Audio processing system and method based on input channel expansion

Abstract

The present invention provides an audio processing system and method based on input channel expansion. The system includes a network switch and a central audio processor, a hall audio processor and a control terminal connected thereto; the central audio processor is used to process the input audio signal; the hall audio processor is used to process the digital audio signal output by the central audio processor and output an analog audio signal to a playback device; the central audio processors are connected into a tree structure through the network switch, and some digital output channels of the central audio processor, a child node of the tree structure, are connected one-to-one with the digital input channels of the central audio processor, a parent node, and some digital output channels of the central audio processor, a root node, are transmitted to the corresponding hall audio processor via the network switch. By connecting the audio processors into a tree structure, the present invention can increase the number of audio processor input channels and solve the problem of limited processing capacity of the audio processor.

Description

Technical Field

[0001] The present invention belongs to the technical field of audio processing, and in particular relates to an audio processing system and method based on input channel expansion. Background Art

[0002] Audio signal network transmission technology is becoming increasingly common in modern audio systems. It supports high sampling rates and high bit depths, ensuring high-quality audio signal transmission. Adhering to the industry standard AES67 improves audio system scalability. AES67 is a standard developed by the Audio Engineering Society to ensure interoperability between different Audio over IP (AoIP) systems. This standard provides a framework for seamless communication between devices from different manufacturers over IP networks. It defines how to transparently transmit professional audio signals over IP networks. It is compatible with multiple network audio protocols, such as Dante, Ravenna, Q-Lan, and Livestream. It supports precise time synchronization, ensuring audio synchronization between multiple devices. It provides low-latency, high-quality audio transmission. Dante (Digital Audio Network over Ethernet) is an Ethernet-based digital audio transmission technology developed by Audinate. It allows users to efficiently transmit high-quality audio signals over a standard Ethernet infrastructure. Featuring high quality, low latency, and high reliability, it is a mainstream audio signal transmission protocol for audio processing equipment, holding the highest market share and being a standard feature in most audio processors. Due to US chip restrictions, the maximum audio signal processing capability of domestic Dante processing chips is mostly 64*64, limiting the signal processing capacity of a single audio processing device. This poses a significant limitation for large-scale audio processing systems that manage multiple halls simultaneously, making it impossible for the audio system to simultaneously dispatch all audio signals.

[0003] The existing method for mixing and transmitting audio signals involves connecting multiple halls' audio processors to a central audio processor via a network, forming a star-shaped structure (the central audio processing device has the largest signal processing capacity). Each hall's audio signal pickup and amplification are handled by its own audio processing device, which then mixes the processed audio signals into one or more Dante audio signals for output to the central audio processing device. The central audio processing device also receives one or more Dante audio signals from the central audio processing device, which then controls the forwarding of audio signals across halls. This existing mixing method presents challenges such as increased control complexity, inability to accurately control, and compromised sound quality. Summary of the Invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides an audio processing system and method based on input channel expansion.

[0005] In order to achieve the above objectives, the present invention adopts the following technical solutions.

[0006] In the first aspect, the present invention provides an audio processing system based on input channel expansion, including a network switch and a central audio processor, a hall audio processor and a control terminal connected thereto; the central audio processor is used to process the input audio signal, and the output digital audio signal is sent to the hall audio processor via the network switch; the hall audio processor is used to process the digital audio signal output by the central audio processor and output an analog audio signal to a playback device; the central audio processors are connected into a tree structure through the network switch, and some digital output channels of the central audio processor, a child node of the tree structure, are connected one-to-one with the digital input channels of the central audio processor, a parent node of the tree structure, and there is only one central audio processor at the root node, and some of its digital output channels are transmitted to the corresponding hall audio processor via the network switch.

[0007] Furthermore, among all the central audio processors in the tree structure, the root node central audio processor has the largest number of digital input channels.

[0008] Furthermore, the central audio processor is provided with an analog input channel, an analog output channel, a digital input channel, and a digital output channel.

[0009] Furthermore, the number of input channels after tree structure expansion is:

[0010] S=S1+S2-S3

[0011] Where S is the number of input channels after expansion, S1 and S2 are the number of analog input channels and digital input channels of all central audio processors, respectively, and S3 is the number of digital output channels connected to the central audio processor of all non-root nodes and their parent nodes.

[0012] Furthermore, the Y-channel digital output channel of the child node central audio processor of the tree structure is connected one-to-one with the Y-channel digital input channel of its parent node central audio processor, and the Y-channel digital output channel of the root node central audio processor of the tree structure is connected to the network switch; Y is the maximum value of the signal channel that the central audio processor of the tree structure can broadcast, and Y is less than the minimum value of the number of analog input channels, digital input channels and digital output channels of each central audio processor.

[0013] Furthermore, the operator can send data transmission instructions through the manual interaction interface of the control terminal to transmit the audio signals of one or more specified input channels of the central audio processor to the specified digital output channels of the root node central audio processor; after the control terminal parses the instructions, it realizes the data transmission by outputting control instructions.

[0014] Further, when the analog audio signal to be transmitted is the analog audio signal input to the central audio processor, the analog audio signal is first converted into a digital audio signal and then output by the digital output channel.

[0015] Further, the central audio processor includes processor A and processor B. Processor A is the root node central audio processor; the number of analog input channels of processor A is A1, the number of digital input channels is A2, the number of analog output channels is A11, and the number of digital output channels is A12; the number of analog input channels of audio processor B is B1, the number of digital input channels is B2, the number of analog output channels is B11, and the number of digital output channels is B12.

[0016] Further, the transmission method for transmitting the input audio signal with channel number x to the digital output channel with channel number y of processor A includes:

[0017] If x ≤ A1, after converting the x-th analog input signal of processor A into a digital signal, it is output by the y-th digital output channel of processor A;

[0018] If A1 < x ≤ A1 + B1, after converting the (x - A1)-th analog input signal of processor B into a digital signal, it is output by the digital output channel of processor B to the digital input channel of processor A and then output by the y-th digital output channel of processor A; <0**********39>

[0019] If A1 + B1 < x ≤ A1 + B1 + B2, the (x - A1 - B1)-th digital input signal of processor B is output by the digital output channel of processor B to the digital input channel of processor A and then output by the y-th digital output channel of processor A;

[0020] If A1 + B1 + B2 < x ≤ A1 + B1 + B2 + A2 - Y, the (Y + x - A1 - B1 - B2)-th digital input signal of processor A is output by the y-th digital output channel of processor A;

[0021] Among them, 1 ≤ y ≤ Y.

[0022] In a second aspect, the present invention provides a method for expanding the input channels by applying the system, including the following steps:

[0023] Determine the root node central audio processor and each level of child node central audio processors of the tree structure;

[0024] One-to-one connect some of the digital output channels of the child node central audio processor to the digital input channels of its parent node central audio processor;

[0025] Connect some digital output channels of the root node central audio processor to the network switch.

[0026] Compared with the prior art, the present invention has the following beneficial effects.

[0027] The present invention comprises a network switch and a central audio processor connected thereto, a hall audio processor, and a control terminal. The central audio processors are connected to form a tree structure via the network switch. Part of the digital output channels of the central audio processors, which are child nodes of the tree structure, are connected one-to-one with the digital input channels of the central audio processors, which are parent nodes. There is only one central audio processor at the root node, and part of its digital output channels are transmitted to the corresponding hall audio processors via the network switch, thereby achieving expansion of the audio processor input channels. By connecting the central audio processors into a tree structure via the network switch, the present invention expands the number of audio signal input channels, solves the problem of limited processing power of the audio processors, simplifies cumbersome control steps, and improves the ability to accurately control audio signals and the broadcast effect. The system can be applied to various large and complex professional audio systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The present invention provides a block diagram of an audio processing system based on input channel expansion according to an embodiment of the present invention.

[0029] In the figure, 1-network switch, 2-central audio processor, 3-hall audio processor, 4-control terminal.

[0030] Figure 2 Schematic diagram of a tree structure connected by central audio processors.

[0031] Figure 3 The present invention is a flowchart of a method for expanding input channel capacity by applying the system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] To make the objectives, technical solutions, and advantages of the present invention more clear and understandable, the present invention is further described below with reference to the accompanying drawings and specific embodiments. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] Figure 1This is a schematic diagram of the composition of an audio processing system based on input channel expansion according to an embodiment of the present invention, comprising a network switch 1 and a central audio processor 2, a hall audio processor 3 and a control terminal 4 connected thereto; the central audio processor 2 is used to process the input audio signal, and the output digital audio signal is sent to the hall audio processor 3 via the network switch 1; the hall audio processor 3 is used to process the digital audio signal output by the central audio processor 2, and output an analog audio signal to the playback device; the central audio processor 2 is connected into a tree structure through the network switch 1, and some digital output channels of the central audio processor 2, a child node of the tree structure, are connected one-to-one with the digital input channels of the central audio processor 2, its parent node; there is only one central audio processor 2 at the root node, and some of its digital output channels are transmitted to the corresponding hall audio processor 3 via the network switch 1.

[0034] In this embodiment, the system mainly consists of a network switch 1 and a central audio processor 2, a hall audio processor 3 and a control terminal 4 connected thereto. The connection relationship between each part is as follows: Figure 1 The following describes the functions of each part.

[0035] The central audio processor 2 is the main functional device of the system, which is mainly used to process the input audio signal, such as audio amplification, noise removal, sound quality optimization, analog-to-digital conversion, etc. The output digital audio signal is sent to the hall audio processor 3 via the network switch 1.

[0036] The hall audio processor 3 shares the same hardware structure as the central audio processor 2, but their functions differ in this embodiment. The hall audio processor 3 primarily serves as the physical cable connection for the output signals of all audio source devices, including sound pickups, musical instruments, and multimedia. It also serves as the physical cable connection for all amplifiers, speakers, monitoring, and recording equipment. It receives the digital audio signals output by the central audio processor 2, converts the input analog audio signals into digital audio signals, and transmits them to the digital audio input channel of the central audio processor 2 via the network switch 1.

[0037] The network switch 1 is the connection link between the central audio processor 2, the hall audio processor 3 and the control terminal 4. The central audio processor 2 and the hall audio processor 3 are connected to the network switch 1 via a data cable for transmitting digital audio signals; the control terminal 4 is connected to the network switch 1 via a network cable to achieve control of the central audio processor 2 and the hall audio processor 3. In this embodiment, the connection between different central audio processors 2 is also achieved through the network switch 1. For example, in order to achieve the expansion of the input channel of the central audio processor 2, this embodiment connects the central audio processors 2 into a tree structure through the network switch 1, such as Figure 2 shown.

[0038] Control terminal 4 is the control center of the system, primarily responsible for coordinating the operations of central audio processor 2 and hall audio processor 3 by outputting control commands. Control terminal 4 primarily controls the gain and routing of the audio processor inputs, outputs, and routing, as well as controls for reverse, insertion, phantom power, compression, limiting, equalization, high-pass, low-pass, and delay.

[0039] This embodiment expands the number of input channels of the central audio processor 2 by connecting the central audio processor 2 into a tree structure. Figure 2 As shown, some of the digital output channels of the child node Central Audio Processor 2 in the tree structure are connected one-to-one with the digital input channels of its parent node Central Audio Processor 2. There is only one Central Audio Processor 2 at the root node. Clearly, the greater the number of Central Audio Processors 2, the more significant the expansion effect. However, the expansion design also needs to consider the increased latency caused by the increase in the number of levels.

[0040] As an optional embodiment, among all the central audio processors 2 in the tree structure, the root node central audio processor 2 has the largest number of digital input channels.

[0041] This embodiment provides a selection scheme for the root node central audio processor 2. This embodiment selects the one with the largest number of digital input channels from all central audio processors 2 as the root node. The purpose of this process is to reduce data transmission delay. The principle is that the fewer the levels of the tree structure, the smaller the delay. Selecting the root node in this way can maximize the number of first-level child nodes under the root node, which is conducive to reducing the number of levels of child nodes, thereby reducing delay. Similarly, the central audio processor 2 with the largest number of digital input channels should be selected as the child node at the front of the hierarchy as much as possible.

[0042] As an optional embodiment, the central audio processor 2 is provided with an analog input channel, an analog output channel, a digital input channel, and a digital output channel.

[0043] This embodiment defines the audio input / output channels of the central audio processor 2. While the previous embodiment only mentioned the digital input channels of the central audio processor 2, typical audio processors typically have two types of audio signal input channels: analog audio signal input / output channels (abbreviated as analog input / output channels) and digital audio signal input / output channels (abbreviated as digital input / output channels). These two types of input / output channels are designed to accommodate different types of signal sources and playback devices.

[0044] As an optional embodiment, the number of input channels after expansion using a tree structure is:

[0045] S=S1+S2-S3

[0046] Where S is the number of input channels after expansion, S1 and S2 are the number of analog input channels and digital input channels of all central audio processors 2, respectively, and S3 is the number of digital output channels connected to the central audio processor 2 of all non-root nodes and their parent nodes.

[0047] This embodiment provides a technical solution for calculating the number of input channels after expansion. Figure 2 , part of the digital output channels of each child node central audio processor 2 occupies the same number of digital input channels of its parent node central audio processor 2. Therefore, as long as the sum of the number of analog and digital input channels of all central audio processors 2 (S1+S2) is subtracted from the number of digital output channels S3 connected to all central audio processors 2 except the root node and their parent node central audio processor 2, the number of input channels S after expansion can be obtained.

[0048] As an optional embodiment, the Y-channel digital output channel of the child node central audio processor 2 of the tree structure is connected one-to-one with the Y-channel digital input channel of its parent node central audio processor 2, and the Y-channel digital output channel of the root node central audio processor 2 of the tree structure is connected to the network switch 1; Y is the maximum value of the signal channel that the central audio processor 2 of the tree structure can broadcast, and Y is less than the minimum value of the number of analog input channels, digital input channels and digital output channels of each central audio processor 2.

[0049] This embodiment provides a specific connection method for a tree structure. The root node central audio processor 2 of this embodiment has Y digital output channels connected to the network switch 1, and the other child node central audio processors 2 all have Y digital output channels that are one-to-one connected to the Y digital input channels of their parent node central audio processor 2. Y is the maximum value of the signal channels that the central audio processor 2 of the tree structure can broadcast. In order to avoid the extreme situation where the upper limit of the number of channels is exceeded because all digital audio signals come from the same central audio processor 2, the value of Y must not exceed the minimum value of the number of analog input channels, digital input channels and digital output channels of each central audio processor 2.

[0050] As an optional embodiment, the operator can send a data transmission instruction through the manual interaction interface of the control terminal 4 to transmit the audio signal of one or more specified input channels of the central audio processor 2 to the specified digital output channel of the root node central audio processor 2; after the control terminal 4 parses the instruction, it realizes the data transmission by outputting a control instruction.

[0051] This embodiment provides a technical solution for realizing audio data transmission. For the convenience of operation, a manual interaction interface implemented by software is designed at the control terminal 4, through which the operator can conveniently perform various operations. For example, a data transmission instruction is sent to transmit the audio signal (including analog audio signal and digital audio signal) of one or more specified input channels of the central audio processor 2 to the specified digital output channel of the root node central audio processor 2, and then to the hall audio processor 3 through the network switch 1. The specific implementation process is that the control terminal 4 receives and parses the instructions issued by the operator, and then realizes the data transmission by outputting control instructions.

[0052] As an optional embodiment, when an analog audio signal input to the central audio processor 2 needs to be transmitted, the analog audio signal is first converted into a digital audio signal and then output through a digital output channel.

[0053] This embodiment provides a technical solution for transmitting analog audio signals. Since the child nodes of the tree structure of this embodiment are connected to their parent nodes only through digital channels, that is, analog audio signals are not directly transmitted between the central audio processors 2, when analog audio signals need to be transmitted, they need to be converted into digital audio signals before transmission.

[0054] As an optional embodiment, the central audio processor 2 includes processor A and processor B, processor A is the root node central audio processor 2; the number of analog input channels of processor A is A1, the number of digital input channels is A2, the number of analog output channels is A11, and the number of digital output channels is A12; the number of analog input channels of audio processor B is B1, the number of digital input channels is B2, the number of analog output channels is B11, and the number of digital output channels is B12.

[0055] This embodiment provides a simplest tree structure consisting of only two central audio processors 2. The two central audio processors 2 are processor A and processor B, with processor A being the root node central audio processor 2, i.e. A and B are connected in series, with B first and A second. The number of analog input channels, digital input channels, analog output channels and digital output channels of processor A are A1, A2, A11 and A12 respectively; the number of analog input channels, digital input channels, analog output channels and digital output channels of processor B are B1, B2, B11 and B12 respectively. The Y-channel digital output channel of processor B is connected to the Y-channel digital input channel of processor A, and the Y-channel digital output channel of processor A is connected to the network switch 1. Among them, Y <min{A1,A2,A12,B1,B2,B12}。

[0056] As an optional embodiment, the transmission method for transmitting an input audio signal with channel number x to the digital output channel with channel number y of processor A includes:

[0057] If x ≤ A1, after converting the x-th analog input signal of processor A into a digital signal, it is output through the y-th digital output channel of processor A;

[0058] If A1 < x ≤ A1 + B1, after converting the (x - A1)-th analog input signal of processor B into a digital signal, it is output through the digital output channel of processor B to the digital input channel of processor A, and then output through the y-th digital output channel of processor A;

[0059] If A1 + B1 < x ≤ A1 + B1 + B2, the (x - A1 - B1)-th digital input signal of processor B is output through the digital output channel of processor B to the digital input channel of processor A, and then output through the y-th digital output channel of processor A;

[0060] If A1 + B1 + B2 < x ≤ A1 + B1 + B2 + A2 - Y, the (Y + x - A1 - B1 - B2)-th digital input signal of processor A is output through the y-th digital output channel of processor A;

[0061] Where, 1 ≤ y ≤ Y.

[0062] This embodiment provides a technical solution for data transmission with the simplest tree structure. In this embodiment, the analog and digital input channels of processors A and B are uniformly numbered, and the channel numbers are all represented by x, where the value range of x is 1 ≤ x ≤ A1 + A2 + B1 + B2 - Y. This embodiment provides a solution for outputting the x-th audio signal to the y-th digital output channel of processor A, where 1 ≤ y ≤ Y.

[0063] The numbers of the A1 analog input channels of processor A are 1 to A1. When x ≤ A1, the x-th analog input signal of processor A needs to be transmitted. Since a digital signal needs to be output finally, first processor A converts the analog input signal into a digital signal and then outputs it through the y-th digital output channel of processor A.

[0064] The numbers of the B1 analog input channels of processor B are A1 + 1 to A1 + B1. When A1 < x ≤ A1 + B1, the (x - A1)-th analog input signal of processor B needs to be transmitted. Similarly, first processor B converts the analog input signal into a digital signal and then outputs it through the y-th digital output channel of processor A.

[0065] The numbers of the digital input channels of the B2 channels of Processor B are from A1 + B1 + 1 to A1 + B1 + B2. When A1 + B1 < x ≤ A1 + B1 + B2, the digital input signal of the (x - A1 - B1)-th channel of Processor B to be transmitted is output from the digital output channel of Processor B to the digital input channel of Processor A and then output from the y-th digital output channel of Processor A.

[0066] Processor A has a total of A2 digital input channels, among which the 0 - Y channels are occupied by the digital output channels of Processor B, and there are A2 - Y available channels. When A1 + B1 + B2 < x ≤ A1 + B1 + B2 + A2 - Y, the signal of the (Y + x - A1 - B1 - B2)-th digital input channel of Processor A to be transmitted is output from the y-th digital output channel of Processor A.

[0067] Figure 3 The following is a flowchart of a method for expanding the input channels by applying the system in an embodiment of the present invention, including the following steps:

[0068] Step 101: Determine the root node central audio processor 2 and the central audio processors 2 of each level of child nodes of the tree structure;

[0069] Step 102: Connect part of the digital output channels of the central audio processor 2 of the child node to the digital input channels of its parent node central audio processor 2 one-to-one;

[0070] Step 103: Connect part of the digital output channels of the root node central audio processor 2 to the network switch 1.

[0071] The method of this embodiment, compared with Figure 1 the technical solution of the system embodiment shown, has a similar implementation principle and technical effect, which will not be elaborated here.

[0072] As mentioned above, the above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any change or replacement that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. An audio processing system based on input channel expansion, characterized in that: It includes a network switch and a central audio processor, a hall audio processor and a control terminal connected thereto; the central audio processor is used to process the input audio signal and send the output digital audio signal to the hall audio processor via the network switch; the hall audio processor is used to process the digital audio signal output by the central audio processor and output analog audio signal to the playback device; The central audio processors are connected into a tree structure through a network switch. Some digital output channels of the central audio processors at the child nodes of the tree structure are connected one-to-one with the digital input channels of the central audio processors at their parent nodes. There is only one central audio processor at the root node, and some of its digital output channels are transmitted to the corresponding hall audio processors through the network switch.

2. The audio processing system based on input channel expansion according to claim 1, characterized in that: Among all the central audio processors in the tree structure, the root node central audio processor has the largest number of digital input channels.

3. The audio processing system based on input channel expansion according to claim 1, characterized in that: The central audio processor is provided with an analog input channel, an analog output channel, a digital input channel, and a digital output channel.

4. The audio processing system based on input channel expansion according to claim 3, characterized in that: The number of input channels after tree structure expansion is: S=S1+S2-S3 Where S is the number of input channels after expansion, S1 and S2 are the number of analog input channels and digital input channels of all central audio processors, respectively, and S3 is the number of digital output channels connected to the central audio processor of all non-root nodes and their parent nodes.

5. The audio processing system based on input channel expansion according to claim 3, characterized in that: The Y-channel digital output channel of the child node central audio processor of the tree structure is connected one-to-one with the Y-channel digital input channel of its parent node central audio processor, and the Y-channel digital output channel of the root node central audio processor of the tree structure is connected to the network switch; Y is the maximum value of the signal channel that the central audio processor of the tree structure can broadcast, and Y is less than the minimum value of the number of analog input channels, digital input channels and digital output channels of each central audio processor.

6. The audio processing system based on input channel expansion according to claim 3, characterized in that: The operator can send data transmission instructions through the manual interaction interface of the control terminal to transmit the audio signals of one or more specified input channels of the central audio processor to the specified digital output channels of the root node central audio processor; after the control terminal parses the instructions, it realizes the data transmission by outputting control instructions.

7. The audio processing system based on input channel expansion according to claim 3, characterized in that: When the analog audio signal input to the central audio processor needs to be transmitted, the analog audio signal is first converted into a digital audio signal and then output through the digital output channel.

8. The audio processing system based on input channel expansion according to claim 3, characterized in that: The central audio processor includes processor A and processor B, processor A is the root node central audio processor; the number of analog input channels of processor A is A1, the number of digital input channels is A2, the number of analog output channels is A11, and the number of digital output channels is A12; the number of analog input channels of audio processor B is B1, the number of digital input channels is B2, the number of analog output channels is B11, and the number of digital output channels is B12.

9. The audio processing system based on input channel expansion according to claim 8, characterized in that: The method for transmitting an input audio signal with a channel number of x to a digital output channel with a channel number of y of processor A includes: If x ≤ A1, after converting the x-th analog input signal of processor A into a digital signal, it is output through the y-th digital output channel of processor A; If A1 < x ≤ A1 + B1, after converting the (x - A1)-th analog input signal of processor B into a digital signal, it is output through the digital output channel of processor B to the digital input channel of processor A, and then output through the y-th digital output channel of processor A; If A1 + B1 < x ≤ A1 + B1 + B2, the (x - A1 - B1)-th digital input signal of processor B is output through the digital output channel of processor B to the digital input channel of processor A, and then output through the y-th digital output channel of processor A; If A1 + B1 + B2 < x ≤ A1 + B1 + B2 + A2 - Y, the (Y + x - A1 - B1 - B2)-th digital input signal of processor A is output through the y-th digital output channel of processor A; where 1 ≤ y ≤ Y.

10. A method for expanding input channels using the system of claim 1, characterized in that: It includes the following steps: Determine the root node central audio processor and the central audio processors at all levels of child nodes of the tree structure; Connect the partial digital output channels of the child node central audio processors to the digital input channels of their parent node central audio processors one by one; Connect the partial digital output channels of the root node central audio processor to the network switch.

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