Each metering station houses an industrial embedded computer using the free Unix variant FreeBSD, with its sound card connected to an external microphone.  The microphone is positioned approximately two metres above the roof of the unit’s casing, usually on a metal pole but in some cases secured to a wall.
In the development of this station considerable use was made of the experience gained by Wireless Leiden during their work on roof-sited computers.

All data are sent real-time to a central database via the internet connection of the premises where the meter is placed.  The same route is used for continuous monitoring of the station using Nagios. 

Each unit takes measurements for 24 hours a day, 365 days a year, generating 86,400 measurements each day and over 31 million data points per year.  The unit uses approximately 10W of electrical power, costing in the region of €5 per year.

All data are stored in a central database, a heavy-duty processor with double hard disks and back-up power supplies.  The server is in a cybercentre in Amsterdam where it has a high-speed (100Mbit/s) internet connection.  FreeBSD, Apache, PHP, MySQL, rrdtool, Perl, typo3 and many other open-source software languages are used by the server.
It also houses the Geluidsnet website and all client reports.