Holman Engineering developed a Digital Voice Announcement (DVA) System for Olympic Park station. This DVA is able to make up to four simultaneous announcements, with each announcement being able to be played out any combination of twelve audio channels. It automatically generates the content by concatenating pre-recorded phrases together.

This DVA has now been installed at many sites. The main applications are:

• Passenger Information Systems: To make automated announcements to passengers.
• In Vehicular Tunnels: To make automated announcements to motorists. The Holman Engineering DVA has been installed in the Eastern Distributor and Cross City Tunnels.
• In Factories: To make automated announcements to staff about breaks, exercises, etc.