DG81782: RailBAM (Bearing Acoustic Monitor) equipment installed near Swaythling. This has an array of 16 microphones that can listen to a passing train and identify whether the axle bearings are sounding normal or making a different sound which might indicate the onset of failure in the future. Manufactured by Trackside Intelligence and installed by Siemens, the RailBAM product installed in the UK is a European first and the first to be employed to monitor passenger vehicles.

In this picture you can see that hatch opened to allow the microphones pick up bearing noise from 444044.