One popular application for the EX-LOGIC is to interface with conferencing microphones that feature mute switches and LED indicators, and Shure is a leading manufacturer of such microphones. This article describes how to physically connect a Shure MX395-LED microphone to a Tesira EX-LOGIC.
Note that even though this article shows diagrams for only the EX-LOGIC, the logic I/O terminals that are built into Tesira servers and TesiraFORTÉs can be used for the same purposes as an EX-LOGIC.
After completing the steps in this article, you will be able to connect a Shure MX395-LED to a Tesira EX-LOGIC. This will allow your Tesira configuration to control the LED's on the MX395-LED.
Note that Shure MX series microphones use phantom power to power its LED's. Therefore, no external power supply is required for this application.
The Shure MX395-LED is a boundary microphone with a bi-color LED ring. The MX395-LED comes with a 5-pin XLR connector. The pinout of this connector is shown in the table below:
|Pin 1||Audio Ground|
|Pin 2||Audio -|
|Pin 3||Logic Ground|
|Pin 4||Audio +|
|Pin 5||LED In|
The audio conductors on the microphone will connect to the audio inputs on the Tesira device like a typical microphone. The LED and Logic Ground conductor will connect to the EX-LOGIC. The LED In conductor connects to a logic output, and the Logic Ground connects to any of the ground terminals on the EX-LOGIC.
Each MX395-LED uses one logic input terminal on the EX-LOGIC, which means that a maximum of 16 MX395-LED's can be connected to a single EX-LOGIC. The diagram below shows a typical wiring scheme for a single MX395-LED:
The microphone's LED ring will light up green when there is less than 1V across pins 3 and 5 (i.e., logic output in the low state), and it will light up red when there is 5V across pins 3 and 5 (i.e., logic output in the high state).