Long-standing audio difficulties at Madrid's Atocha station have been addressed by the specification of an AXYS Intellivox system. Invited to supply a system that would provide clear, coherent announcements at a specified sound pressure level, systems integrator IKUSI worked in close conjunction with local AXYS distributor SPA/STICON during the design and final adjustment stages.
An absence of acoustic treatments that contributes to an RT60 (reverb time until decay to -60dB) of 4.5 seconds, ambient noise of between 65-71dB, and the need to deliver regular messages across multiple levels and platforms were among the issues that IKUSI and SPA/STICON had to confront during the Atocha project.
Selected to provide coherent sound to the specific areas in which it is required, while steering it away from reflective surfaces that would give rise to unwanted reverberation, the AXYS specification comprises 10 DS-500, eight DS-180, 33 V-90 and 11 H-90 column speakers, with power from five PB-800 and three PB-400 amplifiers. Proprietary AXYS software enabled the directory and other system parameters to be tailored specifically to the venue.
The new system more than satisfied requirements: subsequent to installation and fine-tuning, the all-important STI (sound intelligibility) rating was found to be 0.5 in the lobbies - better than expected. Once adjusted to an emission level of 78dB, the average was 0.45 STI. On the platforms the average was 0.54 STI, while after adjusting the system to an emission level of 83dB the average was 0.5 STI.
"The improvement has been very significant and now the messages are clear all over the station, with an acceptable volume," remarked the client, Spanish railway operator RENFE.