JPS5922277A - Acoustic multiplex reproducing device - Google Patents

Abstract

PURPOSE:To reproduce signals from different sound sources simultaneously through a speaker and a headphone by providing a changeover switch to a multi-sound source type audio system to be mounted on vihicle. CONSTITUTION:Input/output terminals i1, i2, o1, o2 of an analog switch SW conduct any one of audio signals AM, FM and TAPE to an amplifier AF1 and the input/output terminals i3, i4, o3, o4 conduct any one of them to an amplifier AF2. A latch RT selects one of switches SW (on the amplifier AF side). Key codes DA-DD for the latch are entered at timing L1, L2. The table shows the relation between the key codes and functions. When the code DA-DD are switched to speaker and headphone code by the prestage controller and a signal is inputted to latches RT1, RT2 at the different timing L1, L2, different signals can be reproduced by the speaker and headphone.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an audio multiplex reproduction device that simultaneously reproduces signals from different sound sources using a speaker and a henodophone.

The sound sources of the public hearing system are AM broadcasts, FM broadcasts, tapes, and records, but a single speaker system cannot reproduce these at the same time. FIG. 1 is a block diagram showing an in-vehicle audio system, taking as an example a three-sound source system including a cassette deck, iAM tuner 2, and FM tuner 3. The cassette deck 1 is controlled by a digital controller 4 using a microcomputer, and the audio signal TAPE obtained by the playback HD is applied to one terminal of a function changeover switch SW through an equalizer BQ and an amplifier AMP. The tuner 2.3 uses a PLL tuning method, and receives the output of a phase-locked loop (PLL) 5 through a high frequency stage and a frequency mixing section to perform tuning. A microcomputer 6 called a tuner controller controls the frequency of the PLL 5. The audio signals AM and FM obtained by the tuner 2.3 are guided to the remaining two terminals of the switch SW.

Since the conventional changeover switch SW has a choice between mechanical and electronic types, only one of the audio signals TAPE, AM, and FM is supplied to the audio amplifier AF. SP
is a speaker as a reproduction source. Although headphones are also available as a reproduction source, the illustrated function switching only reproduces the same signal from both the speakers and headphones. 7 is a key matrix that indicates various things to the cassette deck or tuner, and the key operation information is stored in a microcomputer 8 called a key controller.
and relayed to controller 4.6. 9
is a remote controller having the same functions as the key matrix 7, and its key operation information is similarly encoded in the key controller 8. The passage key matrix 7 is installed near the driver's seat, and the remote controller 9 is installed in the rear seat.

The present invention enables an audio system having two or more sound sources to simultaneously reproduce all audio signals using a speaker and a henodophone.

The audio multiplex playback device of the present invention is equipped with a changeover switch that allows a signal from any sound source of a multi-sound car audio system to be played back through a speaker, and at the same time allows a signal from a different sound source to be played back through headphones. This will be described in detail below with reference to the illustrated embodiments.

Fig. 2 shows an embodiment of the present invention in which a speaker SP is used as the main acoustic transducer and a Hetbon HP is used as the sub-acoustic transducer, and shows the configuration after the switch section that receives the audio signals AM, FM, and TAPE in Fig. 1. It is something that AF+ is a speaker amplifier, and AF2 is a hesotopone amplifier, which are provided exclusively. In addition, PLL5 in Fig. 1 has two systems,
By dynamically driving these, AM and FM can be received simultaneously. sw -5w3. is an analog switch swl that selects which of audio signal 1 AM, FM, or TAPE is guided to amplifier A or F1.

~sw3. is an analog switch that similarly selects which of them is led to the amplifier AF2.

These switches are controlled by the output of a latch RT which receives a key code from the key controller 8 of FIG. 1 either directly or via another controller.

In this device, audio<N% AM, F
A designation to generate any two of M and T APR at the same time is made using the key matrix 7 and remote controller 9 in FIG. In the following, it is assumed that the remote control controller is used to select a sound source for the headphone HI), and the key matrix 7 is used to select a sound source for the speaker SP. However, it is also possible to control both the speaker SP1 and the headphones HP by instructions from the remote controller 9. If it is possible to specify such a function, for example, when an FM broadcast is being broadcast from the speaker SP into the passenger compartment, switch SW21 is turned on), and switch SW1 is turned on by operating the remote controller 9 from the rear seat.
□If you turn on s w32, you can listen to AM broadcasts or TAPE performances through the headphones HP.

Figure 3 shows a specific example of the changeover switch section, RT+.

RT2 is a launch that is obtained by dividing the latch RT shown in FIG. 2 into speaker and headbond parts. SW+ to SW3 are IC analog switches, i + "- i4 is an input terminal, stones 1 to 4 are output terminals, and C1%C4 are control switches.The analog switch SW'+ is the one shown in Fig. 2. switch S
This is for AM, which corresponds to W++, S W12. In this example, it is assumed that the playback source is for stereo, and a signal path for R is provided, with il, i2, -01, 02 connected to switch SW, , and i 3, ia, 03 ,04
Gas, isochi sw,. corresponds to analog switch S
The same applies to W2 and SW3, and the FM analog switch SW2 is the switch SW2+ in FIG.
S Equivalent to W22, analog switch S for TAPE
W3 corresponds to the switches SW3 and SW32 in the figure.

The latch RT+ is the output F1 to F3 and the switch SW I”
S W ] on the speaker side (amplifier AF+ side). Furthermore, the latch RT2 selects the henophone side (amplifier AF2 side) of the switches SW1 to SW3 using the outputs S1 to S3. The key codes for these lunches are at timing L1. It is taken in by L2. The table below shows the relationship between key codes and functions.

Table 1 As is clear from the above table, the definitions of coats DA to D are the same for both coats. The controller at the previous stage switches the code for speakers and headphones at the timing shown in Figure 4 (of course, the contents depend on the key matrix and remote controller), and then switches it to a different timing L.
l, latch RTI at L2.

By importing the signal into RT2, different signals can be reproduced between the speaker SP and the headphones HP. In the example in the same figure, the AM coat specified by key matrix 7 is launched at RT1.
The figure shows how the FM code specified by the remote 21-[1-ra 9 is fetched into the latch RT2. Note that the undefined court can be used, for example, to specify a player.

As described above, according to the present invention, the interior of a car can be acoustically multiplexed like an airplane, and it is possible to listen to music different from the music output from the speakers. becomes.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the audio system of Genji Tatsuon; Fig. 2 is a block diagram showing the main parts of an embodiment of the present invention;
FIGS. 3 and 4 are block diagrams and time charts showing specific examples thereof. In the figure, 1 to 3 are sound sources, SP is a speaker, HP is a headphone, 5WI-8W3. SWl. ~SW, 2 is a changeover switch. Applicant: Minoru Aoyagi, Patent Attorney, Fujitsu Ten Co., Ltd.

Claims (1)

[Claims] An acoustic multiplexing system that is characterized by being equipped with a changeover switch that allows a signal from an arbitrary sound source of an in-vehicle audio system to be played back by a speaker, and at the same time allows a signal from a different sound source to be played back by headphones. playback device.