DE102007014372B4 - Audio signal processing system and motor vehicle - Google Patents

Abstract

Audio signal processing system
with a first input for a plus and a minus path signal of a first balanced main signal (HS1),
with a second input for a plus and a minus path signal of a second balanced main signal (HS2),
with a third input for a plus and a minus path signal of a symmetrical additional signal (ZS),
with a correction element (1) by which the main signals (HS1, HS2) and the additional signal (ZS) are coupled to one another in such a way that
the plus-path signal of the first main signal (HS1) is added to the plus-path signal of the additional signal (ZS),
that the minus-path signal of the first main signal (HS1) is added to the minus-path signal of the additional signal (ZS),
the plus-path signal of the second main signal (HS2) is added to the minus-path signal of the additional signal (ZS), and
that the minus-path signal of the second main signal (HS2) is added to the plus-path signal of the additional signal (ZS),
with a mixing element (2) by which the main signals (HS1, HS2) and the additional signal corrected by the correction element (1) are coupled to one another in such a way that
that the plus path signal of the corrected additional signal is added to the plus path signal and the minus path signal of the first main signal (HS1), and
that the minus-path signal of the corrected additional signal is added to the plus-path signal and to the minus-path signal of the second main signal (HS2),
with a two output stage amplifier (V1, V2), in particular bridge output stage amplifier, comprehensive amplifier element through which the mixed by the mixing member (2) mixed main signals are amplified.

Description

The invention relates to an audio signal processing system and a motor vehicle.

From the WO 03/094572 A1 For example, a three speaker loudspeaker system comprising first and second amplifiers each amplifying a channel of an audio signal, the outputs of the amplifiers being in anti-phase, respectively connected to the inputs of the first and second loudspeakers. The outputs of the amplifiers are also connected to the inputs of the third loudspeaker, bridge amplifiers being provided as amplifiers.

From the DE3416494 A1 a display device for audio signals is known in which a sum signal is generated from the individual signals.

As a result, in the case of an arrangement having two bridge output stages, a common-mode signal is impressed in addition to the existing difference signal of each output stage. The common-mode signal of one output stage is in phase opposition to the common-mode signal of the other output stage. This allows you to control a third speaker (usually a bass speaker) with an independent signal.

This can be reduced due to the savings of components (power amplifier or external crossovers) costs.

The invention is based on the object of providing an economical technical teaching in order, in particular in a vehicle, to amplify at least three, in particular individually influenceable, audio signals for at least three loudspeakers.

This object is solved by the features of the main claim. Advantageous developments of the invention can be found in the dependent claims.

Accordingly, the invention is also based on the idea of amplifying three different audio signals (two main signals and one additional signal) by only two output stage amplifiers by appropriately connecting the plus path signal and the minus path signal of the additional signal in a mixer to the Be amplified and amplified together with these.

The invention is now intended in particular to ensure that different audio signals can each be modified individually and / or independently of one another before amplification, for example by fading or equalizing, without this modification having an influence on various audio signals due to the shared use of an output stage amplifier has a different audio signal.

To this end, the invention provides for a correction element to be connected upstream of the mixing element, by means of which the main signals and the additional signal are suitably coupled to each other before amplification.

Preferably, an audio signal processing system comprises a first input for a plus and a minus path signal of a first balanced main signal, a second input for a plus and a minus path signal of a second balanced main signal and a third input for a plus and a minus path signal of a balanced additional signal.

A correction term is arranged such that the main signals and the additional signal are coupled to one another in such a way that the plus path signal of the first main signal is added to the plus path signal of the additional signal, that the minus path signal of the first main signal to minus Path signal of the additional signal is added, that the plus path signal of the second main signal is added to the minus path signal of the additional signal, and that the minus path signal of the second main signal adds to the plus path signal of the additional signal becomes.

A mixer is arranged such that the main signals and the additional signal corrected by the correction term are coupled together such that the plus path signal of the corrected additional signal is added to the plus path signal and the minus path signal of the first main signal, and summing the minus path signal of the corrected auxiliary signal to the plus path signal and the minus path signal of the second main signal.

Finally, the main signals mixed by the mixing element are amplified by means of one or two output stage amplifiers, in particular bridge output stage amplifiers, comprehensive amplifier elements.

By the correction term, for example, a modification of a first main signal results in a corresponding, in particular attenuated, modification of the second main signal, wherein the modification of the first main signal is effective with respect to the first loudspeaker, the modification of the second main signal with respect to the second loudspeaker is ineffective, and the two modifications are ineffective with respect to the third loudspeaker.

For the purpose of decoupling modifications of an audio signal from other audio signals, it is particularly preferred that the correction element is set up in such a way that the plus-path signals and the minus path signals of the first and second main signals are attenuated prior to addition to the plus path signal or minus path signal of the additional signal, in particular by 6 dB.

Advantageously, the amplifier element comprises four single-ended output stage amplifiers, which are operated in pairs as bridge output stage amplifiers, the plus path signal and the minus path signal of the first mixed main signal being supplied to the first bridge output stage, and the plus path Signal and the minus path signal of the second mixed main signal of the second bridge output stage are supplied.

Preferably, it is provided:
a first speaker supplied with the positive path signal output by the first output amplifier and the minus path signal output by the first output amplifier;
a second loudspeaker to which the positive path signal output by the second output stage amplifier and the minus path signal output by the second output stage amplifier are supplied, and
a third speaker to which the positive path signal output by the first output stage amplifier and the plus path signal output by the second output stage amplifier are supplied.

The first loudspeaker is preferably a part of a front loudspeaker group of a vehicle, the second loudspeaker part of a rear loudspeaker group of a vehicle and / or the third loudspeaker part of a bass speaker group of a vehicle.

The first main signal is preferably associated with or provided for the first loudspeaker, the second main signal is preferably associated with or provided for the second loudspeaker, and the additional signal is preferably associated with or provided for the bass loudspeaker.

Preferably, the first main signal, the second main signal and / or the additional signal is an audio signal output from an audio source and modified by a modifier such as a fader, balance control or equalizer. The first main signal, the second main signal and / or the additional signal may differ, for example, with regard to the frequency and / or their determination with regard to a loudspeaker to be controlled.

In addition to the aforementioned loudspeakers and components, the audio signal processing system may of course comprise further components, such as amplifiers, loudspeakers, filters or signal processing units, whose structure and mode of operation are known per se to those skilled in the art.

In the context of the invention is also a motor vehicle with at least two audio signal processing systems according to the invention, wherein in particular one is provided for the preferred sonication of the left half of the vehicle and a preferred sonication of the right half of the vehicle.

In the following, the invention is explained in more detail by means of examples with reference to the following figures:

1 shows a block diagram with a waveform and a signal level behavior when driving the first main channel;

2 shows a schematic diagram with a waveform and a signal level behavior when driving the second main channel;

3 shows a block diagram with a waveform and a signal level behavior when driving all three channels.

1 shows an audio system to which an input signal a symmetrical first main signal HS1, which is provided for the front speaker VL, and a balanced second main signal HS2 which is provided for the rear loudspeaker HL, and an additional signal ZS, which is provided for a central bass loudspeaker supplied can be.

In this example, the three audio signals mentioned are modified audio signals.

In order to explain the invention, the following first embodiment assumes that the three audio signals are modified in such a way as to bring about a complete fading to the front, that is to say in the first embodiment. H. it should only be on the front speakers a signal output. Accordingly, of the entire input signal, only the incoming first main signal is not equal to zero and is shown simplified as a sine period.

Through a correction element 1 the plus-path signal of the first main signal HS1 is added to the plus-path signal of the additional signal, the minus-path signal of the first main signal HS1 adds to the minus-path signal of the additional signal ZS, the plus-path signal of the second Main signal HS2 adds to the minus path signal of the additional signal ZS, and adds the minus path signal of the second main signal HS2 to the positive path signal of the additional signal ZS. In this case, the plus-path signals and the minus-path signals of the first and second main signals are attenuated before addition to the plus-path signal or minus-path signal of the additional signal, in particular by 6 dB.

This results in the illustrated correction signal.

Through a mixing element 2 the plus path signal of the corrected auxiliary signal is added to the plus path signal and to the minus path signal of the first main signal, and the minus path signal of the corrected additional signal to the plus path signal and to the minus path signal. Signal of the second main signal added.

The modification, correction and mixing of the audio signals can be put into practice by a suitably equipped digital signal processor.

By an amplifier element with two power amplifiers V1, V2, in particular bridge power amplifiers, the through the mixing element 2 amplified mixed main signals.

In this example, the amplifier element comprises four single-ended output stage amplifiers, which are operated in pairs in the output as bridge output stage amplifier V1, the plus path signal and the minus path signal of the first mixed main signal being fed to the first bridge output stage and the positive Path signal and the minus path signal of the second mixed main signal of the second bridge amplifier V2 is supplied.

This results in the illustrated output signals.

A front speaker VL is supplied with the positive path signal output by the first output amplifier V1 and the minus path signal output by the first output amplifier V1. A rear loudspeaker HL is supplied with the plus path signal output by the second output stage amplifier V2 and the minus path signal output by the second output stage amplifier V2. A bass speaker is supplied with the plus-path signal output by the first output amplifier V1 and the plus-path signal output by the second output amplifier V2.

It turns out that as a result only at the front loudspeaker VL an audio signal is output, which also corresponds to the incoming first main signal HS1. At the other two speakers HL, ZBL as desired no audio signal is output, since no corresponding incoming audio signal is present.

2 shows the audio system 1 , In this example, it is assumed that the three audio signals are modified in such a way that a complete fading to the rear is effected, that is to say that a signal is to be output only at the rear loudspeaker. Accordingly, of the entire input signal, only the incoming second main signal is not equal to zero and is shown simplified as a sine period. Like reference numerals designate corresponding elements throughout the several figures.

Again, the resulting correction signals and output signals are shown. As a result, it can be seen again that only at the rear loudspeaker HL an audio signal is output, which also corresponds to the incoming second main signal HS2. At the two other speakers VL, ZBL as desired, no audio signal is output, since no corresponding incoming audio signal is present.

3 shows the audio system 1 In this example, it is assumed that the three audio signals are modified in such a way that a neutral fading is effected, ie equal weighted signals are to be output at the front loudspeaker and at the rear loudspeaker. Accordingly, of the total input signal, the incoming first and second main signals are nonzero and simplified as a sine period.

Again, the resulting correction signals and output signals are shown. As a result, it again appears that audio signals are output only at the front loudspeaker VL and at the rear loudspeaker HL, which also correspond to the incoming first HS1 or second main signal HS2. On the other speaker ZBL as desired no audio signal is output, since no corresponding incoming audio signal is present.

The correction element has the effect that, despite the effect in the mixing element of the additional signal, a main signal coupled to a path of the additional signal can be amplified on the modified first main signal and on the modified second main signal, so that after the common amplification the main signals and the additional signal again are easily separable and are no longer affected by another signal.

Claims (10)

Audio signal processing system having a first input for a plus and a minus path signal of a first balanced main signal (HS1), with a second input for a plus and a minus path signal of a second balanced main signal (HS2), with a third Input for a plus and a minus path signal of a balanced additional signal (ZS), with a correction element ( 1 ), by which the main signals (HS1, HS2) and the additional signal (ZS) are coupled together in such a way that the plus-path signal of the first main signal (HS1) is added to the plus-path signal of the additional signal (ZS) the minus-path signal of the first main signal (HS1) is added to the minus-path signal of the additional signal (ZS), that the plus-path signal of the second main signal (HS2) is added to the minus-path signal of the additional signal (ZS) is added, and that the minus-path signal of the second main signal (HS2) is added to the plus-path signal of the additional signal (ZS), with a mixing element ( 2 ), by which the main signals (HS1, HS2) and by the correction element ( 1 ) are coupled together such that the plus path signal of the corrected additional signal is added to the plus path signal and the minus path signal of the first main signal (HS1) and that the minus path signal of the corrected one Additional signal to the plus-path signal and the minus-path signal of the second main signal (HS2) is added, with a two output stage amplifier (V1, V2), in particular bridge power amplifier, comprehensive amplifier element through which the by the mixing element ( 2 ) mixed main signals are amplified. An audio signal processing system according to claim 1, wherein the correction term ( 1 ) is arranged such that the plus-path signals and the minus-path signals of the first and second main signal (HS1, HS2) before addition to the plus-path signal or minus-path signal of the additional signal, in particular 6 dB, be attenuated. Audio signal processing system according to one of the preceding claims, in which the amplifier element (V1, V2) comprises four single-ended power amplifiers which are operated in pairs as bridge output stage amplifiers, wherein the plus-path signal and the minus-path signal of the first mixed Main signal of the first bridge output stage is supplied and the plus-path signal and the minus-path signal of the second mixed main signal of the second bridge output stage is supplied Audio signal processing system according to one of the preceding claims, with a first loudspeaker (VL) to which the plus-path signal output by the first output stage amplifier and the minus path signal output by the first output stage amplifier are supplied, to a second loudspeaker (HL) to which the one output by the second output stage amplifier Plus path signal and the output by the second output amplifier minus path signal is supplied, and with a third loudspeaker (ZBL) to which the plus-path signal output by the first output stage amplifier and the plus-path signal output by the second output stage amplifier are supplied. An audio signal processing system according to any one of the preceding claims, wherein the first loudspeaker (VL) is part of a front loudspeaker of a vehicle. An audio signal processing system according to any one of the preceding claims, wherein the second loudspeaker (HL) is part of a rear loudspeaker of a vehicle. Audio signal processing system according to one of the preceding claims, in which the third loudspeaker (ZBL) is part of a bass loudspeaker of a vehicle. Audio signal processing system according to one of the preceding claims, in which the first main signal (HS1) is assigned to the first loudspeaker (VL), in which the second main signal (HS2) is assigned to the second loudspeaker (HL), and in which the additional signal (ZL) is assigned to the bass loudspeaker (ZBL). Audio signal processing system according to one of the preceding claims, in which the first main signal (HS1), the second main signal (HS2) and / or the additional signal (ZS) are output by an audio source and by a modification element, such as a fader, balance control or equalizer, modified audio signal is. Motor vehicle with at least two audio signal processing systems according to one of the preceding claims.

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