Technology confirms ASL's standing in public address and voice alarm sectors 
ASL's DANS system improves the sound quality of its PA / VA ranges
UK-based ASL Safety & Security has developed an intelligent ambient noise sensing system that improves the audibility of train platform announcements.
Conventional noise sensing equipment at transport hubs takes a crude sample of background activity before the broadcast, and cannot adjust for varying background noise. ASL's Dynamic Ambient Noise Sensing (DANS) system uses digital signal processing to distinguish ambient noise from the announcement and continuously optimise the volume level.
This ability to address the familiar problem of garbled announcements confirms ASL's leadership position in the global public address and voice alarm sector.
Peter Andrews of ASL said: "The technology is ideal for noise abatement areas where local councils are under pressure to reduce noise pollution for people living near train stations. In normal practice, the volume level of announcements has to be set to achieve audibility above passing trains. As speaker coverage in an average station has increased in recent years, so have complaints."
Mr Andrews continued: "The use of Dynamic ANS throughout rail networks would allow default volume levels to be adjusted to much lower levels than possible at present, improving the passenger experience as well as the lives of nearby residents."
Dynamic ANS can be part of a new installation or retrofitted to legacy PA equipment. Usage is not limited to the transport sector and the technology will be of interest to stadium managers, particularly those responsible for sports arenas, which are characterised by rapid changes in crowd noise. If an important announcement needs to be made volume levels will adjust during the message.
ASL Safety & Security is the market leader in the PA / VA systems infrastructure projects sector. The company's analogue and IP products cover conventional and networked Voice Alarm systems, Voice over Internet Protocol (VoIP), Long-Line PA and PC/DVA applications. ASL has also developed iVENCS, a management system for transport hubs that offers a scalable solution allowing all of a site or network's subsystems to be controlled through a single 3D user interface. iVENCS has been implemented as part of an £800m refurbishment of St Pancras International Station, the London terminal for Eurostar.
