What is the purpose of using a mud ring in low-voltage rough-in?

• A. To allow cables to pass through a finished wall
• B. To insulate cables
• C. To anchor cables to studs
• D. To reduce noise

Answer: (A)

Mud rings (plaster rings) are used to create a finished, flush opening around a low‑voltage box as the wall is being finished. By placing the ring around the box, the wall finish—whether drywall or plaster—can be applied up to the edge without clogging or crowding the box, and cables can pass cleanly through the finished wall into the box. In other words, it provides the proper depth and edge support so the box remains accessible and the faceplate sits flush after mudding/drywall. This function is separate from insulation, anchoring to studs, or reducing noise.