HYDRORADIO is a platform for monitoring both natural and anthropogenic sounds in response. It addresses the sonic ecology created by increasing human activities, formed by ocean traffic, sonar activities and industrial extraction. This invisible sonic infrastructure affects both the orientation and communication of non-humans. The HYDRORADIO platform is controlled by self-developed (radio) buoys that act as speakers of the North Sea. They broadcast underwater sounds from various locations around the Dutch coast via a live radio link. Visitors are invited to experience and interpret underwater sounds, vibrations and frequencies emitted by unseen sonic infrastructures in the installation. In addition, the platform functions as an open-source movement, which stands for the development of own tools, the collection of local data as an alternative to the already existing, often non-public data extracted by sensory networks in our oceans that are involved in international governmental activities.