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A hydrophone  is a microphone designed to be used underwater for recording or listening to underwater sound.

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Hydrophone work by transducing (converting) sound waves to electrical voltage. This is achieved by detection of pressure changes in the surrounding environment. The combination of speed over distance, at which the sound wave travels through water or fluid, is proportionate to the changes in pressure, which will in turn reflect the nature of the electrical output transmitted. Piezoelectric materials are considered ideal for the building of hydrophones. This material can change its form and helps to generate ‘electrical potential output’ in response to mechanical or external pressure variations.

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Cetacean Research ™ hydrophones are manufactured using superior transducers encapsulated in a durable polyurethane. Cetacean Research Technology (CRT) also carries Sensor Technology hydrophones.

CRT offers both hydrophones and hydrophone systems

An extra-rugged version of the C55 in a shape that allows it to be towed behind a boat with less flow noise... more

Directional receive pattern with very wide frequency response for monitoring ultrasonic signals not detectable by competing brands... more

Cetacean Research ™ Hydrophone Specifications Comparisons

notes:

† Requires a preamplifier with 100MΩ input impedance, such as the Reson VP1000 or Reson VP2000 preamplifiers, or the USB Dual Pre, which has 330kΩ impedance. If a typical preamplifier with 1MΩ input impedance is used then the following will occur:

‡ CR1 series and CR3 hydrophones are individually spot calibrated at the factory; calibration guaranteed between -5°C and 30°C.

CR2 hydrophones are not individually calibrated, but calibrated frequency response measurements can be performed for an additional fee.

* Cable terminated with male BNC connector (longer cable optional)

Cetacean Research ™ Hydrophone Specifications Comparisons

* Transducer Sensitivity + Preamplifier Gain = Effective Sensitivity.
** 1,000 meter versions are available. Append "-1k" to the model number to order a hydrophone with a depth rating >1,000 meters.
*** Connectors are rated to a depth of 7,000 meters; see below (or to the side) for mating connector and cables.

Signal Output

Female BNC connector

Box Dimensions [mm]

110 long (including connectors) x 90 wide x 50 high

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Joseph R. Olson - Cetacean Research Technology with assistance from Diane Allen, Artemis Computing

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Overview and comparison of specifications for Cetacean Research hydrophones and Cetacean Research hydrophone systems. Includes both audio-band and ultrasonic hydrophones for underwater noise measurement, underwater sound analysis, and for the study of cetaceans, the natural underwater environment, and other underwater acoustics.