Connecting a Shure MX400SMP to an EX-LOGIC
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 MX400SMP surface-mount microphone preamp 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.
Goal
After completing the steps in this article, you will be able to connect a Shure MX400SMP to a Tesira EX-LOGIC. This will allow your Tesira configuration to control the LED's on the MX400SMP.
Note that Shure MX series microphones use phantom power to power its LED's. Therefore, no external power supply is required for this application.
Pinout
The Shure MX400SMP is a surface-mount mic preamp that is designed to work with Shure MX405, MX410, and MX415 gooseneck microphones, each of which has either a single-color LED ring or a bi-color LED ring, depending on the model. The MX400SMP comes with a 5-pin XLR connector. The pinout of this connector is shown in the table below:
| XLR Pin | Function |
|---|---|
| Pin 1 | Audio Ground |
| Pin 2 | Audio - |
| Pin 3 | Logic Ground |
| Pin 4 | Audio + |
| Pin 5 | LED In |
Wiring
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.
Note that Shure MX series microphones use phantom power to power its LED's. Therefore, no external power supply is required for this application. Use the Logic Output block in the Tesira configuration.
Each MX400SMP uses one logic (output) terminal on the EX-LOGIC, which means that a maximum of 16 MX400SMP's can be connected to a single EX-LOGIC. The diagram below shows a typical wiring scheme for a single MX400SMP:
LED control
Shure MX405, MX410, and MX415 gooseneck microphones have a bi-color LED ring. This 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).
Shure MX405R, MX410R, and MX415R gooseneck microphones have a single-color LED ring. This LED ring will light up when there is less than 1V across pins 3 and 5 (i.e., logic output in the low state), and it will turn off when there is 5V across pins 3 and 5 (i.e., logic output in the high state).
Further reading
- Once the device is physically connected to the EX-LOGIC, you'll need to program it. See EX-LOGIC programming for more information.
- Muting microphones with logic