Remote Mute Server (remote mute / master mute)
Remote Mute Server provides remote mute, master mute, and server mute for MAXX amplifiers: a UDP-based GPI-style mute that emulates a classical dead-man’s switch. In all MAXX Series amplifiers, the REMOTE MUTE feature mutes the device via UDP messages when the server requests mute or stops answering.
Overview
In a typical application, a single GPI controls multiple devices, like in an acoustic research lab, where the door contact to the acoustic chamber disables the whole system to prevent hearing damage. On the other hand, it can be used as a simple GLOBAL MUTE for the system, where the user purposely wants to activate it by hand.
All amplifiers which has the REMOTE MUTE enabled, act as an client and periodically sends requests to the configured server to ask for its current MUTE GPI state.
The Device will either mute itself when:
- The server actively sends the state to be MUTE
- Or the device will not receive a response message from the server within a given time period (~400ms), so it is assumed to be ‘offline’
Protocol
For sake of simplicity and robustness, the protocol is stateless and consists of a single header with integer IDs and value. Which can also be implemented in different programming languages to use without a hardware server.
The server has to listen to UDP port 9460 for incoming REQ messages form the amplifiers.
The device will periodically send (every ~100ms) a REQ message to the server which has to be answered by the server via a RSP message, containing the MUTE STATE the device should use.
REQ MSG
Message ID “0” Client -> Server as request the MUTE state
INX_REMOTE_0
RSP MSG
Message ID “1” Server -> Client to answer the REQ message
NO MUTE:
INX_REMOTE_1_0
MUTE:
INX_REMOTE_1_1