Brüel & Kjær hydrophones are individually calibrated, waterborne‐sound transducers. Each hydrophone has a flat frequency response, is omnidirectional over a wide frequency range and has shielded-element construction. Also, they are completely waterproof, corrosion-resistant and withstand high levels of salinity. If you are looking for high-quality hydrophones for laboratory or deep-sea research - you've come to the right place.


Each Brüel & Kjær hydrophone is submitted to an extensive ageing and temperature stabilizing procedure before being individually calibrated. Individual calibration data and frequency response curves are supplied with each hydrophone. The receiving sensitivity calibration of the hydrophones is traceable to international standards.

All B&K hydrophones provide a flat frequency responses, as shown in this figure:

Hydrophone Frequency ResponseMeasurements made in water tank in free-field conditions achieved by means of pulse techniques using a Brüel & Kjær PULSE™-based calibration system.




All hydrophones in our range, provide great omnidirectional characteristics. The individual hydrophone directivity patterns in water are shown in the figure below.


Hydrophone dispersion


The polar directivity patterns were measured in free-field conditions achieved by means of gating techniques in a water tank.This method requires a standard hydrophone as a projector and the unknown hydrophone as the receiver whose polar directivity pattern is to be determined.