The ST-VP2 can be wired into any line-level input of a paging amplifier. A line-level music source may be provided from a receiver, satellite decoder, tape or CD source. A line-level voice source may be provided from a telephone paging system at line level, or from a microphone which has been preamplified up to line level (See RDL STM-1, STM-2, STM-2X, STM-3, STM-LDA3 Microphone Preamplifiers). When a page is initiated, the module automatically senses the audio at the input, turns the music down to the desired level, and automatically fades the music back up after the page is completed. The VOICE input is completely turned off by the module until the next paging signal is received. Setup is made easy by two LED indicators at the front of the module. LEDs are provided to show correct operating level for each of the two inputs.

The music input provides an AGC/Compressor which transparently produces a consistent audio level for varying music sources and protects against excessive music levels which would otherwise mask the voice signal during voice-overs.