Public Talkback - Overhead Speaker

Required Parts And Tools

• Output Speaker (may be overhead or in wall mounted)
• Shure MX393 Boundary Mic
• RDL STM-1 Preamp
• F-XLR Tail
• RDL ST-VOX1
• 22/2 audio cable
• B-connectors
• Speaker Amplifier (Fosi or comparable)
• Ceiling Speaker (6 1/2")
• Fish Tape or Glow Rods
• Electrical Tape
• Wire Stripper

Installation Instructions

Mounting the Audio

1. Decide where the STM-1 will be located, knowing the MX393 mic will need to reach it.
2. Using a stud finder, determine the best location to route the 22/2 cable
3. Cut a hole into the drywall, large enough to fit a mud ring into it securely.

   

4. Using glow rods or fish tape, pass the 22/2 behind the wall routing to the STM-1

   Note: The wires of the XLR will wire to the +, -, and ground Input on the STM-1.

5. Secure a pass through plate to the mud ring mounted for the XLR just ran
6. Place the MX393. This mic line will connect the mic line to the STM-1
7. Mount the STM-1 above the ceiling
8. Wire the red to the + and black to the ground power terminals on the STM-1.
9. Cut a length of 22/2 from the STM-1 to the camera. Strip the jacket on both ends. Cut away the bare wire and plastic surround the cable inside. Strip away a small piece of the red and black jackets revealing the bare copper wire.
10. A short piece of 22/2 cable will also be needed (approx. 1 inch).
11. Strip the jacket from the cable and remove all contents keeping only the red cable.
12. On both ends of the red cable, strip off a piece of the jacket. Connect one end of the 1 inch audio cable to the +PWR terminal and connect the other end into the +PHNTM terminal.
13. Run another length of 22/2 cable from the STM-1 to the a ST-VOX1

Wiring the ST-VOX1

1. Connect a line from the High Z of the STM-1 to the ST-VOX1 to the center port of the input on the device labeled as a line diagram (see wiring diagram)
2. From the Camera, run three lines of 22/2. One will be connected to the input and two will be connected to the output.
3. Connect the 22/2 connected to the camera input to the first port on the line diagram input. Connect one of the 22/2 connected to the camera output to the input port labeled Line. The third 22/2 will connect to the speaker.

   Note: All lines connected to the ST-VOX1 utilize shared ground