FR3014280A1 - ACOUSTIC SPEAKER, SOUND SYSTEM COMPRISING AT LEAST ONE SUCH ENCLOSURE AND TESTING SYSTEM FOR A SET OF ACOUSTIC SPEAKERS - Google Patents

Abstract

Acoustic speaker (EA) comprising a housing (CE) carrying at least one speaker (HP), characterized in that it is equipped with a monitoring device (DS) comprising: at least one vibration sensor (CV), for generating an electrical signal (SE) representative of a sound (VA) emitted by said one or a said speaker; and a transmission device (TSS) of a signal (SS) representative of said signal generated by said vibration sensor. A sound system comprising: at least one such acoustic speaker; a receiver, for receiving the signal (s) (SS) emitted by the transmitter (s) of the one or more monitoring devices of said or each said acoustic enclosure; and a data processing device for determining a state of operation of said or each said acoustic enclosure from the signal or signals received by said or each said receiver. Remote monitoring system for a set of loudspeakers, comprising at least one such monitoring device (DS), such a receiver (RSS) and such a data processing device.

Description

ACOUSTIC SPEAKER, SOUND SYSTEM COMPRISING AT LEAST ONE SUCH ENCLOSURE AND TESTING SYSTEM FOR A SET OF ACOUSTIC SPEAKERS The invention relates to an acoustic enclosure equipped with a monitoring device for remotely verifying its operation. The invention also relates to a sound system comprising at least one such enclosure, as well as a remote monitoring system for a set of speakers.

The invention applies mainly, but not restrictively, to the sound of theaters and cinemas. In a conventional manner, the loudspeakers are distributed in a room or on the walls thereof. In the example of a movie theater, some speakers can be placed behind the screen, hanging high, often several meters above the ground. FIG. 1A illustrates a so-called "7.1" sound system comprising seven speakers or sets of speakers EA (four on the side walls, three behind the projection screen EP), plus a so-called "sub-woofer" speaker SW intended for the reproduction of bass sounds.

The general trend is towards increasingly complex PA systems, including a large number of independently controlled loudspeakers for three-dimensional sound effects to better reproduce "natural" sound sensations during projection. movies in the cinema or in a home cinema. Amphitheatres, conference rooms or large projection rooms can thus have several dozen speakers fixed in height, on the walls or on the ceiling of the room, in order to restore the soundscape of the projected film to the best of the room. . Figure 1B illustrates a PA system of this type, consisting of 16 EA speakers hung from the ceiling, plus the "sub-woofer" SW. These speakers are controlled, individually or in groups, from an SC control room usually located at the back of the projection room. Control is made possible by electronic equipment known as "amplified controllers". An amplified controller typically comprises a digital signal processing processor, or "DSP", receiving two or more input signals and generating output signals; digital / analog and analog / digital converters for interfacing this processor with analog input and output signals; power amplifiers for the analog output signals; an adaptive diet; a network card and a user interface; all controlled by a central processing unit (or "CPU").

See the document "LA4 amplified controller, user manual, version 4.0", from L-Acoustics, downloadable from www.lacoustics.com. The installation of a large number of speakers, if it allows a faithful reproduction of sound in "3D", presents a number of disadvantages for the operator of the sound system, and this despite the availability of equipment sophisticated such as the aforementioned amplified controllers: - its complexity of installation by the number of speakers to manage and identify from the control room; difficulty in knowing whether the acoustic system in use is operating at its optimum, or whether one or more speakers are malfunctioning; - the time and material costs related to the periodic verification of loudspeakers and their effective functioning.

The invention aims to overcome in whole or in part at least one of the aforementioned drawbacks of the prior art. More specifically, the invention aims to allow verification, remotely and in real time, the operation of the speakers of a sound system, whatever the complexity. Optionally, or alternatively, the invention aims to enable remote switching on / off of active loudspeakers, that is to say comprising an amplifier.

An object of the invention, making it possible to achieve at least one of these objects, is an acoustic enclosure comprising a box carrying at least one loudspeaker, characterized in that it is equipped with a monitoring device comprising: at least a vibration sensor, for generating an electrical signal representative of a sound emitted by said one or a said speaker; and a device for transmitting a signal representative of said signal generated by said vibration sensor. According to different embodiments of such a chamber: - Said or at least one said vibration sensor may be integral with a wall of said box. - Said transmission device may be a wireless transmitter. Said monitoring device may also comprise a signal processing module connected to receive the signal generated by said vibration sensor as input and to supply an input to said transmission device with a processed signal to be transmitted. - Said monitoring device may also include a battery pack. Said monitoring device can be electrically connected to a supply line of at least one said loudspeaker in order to be powered in turn. - Said monitoring device may comprise a housing attached to a wall of said housing, containing at least said or a said vibration sensor and said transmission device. Said enclosure may also comprise at least one amplifier connected to said at least one said loudspeaker, an electrical cut-off device, arranged on a supply line of said amplifier, and a receiver for a control signal of said amplifier. Said receiver for a control signal of said amplifier may be a wireless receiver. Another object of the invention is a sound system comprising: at least one loudspeaker according to one of the preceding claims; at least one receiver, for receiving the signal (s) emitted by the transmitter (s) of the one or more monitoring devices of said or each said acoustic enclosure; and a data processing device for determining a state of operation of said or each said acoustic enclosure from the signal or signals received by said or each said receiver. According to various embodiments of such a system: the system may also comprise a device for displaying said operating state or states. At least one said acoustic enclosure may also comprise at least one amplifier connected to said one or a said loudspeaker, at least one electrical cut-off device, arranged on a supply line of said amplifier, and at least one receiver for a signal controlling said or a said cutoff device; said system also comprising a transmitter for transmitting to said receiver a said control signal. Yet another object of the invention is a remote monitoring system for a set of loudspeakers, comprising: at least one monitoring device of an acoustic enclosure, comprising at least one vibration sensor, for generating a signal representative of a sound from said speaker or a speaker and a signal transmission device representative of said signal generated by said vibration sensor; at least one receiver, for receiving the signal or signals emitted by the transmitter or transmitters of said or each said monitoring device; and a data processing device for determining an operating state of said one or each said acoustic enclosure from the signal or signals received by said one or each said receiver. According to various embodiments of such a system: said at least one said monitoring device can comprise at least one housing that can be fixed to a wall of a box 30 of an acoustic enclosure, containing at least said one or a said vibration sensor and said or a said transmission device. The system may also comprise: at least one electrical cut-off device that can be arranged on a supply line of an amplifier of an active acoustic enclosure; at least one receiver for a control signal of said one or said cut-off device; and at least one transmission device, for transmitting to said receiver a said control signal. Other characteristics, details and advantages of the invention will emerge on reading the description made with reference to the appended drawings given by way of example and which represent, respectively: FIG. 2, an overview of a acoustic enclosure according to one aspect of the invention, equipped with a device for monitoring its operation; FIG. 3 is a block diagram of a first embodiment of such an acoustic enclosure; FIG. 4 is a block diagram of a second embodiment of such an acoustic loudspeaker; and FIG. 5, a block diagram of a control station communicating with one or more loudspeakers according to the invention. Figure 2 shows an acoustic loudspeaker EA according to one embodiment of the invention. In a conventional manner, such a chamber comprises a CE-shaped box parallelepiped CE having a front face which carries one or more speakers HP (3 in the example of the figure). The box may also contain an audio amplifier (not shown) amplifying the signals provided to the speakers; we are talking about an "active enclosure". The chamber of FIG. 1 differs from an enclosure according to the prior art in that it also comprises a monitoring device DS whose structure and operation will be described with the help of FIG. is a detailed sectional view of the enclosure of FIG. 2, showing in particular a portion of the front wall PCE of the box CE, a loudspeaker HP attached to said wall and the monitoring device DS, contained in a removable housing B attached to an outer face of said front wall PCE. It should be noted that, as a variant, the device DS could be integrated into the enclosure instead of being attached via the removable housing B; Moreover, it could be in contact with another wall of the box, or with another element of the enclosure. However, the embodiment illustrated in the figure is advantageous because a conventional commercial speaker can be converted into an enclosure according to the invention simply by adding the device DS. This device comprises a CV vibration sensor in contact with the wall PCE. When an audio signal SA is input to the speaker HP, the latter generates an acoustic vibration (wave) VA that propagates in the air, and a mechanical vibration that propagates along the wall PCE. This vibration is detected by the sensor CV, which generates in response a signal SE, generally of an electrical nature. This signal is processed (for example: amplified, filtered, thresholded, sampled, digitized) by a processing module - typically an electronic circuit - then the processed signal ST is input to a transmission device TSS which transmits it - for example via an ANT antenna - in the form of an SS monitoring signal. All these elements are powered by a BAT battery. Remote detection of the SS signal makes it possible to check the correct operation of the enclosure. Indeed, in case of malfunction the VM mechanical vibrations would be absent, or have spectral characteristics or intensity different from those expected. The vibration sensor may be of any known type, for example piezoelectric. The data processing module may be limited to a conditioning of the signal from the sensor (or even be absent), in which case the monitoring signal SS essentially reproduces the mechanical vibration VM, the diagnosis of the operation of the enclosure being carried out by the receiver of this signal. Or the processing module itself can perform a diagnosis, and transmit its result via the signal SS. The TSS transmission device is preferably a wireless, radio or infrared transmitter. It can work, for example, according to the WiFi, Bluetooth or Zigbee standard (the latter two standards are particularly low in energy consumption, which is advantageous for a battery power supply). However, wired transmission can also be envisaged; for example, the signal SS can be transmitted by the same link which carries the audio signal SA, in particular if the latter is a digital link. Figure 4 relates to a variant, particularly well suited to the case of an active speaker, comprising an AMP audio amplifier providing an amplified audio signal to the HP speaker and powered by a power line LA. In this variant, the active components (processing module MT, transmission device TSS) of the monitoring device DS are fed via the line LA, and no longer by a battery (a battery, recharged via the link LA, could nevertheless be present to ensure the operation of the device even in the absence of power supply of the amplifier).

In the example of FIG. 4, an electric breaking device - or controlled switch - DC is arranged on the power supply line LA. This device is controlled by a control signal STC received by an RSC receiver via an antenna ANT '(the receiver RSC, and preferably also the monitoring device DS, are supplied via a bypass located upstream of the DC cut-off device) . This allows the AMP amplifier to be switched on and off remotely. The DC electrical breaking device may be or comprise one or more electromagnetic relays and / or one or more power semiconductor devices (transistors, thyristors, etc.), possibly equipped with electronic control circuits. Figure 4 shows two separate antennas ANT and ANT ', but they could actually coincide. Moreover, like the TSS transmission device, the RSC receiver could use an infrared or even wired technology. The ANT '/ RSC / DC package forms a remote ignition and extinguishing module that could be combined with a battery powered DS monitoring device. This module could be located inside the housing B, in an independent housing or without a housing. This module could even be used in the absence of the monitoring device. A sound system according to the invention comprises one or more enclosures EA, arranged for example as illustrated by FIGS. 1A and 1B, equipped with respective monitoring devices DS communicating with at least one control station that can be located in a control room SC. As illustrated in FIG. 5, such a control station comprises one or more RSS receivers for the SS surveillance signals transmitted by the DS devices of the different speakers and / or one or more TSC transmitters for control signals of the DC cut-off devices. different speakers. Known techniques are used to distinguish signals received from or intended for the different loudspeakers: use of carriers at different frequencies, orthogonal spreading sequences, transmission of data packets with headers containing source codes and destination, etc. A DTD data processing device, which may be a conveniently programmed computer, receives the SS signals picked up by the RSS receiver (s), uses them to determine a state of health of each speaker of the sound system and displays it under an intelligible format by a user by means of a display device DA (screen or set of indicator lights). The same or another data processing device can generate the STC signals for turning on and off the active speakers remotely. According to an advantageous embodiment, the interface with the user can be provided by a web browser.

A monitoring station of the type of FIG. 5 and a set of monitoring devices DS form a remote monitoring system according to one aspect of the invention. If the monitoring device or devices are of the removable type (see FIG. 3), such a remote monitoring system may be in the form of a "kit" for converting a conventional sound system into a system according to the invention. without having to replace the speakers.

Claims (15)

REVENDICATIONS1. Acoustic speaker (EA) comprising a housing (CE) carrying at least one speaker (HP), characterized in that it is equipped with a monitoring device (DS) comprising: - at least one vibration sensor (CV) to generate an electrical signal (SE) representative of a sound (VA) emitted by said one or a said speaker; and a transmission device (TSS) of a signal (SS) representative of said signal generated by said vibration sensor. 2. acoustic chamber according to claim 1 wherein said or at least one said vibration sensor is integral with a wall (PCE) of said box. 3. acoustic chamber according to one of the preceding claims wherein said transmission device is a wireless transmitter. 4. acoustic chamber according to one of the preceding claims wherein said monitoring device also comprises a signal processing module (MT) connected to receive as input the signal (SE) generated by said vibration sensor and to provide input to said transmission device a processed signal (ST) to be transmitted. 5. acoustic chamber according to one of the preceding claims wherein said monitoring device also comprises a battery pack (BAT). 6. acoustic chamber according to one of claims 1 to 4 wherein said monitoring device is electrically connected to a supply line (AL) of at least one said speaker to be fed in turn. 7. acoustic chamber according to one of the preceding claims wherein said monitoring device comprises a housing (B) attached to a wall of said housing, containing at least said one or a said vibration sensor and said transmission device. 8. acoustic chamber according to one of the preceding claims also comprising at least one amplifier (AMP) connected to said at least one said speaker, an electrical cut-off device (DC), arranged on a supply line of said amplifier, and a receiver (RSC) for a control signal (STC) of said amplifier. 9. The acoustic chamber of claim 8 wherein said receiver for a control signal of said amplifier is a wireless receiver. 10. A sound system comprising: - at least one loudspeaker (EA) according to one of the preceding claims; At least one receiver (RSS), for receiving the signal (s) (SS) emitted by the transmitter (s) of the one or more monitoring devices of said or each said acoustic enclosure; and a data processing device (DTD) for determining a state of operation of said or said acoustic enclosure from the signal (s) received by said or each said receiver. 11. PA system according to claim 10 also comprising a display device (DA) of said operating state or states. 30 12. PA system according to one of claims 10 and 11 wherein at least one said acoustic chamber also comprises at least one amplifier (AMP) connected to said or said speaker, at least one electrical cut-off device (DC) , arranged on a supply line (AL) of said amplifier, and at least one receiver (RSC) for a control signal of said one or a said cut-off device; said system also comprising a transmitter (TSC) for transmitting to said receiver a said control signal (STC). 13. Remote monitoring system for a set of loudspeakers, comprising: - at least one monitoring device (DS) of an acoustic loudspeaker (EA), comprising at least one vibration sensor (CV), for generating a representative signal a sound emitted by said one or a said speaker and a transmission device (TTS) of a signal (SS) representative of said signal generated by said vibration sensor; at least one receiver (RSS), for receiving the signal (s) (SS) transmitted by the transmitter or transmitters of said or each said monitoring device; and a data processing device (DTD) for determining an operating state of said or each said acoustic enclosure from the signal or signals received by said or each said receiver. Remote monitoring system according to claim 13, in which the said at least one monitoring device comprises at least one housing (B) which can be fixed to a wall of a chamber of an acoustic enclosure, containing at least the said one or a said vibration sensor and said or a said transmission device. 15. Remote monitoring system according to one of claims 13 or 14 also comprising 30 - at least one electrical switching device (DC) can be arranged on a power line (AL) of an amplifier of an active acoustic speaker at least one receiver (RSC) for a control signal (STC) of said one or a said cut-off device; and at least one transmission device (TSC) for transmitting to said receiver a said control signal.