KR20030083579A - Loudspeaker arrangement and switching apparatus therefor - Google Patents

Abstract

An acoustic sound reproduction apparatus for a first audio signal is provided, wherein the acoustic sound reproduction apparatus has an input terminal, a selection switch, and at least one loudspeaker for receiving a second audio signal. At least one speaker is driven by a signal output from one of the first or second audio signals via a selection switch. As a result, the acoustic sound reproducing apparatus and the apparatus for providing the second audio signal can use one speaker or speaker set in common. When an external audio signal is selected, the internal speaker (s) become part of the external speaker arrangement for the surround sound system. When more than one speaker is used, the speakers are connected to each other in series when each is connected to be driven by an external second audio input signal instead of being driven by its respective amplifier. The advantage is that the speaker will be driven by an external amplifier with a higher power output than the internal power amplifier, so that the speaker will not be damaged when driven by a higher power external amplifier.

Description

Speaker arrangement and switching device therefor {LOUDSPEAKER ARRANGEMENT AND SWITCHING APPARATUS THEREFOR}

The present invention relates generally to an acoustic sound reproduction device, and more particularly to a speaker arrangement and a switching device therefor.

Television receivers with loudspeakers and audio sound systems with speakers are often placed in a common listening room, where the two listen to them simultaneously when each has its own program source. It can't work at the same time because it can't Thus, the utilization efficiency of each of the various speakers is reduced. For example, if the audio signal is a stereo signal reproduced in a multidirectional surround sound system such as the Dolbya.1 sound system, five speakers are used, where one of the speakers is the center speaker receiving the L + R signal. The television receiver has at least two speakers, for example if using an MTS stereo system. Thus, the space efficiency of the listening room is also reduced since both systems cannot be listened to at the same time when each has its own program source.

One such attempt to improve the utilization efficiency of several speakers and to improve the space efficiency of a listening room is presented in US Pat. No. 5,329,371.

An acoustic sound reproduction apparatus for a first audio signal, which is provided with an acoustic sound reproduction apparatus having an input terminal for a second audio signal, a selection switch and at least one speaker. At least one speaker is driven by a signal output from one of the first or second audio signals via a selection switch. As a result, the acoustic sound reproduction apparatus as the television receiver in the exemplary embodiment and the apparatus for providing the second audio signal as the surround sound audio system in the exemplary embodiment can use one speaker or a plurality of speakers in common. When an external audio signal is selected, at least one internal speaker becomes part of the external speaker arrangement for the surround sound system.

When more than one speaker is used, the speakers are connected to their respective amplifiers and in series with one another when connected by a selection switch to be driven by an external second audio signal. This allows the speaker to be driven by an external amplifier having a higher power output than the internal power amplifier, so that the speaker will not be damaged when driven by this higher power external amplifier. US Patent No. 4,146,745 discloses a speaker connected in series.

1 is a block diagram of a switch / speaker arrangement in accordance with an aspect of the present invention.

<Explanation of symbols for the main parts of the drawings>

10: television receiver 12: audio signal playback device

16: selection switch 18: amplifier

20: external input terminal 22, 34: output lead

The figure shows a block diagram of a switch / speaker arrangement of an acoustic signal reproducing apparatus according to an aspect of the present invention. The acoustic signal reproducing system of the present invention includes an audio signal reproducing apparatus 12 including a speaker 14 and a television receiver 10.

The device 12 includes a selector switch 16, an amplifier 18, an external input terminal 20, and an amplifier output terminal 27 that connects each amplifier output signal to each output lead 22, 34. Have The audio signal is supplied to the input terminal 23 of each amplifier 18, and each output terminal 27 is connected to each fixed terminal 24 of the selection switch 16. The conductive wire 22 connected to each speaker 14 is connected to the fixed terminal 25 of the switch 16. The signal at the external input terminal 20 is connected to the fixed terminal (s) 26 of the selector switch 16. The movable contact 28 may be moved to position "A" to select to internally drive each speaker 14 from the amplifier 18 via the output signal leads 22, 34. The speaker 14 is driven from a signal that can be obtained at the external input terminal 20 when the movable contact 28 is moved to position "B".

In an exemplary embodiment, an external audio signal reproducing apparatus that may be connected to terminal 20 is a surround sound system having a center speaker terminal for connecting to a speaker to receive a central L + R signal. This central speaker is located between the left and right front stereo speakers, for example, the speaker units of the surround sound system are typically front right position (FR), front left position (FL), and front, respectively, in a manner known in the art. The center position FC, the surround right position SR, and the surround left position SL are respectively disposed. However, it is also contemplated that the speaker (s) 14 may be used in place of any speaker in that surround sound system or any other speaker of any other type of sound system depending on the signal provided to the terminal 20. It is within the matter. In addition, since the television receiver has a stereo auxiliary audio input terminal 40, the television receiver is stereo to a stereo signal connected to this auxiliary input terminal 40 when the movable contact 28 is switched in the direction "A". It can provide an expansion effect (not shown).

Thus, the speaker 14, which can be connected to the external input terminal 20 of the television receiver 10 at the switch position “B”, is such that the speaker system 14 is shared by both the television receiver 10 and the external program source. To be used. The speaker system 14 has at least one speaker unit, and in the exemplary embodiment has two speakers, because the television receiver 10 is a stereo sound receiver. If the audio signal is provided by a surround sound audio system, the speaker system 14 may operate as a front center speaker FC as discussed above.

When two or more speakers 14 are disconnected from their respective amplifiers 18 and connected to the terminal 20 by a switch 16, the speakers are connected in series with each other, ie their impedance is added. Thus, for an external power amplifier with a transformerless output (almost all current audio power amplifiers are in this case), the power output is halved because the load impedance is doubled. The advantage is that the speaker is powered by an external power amplifier rated at a higher power output than each power amplifier 18 so that the speaker is not damaged by exposure to such higher power. Will have improved performance. The advantage is that the speaker's power rating only needs to match the power output of their respective amplifiers 18, thus allowing the use of low cost speakers.

Although the amplifiers 18 are the same because they are inside the same IC, it is within the consideration of the present invention that the amplifiers 18 may have different output powers and may be more than two. Furthermore, although this embodiment shows one input terminal 20, it can be used for a plurality of external amplifiers in which the plurality of input terminals need not have the same output power. Obviously, in that case, the switch 16 would change accordingly.

When the switch 16 is in the "center" position, ie switched to the position "B", the speaker 14 no longer loads each amplifier 18. Thus, as soon as the switch to the "center" position of the switch 16, the muting circuit 30 is activated by the switch 16. The muting circuit 30 is activated in response to connecting the output line 34 of the amplifier 18 from the switch terminal 38 to the input line 36 of the muting circuit 30. The muting circuit 30 applies a component connected to voltage and / or ground (not shown) to the muting pin 32 of the integrated circuit 33 to mute the integrated circuit in a manner known in the art or to place it in standby mode. do.

The amplifier 18 is part of the TDA7490 integrated circuit manufactured by STMicroelectronics of Geneva, Switzerland, and is a 25W stereo Class D amplifier. The power supply, oscillator and high frequency output filter are not shown in the figures and do not form any part of the present invention.

Switch 16 is a break-before-make slide switch, but any other suitable switch may be used, such as a toggle switch, repeater, for example.

As described above, the present invention generally has the effect of preventing the speaker from being damaged when driven by a higher power external amplifier in an acoustic sound reproduction device, more particularly in a speaker arrangement and a switching device therefor.

Claims (8)

In the device 16 for switching a plurality of speakers 14 between amplifiers 18 having various power outputs, First means for connecting the plurality of speakers 14 to a first plurality of power amplifiers 18 having a first power output; Second means for connecting the plurality of speakers (14) to at least one of a second power amplifier (18) each having a second power output greater than the first power output; Means for changing the circuit configuration of the plurality of speakers 14 in accordance with the power output of the amplifier 18 to which the plurality of speakers 14 are connected, A plurality of speaker switching device, characterized in. In the device (16) for switching a plurality of speakers (14) between amplifiers (18), First means for connecting the plurality of speakers 14 to the first plurality of power amplifiers 18; Second means for connecting the plurality of speakers (14) to at least one of a second power amplifier (18); Means for changing the circuit configuration of the plurality of speakers 14 in accordance with the power output of the amplifier 18 to which the plurality of speakers 14 are connected, A plurality of speaker switching device, characterized in. In the apparatus for switching a plurality of speakers 14 between amplifiers 18, First means for connecting the plurality of speakers (14) to at least one of the first plurality of power amplifiers (18) having a first power output; Second means for connecting the plurality of speakers (14) to at least one of a second power amplifier (18) having a second power output; Means for changing the circuit configuration of the plurality of speakers 14 in accordance with the power output of the amplifier 18 to which the plurality of speakers 14 are connected, A plurality of speaker switching device, characterized in. 4. The plurality of power supplies according to claim 3, characterized in that the first power output and the second power output are different from each other, the power amplifier 18 is at least one and the second power amplifier 18 is at least one. Speaker switching device. 4. The plurality of speaker switching devices of claim 3, wherein the second power output is greater than the first power output. In the device (16) for switching a plurality of speakers (14) between amplifiers (18), First means for connecting the plurality of speakers (14) in the first circuit configuration to at least one of the first plurality of power amplifiers (18) having a first power output; Second means for connecting the plurality of speakers 14 in a second circuit configuration to at least one of the second power amplifiers 18 having a second power output, A plurality of speaker switching device, characterized in. 7. A plurality of speaker switching devices according to claim 6, characterized in that the device is a television receiver (10). 7. The power supply of claim 6, wherein the individual speakers 14 are rated with a predetermined power, wherein each of the plurality of first power outputs is not the same and the predetermined power rating of the individual speaker 14 Or less than, wherein each of the plurality of second power outputs is not the same and is greater than a predetermined power rating of the individual speaker (14).