, respectively.

Next, the operation when a specific output terminal is not connected will be described. As shown in FIG. 7, the tone signals of the L, C, and R channels are common in that they are signals to be played in front of the listener, and these three signals form one unit. .

First, the case where the connection cord is not connected only to the C-channel output terminal T42 will be described. In this case, the terminal T42 has a switch, and
The switch S42 is closed, as in the case of the input terminal shown in FIG. Therefore, the C-channel output signal line L42 is in conduction with the auxiliary line H42. Therefore, FIG.
As shown in, C output from the buffer B2
The channel tone signal is distributed and transmitted to the second input terminals A12 and A32 of the adders A1 and A3 through the C channel output signal line L42 and the auxiliary line H42.

As will be described in detail later, the adder A1 attenuates the transmitted C channel musical tone signal to 1 / SQRT (2), and the attenuated signal and the first input via the buffer B1. The L channel musical tone signal input from the terminal A11 is added, and the summed musical tone signal is output from the output terminal A19. This added output signal is L
It is output from the L channel output terminal T41 via the channel output signal line L41, and is reproduced by the L speaker connected thereto. In addition, here SQRT
(A) represents the square root of a.

Similarly, the adder A3 attenuates the tone signal of the C channel to 1 / SQRT (2), adds this to the tone signal of the R channel, and outputs the sum from the output end A39. Similarly, the added output signal is output from the R channel output terminal T43 via the R channel output signal line L43 and reproduced by the R speaker connected thereto.

Therefore, even if the reproduction is performed by the surround system having no C speaker, the tone signal of the C channel is not lost. That is, when the connection cord is not connected to the output terminal T42 for C channel, the tone signal of the C channel is automatically attenuated to 1 / SQRT (2) and added to the tone signals of the L and R channels, And through the R speaker.

In this embodiment, the tone signal of the C channel is attenuated to 1 / SQRT (2). However, this is in consideration of the pitch of the listener, and unless the pitch is remarkably impaired. The degree of attenuation can be set arbitrarily.

The output voltage of the output terminal in this case is expressed by the following equation.

EL = eL + eC / SQRT (2) ER = eR + eC / SQRT (2) ESL = eSL ESR = eSR ESW = eSW S-W channel tone signals are bass components extracted from L and R channel tone signals. It is often a thing. That is, the tone signals of the L, R and SW channels are considered to be one unit with these three signals.

Next, the output terminal T46 for the SW channel
Only when the connection cord is not connected will be described. Also in this case, the switch S46 of the terminal T46 is closed. Therefore, the SW signal output signal line L46 is in conduction with the auxiliary line H46. Therefore, the tone signal of the SW channel output through the buffer B6 is output to the third input ends A13 and A33 of the adders A1 and A3 through the SW channel output signal line L46 and the auxiliary line H46. Distributed and transmitted.

The transmitted sound signal of the SW channel is attenuated as in the case of the C channel and then added to the sound signals of the L and R channels, and finally, the L and R channel output terminals T41 and T43. Is output from and is reproduced by the L and R speakers connected thereto.

Therefore, even if the reproduction is performed by the surround system having no SW speaker, the music signal of the SW channel is not lost. That is, when the connection cord is not connected to the SW terminal for the SW channel, the tone signal of the SW channel is automatically converted to 1 / S.
It is attenuated by QRT (2), added to the tone signals of the L and R channels, and reproduced through the L and R speakers.

The output voltage of the output terminal in this case is expressed by the following equation.

EL = eL + eSW / SQRT (2) EC = eC ER = eR + eSW / SQRT (2) ESL = eSL ESR = eSR In addition, the output terminal T for the C channel and the SW channel is used.
The output voltage of the output terminal when the connecting cord is not connected to both 42 and T46 is expressed by the following equation.

EL = eL + (eC + eSW) / SQRT (2) ER = eR + (eC + eSW) / SQRT (2) ESL = eSL ESR = eSR The tone signals of the SL and SR channels are shown in FIG. As described above, they are common in that they are signals to be reproduced on the side of the listener, and these two signals form one unit.

Next, the output terminal T45 for the SR channel
Only when the connection cord is not connected will be described. In this case, the switch S45 of the terminal T45 is closed. Therefore, the S-R channel output signal line L45 is in conduction with the auxiliary line H45. Therefore, as shown in FIG. 1, the S-R channel tone signal output through the buffer B5 is transmitted through the S-R channel output signal line L45 and the auxiliary line H45 to the second input terminal of the adder A4. It is transmitted to A42.

The adder A4 sends the transmitted tone signal of the SR channel and the first input terminal A41 via the buffer B4.
The input signal is added to the S-L channel musical tone signal, and the summed musical tone signal is output from the output terminal A49. The added output signal is output from the SL channel output terminal T44 via the SL channel output signal line L44 and reproduced by the SL speaker connected thereto.

Therefore, even if the reproduction is performed by the surround system without the S-R speaker, the tone signal of the S-R channel is not lost. That is, when the connection cord is not connected to the output terminal T45 for the S-R channel, the tone signal of the S-R channel is automatically S-L.
It is added to the tone signal of the channel and played back through the SL speaker.

The output voltage of the output terminal in this case is represented by the following equation.

EL = eLEC = eC ER = eR ESL = eSL + eSR ESW = eSW Note that only the output terminals T45 and T46 for the SR channel and the SW channel are output terminals when the connection cord is not connected. The output voltage of is expressed by the following equation.

EL = eL + eSW / SQRT (2) EC = eC ER = eR + eSW / SQRT (2) ESL = eSL + eSR The tone signals of the L, R, SL and SR channels are as shown in FIG. The two are common in that they are signals that should be reproduced approximately on the side of the listener, and these four signals form one unit.

Next, the case where the connection cords are not connected to both the output terminals T45 and T44 for the SR and SL channels will be described. In this case, the terminal T
The switch S45 of 45 is closed. Therefore, as described above, the SR output from the buffer B5 is output.
The tone signal of the channel is added to the tone signal of the SL channel output through the buffer B4 by the adder A4, and the tone signal which is the sum is output from the output terminal A49 of the adder A4.

Further, it is based on the switch S44 of the terminal T44. Therefore, the S-L channel output signal line L44 is in conduction with the auxiliary line H44. Therefore, the added tone signal is transmitted to the fourth input terminal A14 of the adder A1 through the S-L channel output signal line L44 and the auxiliary line H44, and the phase is inverted by the phase inverter Y. Then, it is transmitted to the fourth input terminal A34 of the adder A3.

As in the case of the C channel, these transmitted musical tone signals are attenuated and then added to the musical tone signals of the L and R channels, respectively, and finally, the L and R channels.
Output from the channel output terminals T41 and T43,
It is reproduced by the L and R speakers connected to this.

Therefore, even if the playback is the surround sound system without the SR and SL speakers, the SR
And, the tone signal of the S-L channel is not lost. That is, the output terminal T45 for S-R and S-L channels
If the connection cord is not connected to T44 and T44, the tone signals of these channels are automatically added, and the phases are made opposite to each other, and then 1 / SQRT (2)
Attenuated to add to the tone signal of the L and R channels,
And through the R speaker.

[0100] As described above, the opposite phases are generated when a signal obtained by adding the tone signals of the SR and SL channels is reproduced from the L and R channel speakers. This is to prevent it. By doing so, the listener can enjoy music and the like without feeling uncomfortable.

The output voltage of the output terminal in this case is expressed by the following equation.

EL = eL + (eSL + eSR) / SQRT (2) EC = eC ER = eR− (eSL + eSR) / SQRT (2) ESW = eSW Incidentally, the SL channel, the SR channel and the SW channel.
The output voltage of the output terminal when the connection cord is not connected to only the three output terminals of the channel output terminals T44, T45 and T46 is expressed by the following equation.

EL = eL + (eSL + eSR + eSW) / SQRT (2) EC = eC ER = eR- (eSL + eSR-eSW) / SQRT (2) Also, the output terminal T41 for the L channel and the R channel.
The output voltage of the output terminal when the connecting cord is connected only to both T and T42 is expressed by the following equation.

EL = eL + (eC + eSL + eSR + eSW) / SQRT (2) ER = eR + (eC-eSL-eSR + eSW) / SQRT (2) Next, in the surround conversion circuit shown in this embodiment,
Figure 2 shows the operation when a specific input terminal is not connected.
It will be described based on. As described above, the tone signals of the S-L and S-R channels form one unit with these two signals.

First, regarding the multi-channel input terminal, S- of the two input terminals corresponding to these signals is used.
A case where a connection cord is not connected to the R channel input terminal T15 will be described.

In this case, the terminal T15 has a switch, and the switch S15 is closed as shown in FIG.
That is, the S-R channel input signal line L15 is in conduction with the auxiliary line H15. Therefore, as shown in FIG. 2, the S-L channel tone signal input through the S-L channel input terminal T14 is S-L.
Channel input signal line L14, auxiliary line H15
Through the input signal line L15 for the SR channel.

At the same time, the tone signal of the S-L channel is S
It is also transmitted to the -L channel input signal line L14.

Therefore, when the multi-channel source device on the input side does not have an output terminal corresponding to the SR channel, for example, the source device is SR and SL.
Even if there is only one tone signal corresponding to the channel and this is output from one terminal as the S channel tone signal, the input tone signal of the S-R channel of the surround conversion circuit does not exist. It never enters the input state.

That is, the input terminal T for the SR channel
When the connection cord is not connected to 15, the S channel musical tone signal input to the S-L channel can be automatically distributed to the S-L and S-R channel musical tone signals. Therefore, the reproduction is S-R and S-L.
In the case of the surround system having both speakers, the S channel musical tone signal is reproduced through both the SL speakers and the SR speakers.

As described above, the musical tone signals encoded in the two channels include all the musical tone signals at the time of recording, and a pair of left and right signals form one unit.

Next, regarding the 2-channel input terminal, the case where the connection cord is not connected to the right channel input terminal TR1 of the two input terminals corresponding to these signals will be described. Also in this case, the switch SR1 of the terminal TR1 is closed. That is, the right channel input signal line LR1 is in conduction with the auxiliary line HR1.
Therefore, as shown in FIG. 2, the tone signal of the left channel input through the left channel input terminal TL1 passes through the left channel input signal line LL1 and the auxiliary line HR1 and the right channel input signal line LR1. Be transmitted to.

At the same time, the left channel tone signal is also transmitted to the left channel input signal line LL1.

Therefore, when the source device on the input side does not have an output terminal corresponding to the right channel, for example,
Even if the source device has only one channel of the tone signal and outputs it from one terminal, the input tone signal of the right channel of the surround conversion circuit is in the state of no input. Absent.

That is, the right channel input terminal TR1
If the connection cord is not connected to, the 1-channel tone signal input to the left channel can be automatically distributed to the left and right channel tone signals.
Therefore, in the case where the reproduction is the surround sound system including a large number of speakers, the 1-channel musical tone signal is reproduced through the large number of speakers.

Next, FIG. 3 shows an example of a concrete circuit of the output section 12 in the surround conversion circuit according to this embodiment. In the specific example shown in FIG. 3, the adders A1 to A4 and the phase inverter Y described above are composed of operational amplifiers and resistors.

The adder A1 is composed of A1a and A1b, and is composed of three operational amplifiers OP11 to OP13 and nine resistors R11 to R19. Here, the resistance value of the resistors R11 to R13 is "S
QRT (2) * R ″ and resistors R14 to R19
Has a resistance value of "R". By setting the resistance value of the resistors R11 to R13 to "SQRT (2) * R", the tone signal input through these resistors is reduced to 1 / SQ.
It is attenuated to RT (2).

The adder A3 has two operational amplifiers OP31.
And OP32, and seven resistors R31 to R3
It is composed of 7. Here, resistors R31 to R
The resistance value of 33 is "SQRT (2) * R", and the resistance values of the resistors R34 to R37 are "R".

The adder A4 has two operational amplifiers OP41.
And OP42 and five resistors R44 to R4
It is composed of 8. Here, resistors R44 to R
The resistance values of 48 are all "R".

The phase inverter Y is a part of the elements constituting the adder A3, that is, the operational amplifier OP32,
It is composed of resistors R33 and R37. This utilizes the phase inversion function of the operational amplifier, that is, the function that, when the positive phase input terminal 34 is grounded, the signal input from the negative phase input terminal 36 is output in the opposite phase.

[0120]

According to the surround conversion circuit of the present invention, the switch-equipped terminal is used as an output terminal of a channel corresponding to one or two or more specific musical tone signals among a plurality of musical tone signals forming one group, When the connection cord is not connected to the terminal, the output musical tone signal of the channel is converted to the musical tone signal of the other channel to which the connection cord is connected among the plurality of musical tone signals through the auxiliary line of the terminal. It is configured to perform addition processing.

That is, when the connection cord is not connected to the output terminal of the channel corresponding to one or more specific tone signals of the plurality of tone signals forming one group, the tone of the channel is automatically The signal can be distributed to the other channels.

Therefore, according to this surround conversion circuit, it is possible to automatically output an appropriate tone signal that matches each surround system.

According to the surround conversion circuit of the second aspect, when the connection cord is not connected to the output terminal of the C channel, the output tone signal of the channel is attenuated to a predetermined fraction through the auxiliary line of the terminal. It is configured to perform addition processing on the output channel signals of the L channel and the R channel.

Therefore, according to this surround conversion circuit, it is possible to automatically output an appropriate tone signal even for the surround system having no C speaker.

The surround conversion circuit according to claim 3 is SW
When the connection cord is not connected to the output terminal of the channel, the output tone signal of the channel is attenuated by a predetermined amount through the auxiliary line of the terminal and added to the output channel signals of the L channel and the R channel. As configured.

Therefore, according to this surround conversion circuit, it is possible to automatically output an appropriate tone signal even for a surround system having no SW speaker.

The surround conversion circuit according to claim 4 is S-L
If the connection cord is not connected to the output terminal of a specific one of the two channels of S and R,
The output tone signal of the channel is configured to be added to the output channel signal of the other channel other than the specific one through the auxiliary line of the terminal.

Therefore, according to this surround conversion circuit, it is possible to automatically output an appropriate musical tone signal even for the surround sound system which does not have either the SL speaker or the SR speaker. .

The surround conversion circuit according to claim 5 is S-L
If the connection cord is not connected to the output terminal of one of the two specific channels of S-R and S-R, the output musical tone signal of that channel is passed through the auxiliary line of the terminal to the other of the other specific channels. Addition processing is performed on the output channel signal of the channel, and when the connection cord is not connected to the output terminal of the other channel, the output tone signal of the channel is attenuated to a predetermined fraction through the auxiliary line of the terminal. The output channel signals of the L channel and the R channel are configured to perform addition processing in opposite phases.

Therefore, according to this surround conversion circuit, an appropriate musical tone signal is automatically output even for a surround sound system which does not have any one or both of the SL speaker and the SR speaker. be able to.

According to a sixth aspect of the present invention, there is provided a surround conversion circuit, wherein the switch-equipped terminal is used as an input terminal of a channel corresponding to one or more specific tone signals among a plurality of tone signals forming one group, If the connection cord is not connected to, through the auxiliary line of the terminal,
Of the plurality of tone signals, the tone signal of another specific channel to which the connection cord is connected is used as the input of the input signal line of the terminal.

That is, when the connection cord is not connected to the input terminal of the channel corresponding to one or more specific tone signals among the plurality of tone signals forming one group, the other channels are automatically connected to each other. The tone signal can also be used as the tone signal of the channel.

Therefore, according to this surround conversion circuit, it is possible to automatically input an appropriate tone signal that matches each input source.

In the surround conversion circuit according to the seventh aspect, a plurality of musical tone signals forming one group are S-L and S-R.
It is characterized in that the channel is an input tone signal of a channel and the channel corresponding to a particular tone signal is one of the two specified channels.

Therefore, according to this surround conversion circuit, it is possible to automatically input an appropriate musical tone signal to an input source that does not have either the SL channel or the SR channel. .

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an output side portion of a surround conversion circuit according to an embodiment of the present invention.

FIG. 2 is a drawing showing a configuration of an input side portion of a surround conversion circuit according to an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a specific circuit of an output side portion of a surround conversion circuit according to an embodiment of the present invention.

FIG. 4 is a schematic diagram when a connection cord is not connected to the switch-equipped terminal used in the surround conversion circuit according to the embodiment of the present invention.

FIG. 5 is a schematic diagram when a connection cord is connected to a terminal with a switch used in a surround conversion circuit according to an embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of an example of a conventional surround conversion circuit.

FIG. 7 is a diagram showing an example of speaker arrangement according to a surround method.

[Explanation of symbols]

 T41 ... L channel output terminal T42 ... C channel output terminal T43 ... R channel output terminal L42 ... C channel output signal line S42 ... Switch H42 ... Auxiliary line A1, A3 ... Adder

Claims (7)

[Claims] 1. Surrounding processing for processing at least two or more input musical tone signals input from at least two input terminals and transmitted through an input signal line and generating at least two or more output musical tone signals. Circuit, a surround conversion circuit equipped with at least two or more output terminals for supplying the output musical tone signal generated by the surround processing circuit and transmitted through the output signal line to the external device, and the connection cord is connected. If so, the output signal line and the auxiliary line are made non-conductive, and if the connection cord is not connected, prepare a terminal with a switch that makes the output signal line and the auxiliary line conductive, and The terminal with the switch is attached to the output terminal of the channel corresponding to one or more specific tone signals of the tone signals. If the connection cord is connected to the terminal, output the tone signal of the output channel to the output signal line of the terminal.If the connection cord is not connected to the terminal, output the channel. A surround conversion circuit configured to add a tone signal to a tone signal of another channel to which a connection cord is connected among the plurality of tone signals through the auxiliary line of the terminal. 2. The surround conversion circuit according to claim 1, wherein the plurality of musical tone signals forming one group are output musical tone signals of three channels L, C and R, and a channel corresponding to a specific musical tone signal is If it is a C channel and the connection cord is not connected to the output terminal of the C channel, the output musical tone signal of the channel is attenuated by a predetermined amount through the auxiliary line of the terminal and output of the L channel and the R channel. Characterized by being configured to perform addition processing on the channel signal. 3. The surround conversion circuit according to claim 1, wherein the plurality of musical tone signals forming one group are output musical tone signals of three channels L, SW and R, and a channel corresponding to a specific musical tone signal. Is a SW channel, and if a connection cord is not connected to the output terminal of the SW channel, the output musical tone signal of the channel is attenuated to a predetermined fraction through the auxiliary line of the terminal and L The configuration is such that addition processing is performed on the output channel signals of the channel and the R channel. 4. The surround conversion circuit according to claim 1, wherein a plurality of tone signals forming one group are S-L and S-.
R is an output musical tone signal of two channels, a channel corresponding to a specific musical tone signal is one specific channel of the two channels, and a connection cord is connected to an output terminal of the specific one channel. If not, the output musical tone signal of the channel is added to the output channel signal of the other channel other than the specific one through the auxiliary line of the terminal. 5. The surround conversion circuit according to claim 1, wherein a plurality of tone signals forming one unit are L, R, and SL.
And S-R are four channels of output musical tone signals, and channels corresponding to specific musical tone signals are S-L and S
-R is two channels, and when the connection cord is not connected to the output terminal of one of the two specific channels, the output musical tone signal of the channel is passed through the auxiliary line of the terminal,
Addition processing to the output channel signal of the other channel other than the specific one, when the connection cord is not connected to the output terminal of the other channel, the output musical tone signal of the channel through the auxiliary line of the terminal, L decays to a predetermined fraction
The output channel signals of the R channel and the R channel are configured to perform addition processing in opposite phases, respectively. 6. At least two or more input terminals, surround processing for processing at least two or more input musical tone signals input from the input terminals and transmitted through an input signal line, and generating at least two or more output musical tone signals. Circuit, a surround conversion circuit equipped with at least two or more output terminals for supplying the output musical tone signal generated by the surround processing circuit and transmitted through the output signal line to the external device, and the connection cord is connected. If so, the input signal line and the auxiliary line are made non-conductive, and if the connection cord is not connected, prepare a terminal with a switch that makes the input signal line and the auxiliary line conductive, and The terminal with the switch is attached to the input terminal of the channel corresponding to one or more specific tone signals of the tone signals. If the connection cord is connected to the terminal, the tone signal of the input channel is used as the input signal line input of the terminal, and if the connection cord is not connected to the terminal, Among the plurality of musical tone signals through the auxiliary line, the musical tone signal of the other specific channel to which the connection cord is connected is used as the input of the input signal line of the terminal, and the musical tone signal of the other specific channel is input. A surround conversion circuit, wherein a signal is configured to be input to an input signal line of a terminal of the other specific channel. 7. The surround conversion circuit according to claim 6, wherein a plurality of tone signals forming one group are S-L and S-.
It is an input musical tone signal of two channels of R, and the channel corresponding to a specific musical tone signal is configured so as to be one specific channel of the two channels.