The ellipsoid loudspeaker units are networked and connected to the power supply. Their raspberry-coloured bodies are made up of plastic semi-shells connected by a band of sound-transparent, perforated metal. Each is crowned with a scratch-resistant, stainless steel plate with an engraved text.

This outer shell contains electronic components combined to create a single element which is accommodated in a second, separate protective covering. The acoustic signal is directed outwards by a sound cone within the ellipsoid. The construction is sufficiently vandalism-proof, weatherproof and frostproof. Any refuse which is kicked or thrown in will fall out of the openings at the bottom. Each ellipsoid is screwed onto a steel tube and fixed into the ground with its own foundation so that it cannot be tipped over.

The electronic components used have been combined together to create a weatherproof, low-maintenance module which has been sealed with resin. The broadband loudspeaker employed has a minimised power of 5 watts. The operating costs are low. The files for the composition have been compressed into MP3 format and are played using a flash memory with direct amplification to avoid mechanical wear and tear.

The length of the pauses and the random process for the sequence in which the sound pieces are played is controlled by a processor. Configurations such as volume or time parameters can be set via a temporarily activated WLAN. The status of the ellipsoids will be monitored for maintenance purposes and transmitted to a service centre via GRPS.