The sound system of the tunnel uses a system of sounding public spaces, which consists of:
- Public switches and control terminals in COKP,
- Tunneling loudspeakers,
- Sound columns and independent sound trumpets, arranged by tunnel,
- Low voltage cable distribution for powering the speakers.
The system is managed from the control center in COKP, where the center of the video system is located, and the control panel of the SOS system, so the on-call operator, who has complete insight into tunnel events, can intervene when needed.