An audio broadcasting device and a network broadcasting system

Abstract

The utility model discloses an audio frequency broadcast device and network broadcast system, include: main control module, power amplifier module, power switch module and loudspeaker module, the output of main control module is connected to the first input of power switch module, and the output of power switch module is connected to the input of power amplifier module, and the output of power amplifier module is connected to loudspeaker module, when the second input of power switch module is by POE power supply independent power supply, and the output power of power switch module is first power, when the second input of power switch module is by direct current power supply independent power supply, and the output power of power switch module is second power, when the second input of power switch module is by direct current power supply and POE power supply combination power supply, and the output power of power switch module is second power. This audio frequency broadcast device is favorable to improve audio frequency broadcast effect. The utility model relates to electronic circuit technical field.

Description

Technical Field

[0001] This utility model relates to the field of electronic circuit technology, and in particular to an audio broadcasting device and a network broadcasting system. Background Technology

[0002] A network broadcasting system is a system that plays media audio sources through network control terminals. It is highly valued by relevant personnel due to its wide range of applications (such as factories, schools, residential areas, buildings, etc.).

[0003] Currently, the relevant technology typically involves the network host transmitting media audio sources to the terminal via a PoE network cable in a network broadcasting system, while simultaneously supplying power to the terminal via the PoE network cable. However, due to the limited power supply of PoE, this method is prone to the phenomenon that the terminal's loudspeakers (such as horn speakers) continuously operate below their rated power, resulting in poor audio broadcasting quality.

[0004] Therefore, the problems with the relevant technologies still need to be solved and optimized. Utility Model Content

[0005] The purpose of this utility model is to solve, to a certain extent, the technical problems existing in the related technologies.

[0006] Therefore, one objective of this utility model is to provide an audio broadcasting device and a network broadcasting system, wherein the audio broadcasting device can automatically switch the output power according to different power supply methods, so that the speaker module of the audio broadcasting device can broadcast at normal operating power under DC power supply, which is beneficial to improving the audio broadcasting effect.

[0007] To achieve the above-mentioned technical objectives, on the one hand, this utility model embodiment provides an audio broadcasting device, including: a main control module, a power amplifier module, a power switching module, and a speaker module; The output terminal of the main control module is connected to the first input terminal of the power switching module, the output terminal of the power switching module is connected to the input terminal of the power amplifier module, and the output terminal of the power amplifier module is connected to the speaker module. The second input terminal of the power switching module is connected to an external POE power supply and / or DC power supply. When the second input terminal of the power switching module is independently powered by the POE power supply, the output power of the power switching module is the first power; when the second input terminal of the power switching module is independently powered by the DC power supply, the output power of the power switching module is the second power; when the second input terminal of the power switching module is powered by a combination of the DC power supply and the POE power supply, the output power of the power switching module is the second power, and the second power is greater than the first power.

[0008] In addition, an audio broadcasting device according to an embodiment of the present invention may also have the following additional technical features: Optionally, in one embodiment of this utility model, the main control module includes a network interface and a control chip; The network interface is connected to the input terminal of the control chip, and the output terminal of the control chip is connected to the power switching module.

[0009] Optionally, in one embodiment of the present invention, the power switching module includes a drive amplification unit, a power supply indication unit, an operational amplification unit, and a switching unit; The first input terminal of the drive amplification unit is connected to the output terminal of the main control module, and the first output terminal of the drive amplification unit is connected to the first input terminal of the switching unit. The output of the switching unit is connected to the driving amplification unit via the operational amplification unit, and the second output of the driving amplification unit is connected to the input of the power amplifier module. The input terminal of the power supply indicator unit is connected to a PoE power supply and / or a DC power supply, the first output terminal of the power supply indicator unit is connected to the second input terminal of the switching unit, and the second output terminal of the power supply indicator unit is connected to the third input terminal of the switching unit.

[0010] Optionally, in one embodiment of the present invention, the power supply indicator unit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a first diode, a second diode, a transistor, and a first capacitor; One end of the first resistor is connected to the DC power supply, and the other end of the first resistor is connected to the second input terminal of the switching unit; One end of the second resistor is connected to the POE power supply, and the other end of the second resistor is connected to the third input terminal of the switching unit; The anode of the first diode is connected to one end of the first resistor, the cathode of the first diode is connected to the cathode of the second diode, and the anode of the second diode is connected to one end of the second resistor; The collector of the transistor is connected to the other end of the second resistor, the base of the transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is connected to the other end of the first resistor. The emitter of the transistor is connected to one end of the first capacitor, one end of the third resistor is connected to one end of the first capacitor, the other end of the third resistor is connected to the other end of the first capacitor, one end of the fourth resistor is connected to the other end of the first capacitor, and one end of the first capacitor is grounded.

[0011] Optionally, in one embodiment of the present invention, the operational amplifier unit includes a second capacitor, a third capacitor, a fourth capacitor, a fifth resistor, a sixth resistor, and a seventh resistor; One end of the second capacitor is connected to the first output terminal of the switching unit, and the other end of the second capacitor is connected to one end of the fifth resistor, and the other end of the fifth resistor is connected to the second input terminal of the drive amplifier unit. One end of the third capacitor is connected to the second output terminal of the switching unit, one end of the third capacitor is connected to one end of the sixth resistor, and the other end of the sixth resistor is connected to the second output terminal of the driving amplifier unit via the seventh resistor; The second end of the drive amplifier unit is connected to the other end of the sixth resistor via the fourth capacitor, and the other end of the sixth resistor is connected to the other end of the fifth resistor.

[0012] Optionally, in one embodiment of the present invention, the switching unit includes a switching chip, and the output terminal of the switching chip is connected to the driving amplification unit via the operational amplification unit.

[0013] Optionally, in one embodiment of the present invention, the switching unit includes a switching chip, and the output terminal of the switching chip is connected to the driving amplification unit via the operational amplification unit.

[0014] Optionally, in one embodiment of the present invention, the driving amplification unit includes a first power amplifier chip, which is connected to the input terminal of the power amplifier module.

[0015] Optionally, in one embodiment of the present invention, the power amplifier module includes a second power amplifier chip, which is connected to the speaker module.

[0016] On the other hand, this utility model embodiment provides a network broadcasting system, including a network service host and the aforementioned audio broadcasting device, wherein the network service host is communicatively connected to the audio broadcasting device.

[0017] The advantages and beneficial effects of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this invention: This application discloses an audio broadcasting device and network broadcasting system, comprising: a main control module, a power amplifier module, a power switching module, and a speaker module; the output terminal of the main control module is connected to the first input terminal of the power switching module, the output terminal of the power switching module is connected to the input terminal of the power amplifier module, and the output terminal of the power amplifier module is connected to the speaker module; the second input terminal of the power switching module is externally connected to a PoE power supply and / or a DC power supply; when the second input terminal of the power switching module is independently powered by the PoE power supply, the output power of the power switching module is a first power; when the second input terminal of the power switching module is independently powered by the DC power supply, the output power of the power switching module is a second power; when the second input terminal of the power switching module is powered by a combination of the DC power supply and the PoE power supply, the output power of the power switching module is a second power, and the second power is greater than the first power. This audio broadcasting device automatically switches the output power according to the power supply method through the power switching module. Specifically, when the audio broadcasting device is powered by a DC power supply, the output power is controlled to be the second power, which allows the speaker module of the audio broadcasting device to broadcast at its normal operating power, thus improving the audio broadcasting effect. Attached Figure Description

[0018] The accompanying drawings are used to provide a further understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0019] Figure 1 A schematic diagram of the frame of an audio broadcasting device provided in one embodiment of the present invention; Figure 2 A schematic diagram of the overall circuit of a power switching module provided in one embodiment of this utility model; Figure 3 A circuit diagram of a power supply indicator unit provided in one embodiment of the present utility model; Figure 4 A circuit diagram of an operational amplifier unit provided in one embodiment of the present invention; Figure 5 A circuit schematic diagram of a switching unit provided in one embodiment of the present invention; Figure 6 A circuit diagram of a driving amplifier unit provided in one embodiment of the present invention; Figure 7 This is a circuit diagram of a power amplifier module provided as an embodiment of the present invention. Detailed Implementation

[0020] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0021] In the description of this utility model, it should be understood that the terms "length," "upper," "lower," "front," "rear," "left," "right," "top," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0022] Currently, the relevant technology typically involves the network host transmitting media audio sources to the terminal via a PoE network cable in a network broadcasting system, while simultaneously supplying power to the terminal via the PoE network cable. However, due to the limited power supply of PoE, the audio broadcasting effect is not good.

[0023] Specifically, in practical applications, the output power of common PoE switches on the market is about 30W at the output port, while the rated power of medium and high voltage horn speakers is usually greater than 50W. After deducting the heat loss during power transmission, the driving power of the horn speaker reaching the terminal is often only 20W. That is, PoE power supply is prone to the phenomenon of horn speakers operating at low power continuously (that is, the loudspeaker continuously operating below its rated power), which makes the volume emitted by the horn speaker to the outside world small and the sound quality poor (i.e., poor audio broadcasting effect).

[0024] It should be noted that the aforementioned related technologies are only used to assist in understanding the technical solutions of this application and do not mean that they belong to the publicly disclosed prior art.

[0025] In view of this, the present utility model application provides an audio broadcasting device and a network broadcasting system. The audio broadcasting device automatically switches the output power according to the different power supply methods through a power switching module. Specifically, when the audio broadcasting device is powered by DC power, the output power is controlled to be the second power, while when only POE power is supplied, the output power is controlled to be the first power. It can automatically switch the output power according to the different power supply methods, so that the speaker module of the audio broadcasting device can broadcast at the normal operating power when powered by DC power, which is beneficial to improving the audio broadcasting effect.

[0026] Reference Figure 1 Specifically, an audio broadcasting device according to an embodiment of this application includes: a main control module, a power amplifier module, a power switching module, and a speaker module; The output terminal of the main control module is connected to the first input terminal of the power switching module, the output terminal of the power switching module is connected to the input terminal of the power amplifier module, and the output terminal of the power amplifier module is connected to the speaker module. The second input terminal of the power switching module is connected to an external POE power supply and / or DC power supply. When the second input terminal of the power switching module is independently powered by the POE power supply, the output power of the power switching module is the first power; when the second input terminal of the power switching module is independently powered by the DC power supply, the output power of the power switching module is the second power; when the second input terminal of the power switching module is powered by a combination of the DC power supply and the POE power supply, the output power of the power switching module is the second power, and the second power is greater than the first power.

[0027] In some embodiments, the main control module includes a network interface and a control chip; The network interface is connected to the input terminal of the control chip, and the output terminal of the control chip is connected to the power switching module.

[0028] Reference Figure 2 In some embodiments, the power switching module includes a drive amplification unit 201, a power supply indication unit 204, an operational amplification unit 203, and a switching unit 202; The first input terminal of the drive amplification unit 201 is connected to the output terminal of the main control module, and the first output terminal of the drive amplification unit 201 is connected to the first input terminal of the switching unit 202. The output of the switching unit 202 is connected to the driving amplification unit 201 via the operational amplification unit 203, and the second output of the driving amplification unit 201 is connected to the input of the power amplifier module. The input terminal of the power supply indicator unit 204 is connected to a POE power supply and / or a DC power supply, the first output terminal of the power supply indicator unit 204 is connected to the second input terminal of the switching unit 202, and the second output terminal of the power supply indicator unit 204 is connected to the third input terminal of the switching unit 202.

[0029] Reference Figure 3 In some embodiments, the power supply indicator unit 204 includes a first resistor R1, a second resistor R3, a third resistor R4, a fourth resistor R6, a first diode D1, a second diode D2, a transistor Q1, and a first capacitor C4. One end of the first resistor R1 is connected to the DC power supply, and the other end of the first resistor R1 is connected to the second input terminal of the switching unit 202. One end of the second resistor R3 is connected to the POE power supply, and the other end of the second resistor R3 is connected to the third input terminal of the switching unit 202; The positive terminal of the first diode D1 is connected to one end of the first resistor R1, the negative terminal of the first diode D1 is connected to the negative terminal of the second diode D2, and the positive terminal of the second diode D2 is connected to one end of the second resistor R3. The collector of transistor Q1 is connected to the other end of the second resistor R3, the base of transistor Q1 is connected to one end of the fourth resistor R6, and the other end of the fourth resistor R6 is connected to the other end of the first resistor R1. The emitter of the transistor Q1 is connected to one end of the first capacitor C4, one end of the third resistor R4 is connected to one end of the first capacitor C4, the other end of the third resistor R4 is connected to the other end of the first capacitor C4, one end of the fourth resistor R6 is connected to the other end of the first capacitor C4, and one end of the first capacitor C4 is grounded.

[0030] Reference Figure 4 In some embodiments, the operational amplifier unit 203 includes a second capacitor C9, a third capacitor C14, a fourth capacitor C10, a fifth resistor R11, a sixth resistor R12, and a seventh resistor R13. One end of the second capacitor C9 is connected to the first output terminal of the switching unit 202, and the other end of the second capacitor C9 is connected to one end of the fifth resistor R11. The other end of the fifth resistor R11 is connected to the second input terminal of the driving amplifier unit 201. One end of the third capacitor C14 is connected to the second output terminal of the switching unit 202, and one end of the third capacitor C14 is connected to one end of the sixth resistor R12. The other end of the sixth resistor R12 is connected to the second output terminal of the driving amplifier unit 201 via the seventh resistor R13. The second end of the drive amplifier unit 201 is connected to the other end of the sixth resistor R12 via the fourth capacitor C10, and the other end of the sixth resistor R12 is connected to the other end of the fifth resistor R11.

[0031] Reference Figure 5 In some embodiments, the switching unit 202 includes a switching chip, and the output of the switching chip is connected to the driving amplification unit 201 via the operational amplification unit 203.

[0032] Reference Figure 6 In some embodiments, the drive amplification unit 201 includes a first power amplifier chip, which is connected to the input terminal of the power amplifier module.

[0033] Reference Figure 7 In some embodiments, the power amplifier module includes a second power amplifier chip connected to the speaker module.

[0034] This application provides an audio broadcasting system, including a network service host and the aforementioned audio broadcasting device, wherein the network service host is communicatively connected to the audio broadcasting device.

[0035] The power amplifier and audio broadcasting system provided in this application will be described in detail below with a specific embodiment: To address the aforementioned deficiencies in the prior art, this application provides an audio broadcasting device. The audio broadcasting device comprises as follows: Figure 1 As shown, it includes a main control module, a power amplifier module, a power switching module, and a speaker module; while the network broadcasting system includes a network service host that communicates with the audio broadcasting device.

[0036] The working principle of this audio broadcasting device and internet broadcasting system is as follows: The control chip in the main control module (such as an ARM Cortex-A7 core chip) receives network audio digital signals sent by the network service host through the network interface. After being decoded into network audio analog signals by the control chip, these signals are transmitted to the speaker module via the power switching module and the power module, enabling the speaker module to broadcast network audio. When transmitting the network audio analog signals, the power switching module automatically switches the output power according to the power supply control signal indicated by the power supply indicator unit, ensuring that the output power is the second power when DC power is available, and the output power is the first power when only PoE power is available. This allows the speaker module of the audio broadcasting device to broadcast at its normal operating power when powered by DC power.

[0037] This application embodiment uses the network audio analog signal output by the control chip as the AUX_IN signal and sets the load resistance of the speaker module to 4 ohms as an example. A preferred embodiment of the audio broadcasting device is as follows: Reference Figures 2 to 6 The network audio analog signal AUX_IN output by the control chip is input to the first power amplifier chip U1 (specifically the tenth pin of the SGM8904 chip) via capacitor C5 and resistor R5 for pre-amplification. The amplified signal is output from the ninth pin of the first power amplifier chip U1 and split into two signals, namely DC_IN signal and POE_IN signal.

[0038] The POE_IN signal undergoes noise cancellation via switching chip U2 (specifically input to the third pin of the SGM4804 chip) and is output from the eleventh pin of the switching chip. Then, after being amplified by a fixed factor through the third capacitor C14, the sixth resistor R12, and the seventh resistor R13, it is input to the first pin of the first power amplifier chip U1. This POE_IN signal, after being amplified by the first and second power amplifier chips, is then input to the speaker module for its operation. Specifically, with the voltage of the POE_IN signal at the other end of the fifth resistor R11 set to approximately 0.45V, and the total amplification factor of the first and second power amplifier chips set to 20, the voltage across the speaker module is 9V. This voltage is achieved when a 4-ohm load is connected (without...). Figures 2 to 7 As shown), according to Ohm's law, the output power of the speaker module can be determined to be 20W (rounded to the nearest integer, which is the first power).

[0039] The DC_IN signal undergoes noise cancellation via switching chip U2 (specifically input to the first pin of the SGM4804 chip) and is output from the twelfth pin of the switching chip. Then, after being amplified by a fixed factor through the second capacitor C9, the fifth resistor R11, and the seventh resistor R13, it is input to the first pin of the first power amplifier chip U1. This DC_IN signal, after being amplified by both the first and second power amplifier chips, is then input to the speaker module for normal operation. Specifically, the voltage of the DC_IN signal at the other end of the fifth resistor R11 is set to approximately 0.75V, and the total amplification factor of the first and second power amplifier chips is set to 20 times. Therefore, the voltage across the speaker module is 15V when connected to a 4-ohm load (without...). Figures 2 to 7 As shown), its output power is approximately 56W (rounded to the nearest integer, which is the second power).

[0040] When powered only by PoE power supply POEV_IN, pin 15 of switching chip U2 is high, while pin 14 is low. The internal circuitry from pin 3 to pin 11 of switching chip U2 is active, while the internal circuitry from pin 1 to pin 12 is deactivated. Therefore, when powered only by PoE power supply POEV_IN, switching chip U2 outputs the POE_IN signal from pin 11, and the DC_IN signal is not output from pin 12.

[0041] When powered only by DC power supply DCV_IN, pin 14 of switching chip U2 is high, while pin 15 is low. The internal circuitry from pin 3 to pin 11 of switching chip U2 is disconnected, while the internal circuitry from pin 1 to pin 12 is connected. Therefore, when powered only by DC power supply DCV_IN, switching chip U2 outputs the DC_IN signal from pin 12, and the POE_IN signal is not output from pin 11.

[0042] When both DC power supply DCV_IN and POE power supply POEV_IN are used simultaneously, pin 14 of switching chip U2 is high, and due to the presence of resistor R6, transistor Q1 is turned on, causing pin 15 of switching chip U2 to be low. Therefore, the specific situation when using both DC power supply DCV_IN and POE power supply POEV_IN is similar to the situation when using only DC power supply DCV_IN, and can be easily deduced by analogy.

[0043] Participate in the group Figure 7The second power amplifier chip can be a TPA3116 chip. The AMP_IN signal output from the second pin of the first power amplifier chip U1 is input to the TPA3116 chip for power amplification through capacitor C23 and resistor R16, and the amplified AMP_IN signal is output to the speaker module (such as a horn speaker) through the P2 interface so that the speaker module can emit broadcast sound.

[0044] It is worth mentioning that the audio broadcasting device does not involve any software improvements, and the software aspects can be easily derived from existing technology.

[0045] In the description of this specification, references to terms such as "one embodiment," "another embodiment," or "some embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An audio broadcasting device, characterized in that, It includes a main control module, a power amplifier module, a power switching module, and a speaker module; The output terminal of the main control module is connected to the first input terminal of the power switching module, the output terminal of the power switching module is connected to the input terminal of the power amplifier module, and the output terminal of the power amplifier module is connected to the speaker module. The second input terminal of the power switching module is connected to an external POE power supply and / or DC power supply. When the second input terminal of the power switching module is independently powered by the POE power supply, the output power of the power switching module is the first power; when the second input terminal of the power switching module is independently powered by the DC power supply, the output power of the power switching module is the second power; when the second input terminal of the power switching module is powered by a combination of the DC power supply and the POE power supply, the output power of the power switching module is the second power, and the second power is greater than the first power.

2. The audio broadcasting device according to claim 1, characterized in that, The main control module includes a network interface and a control chip; The network interface is connected to the input terminal of the control chip, and the output terminal of the control chip is connected to the power switching module.

3. The audio broadcasting device according to claim 1, characterized in that, The power switching module includes a drive amplification unit, a power supply indication unit, an operational amplification unit, and a switching unit; The first input terminal of the drive amplification unit is connected to the output terminal of the main control module, and the first output terminal of the drive amplification unit is connected to the first input terminal of the switching unit. The output of the switching unit is connected to the driving amplification unit via the operational amplification unit, and the second output of the driving amplification unit is connected to the input of the power amplifier module. The input terminal of the power supply indicator unit is connected to a PoE power supply and / or a DC power supply, the first output terminal of the power supply indicator unit is connected to the second input terminal of the switching unit, and the second output terminal of the power supply indicator unit is connected to the third input terminal of the switching unit.

4. The audio broadcasting device according to claim 3, characterized in that, The power supply indicator unit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a first diode, a second diode, a transistor, and a first capacitor; One end of the first resistor is connected to the DC power supply, and the other end of the first resistor is connected to the second input terminal of the switching unit; One end of the second resistor is connected to the POE power supply, and the other end of the second resistor is connected to the third input terminal of the switching unit; The anode of the first diode is connected to one end of the first resistor, the cathode of the first diode is connected to the cathode of the second diode, and the anode of the second diode is connected to one end of the second resistor; The collector of the transistor is connected to the other end of the second resistor, the base of the transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is connected to the other end of the first resistor. The emitter of the transistor is connected to one end of the first capacitor, one end of the third resistor is connected to one end of the first capacitor, the other end of the third resistor is connected to the other end of the first capacitor, one end of the fourth resistor is connected to the other end of the first capacitor, and one end of the first capacitor is grounded.

5. The audio broadcasting device according to claim 3, characterized in that, The operational amplifier unit includes a second capacitor, a third capacitor, a fourth capacitor, a fifth resistor, a sixth resistor, and a seventh resistor; One end of the second capacitor is connected to the first output terminal of the switching unit, and the other end of the second capacitor is connected to one end of the fifth resistor, and the other end of the fifth resistor is connected to the second input terminal of the drive amplifier unit. One end of the third capacitor is connected to the second output terminal of the switching unit, one end of the third capacitor is connected to one end of the sixth resistor, and the other end of the sixth resistor is connected to the second output terminal of the driving amplifier unit via the seventh resistor; The second end of the drive amplifier unit is connected to the other end of the sixth resistor via the fourth capacitor, and the other end of the sixth resistor is connected to the other end of the fifth resistor.

6. The audio broadcasting device according to claim 3, characterized in that, The switching unit includes a switching chip, and the output of the switching chip is connected to the driving amplification unit via the operational amplification unit.

7. The audio broadcasting device according to claim 3, characterized in that, The drive amplification unit includes a first power amplifier chip, which is connected to the input terminal of the power amplifier module.

8. The audio broadcasting device according to claim 1, characterized in that, The power amplifier module includes a second power amplifier chip, which is connected to the speaker module.

9. The audio broadcasting device according to claim 1, characterized in that, The speaker module is a horn speaker.

10. A network broadcasting system, characterized in that, It includes a network service host and an audio broadcasting device as described in any one of claims 1-9, wherein the network service host is communicatively connected to the audio broadcasting device.

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