NAUTA scientific

sensing the real world

Cetacean Research Technology CR1A

The CRT CR1A hydrophone is an excellent multi-purpose hydrophone.
This non-preamplified hydrophone is ideal for the detection and recording of very loud signals, such as those from pile driving, air guns, or underwater demolition operations.
It can be used with an external preamplifier for recording and listening to the quieter sounds of cetaceans and other underwater sources. Terrestrial applications for the CR1A include vibration detection and using it as a geophone. The hydrophone comes with an extra tough polyurethane-jacketed coaxial cable. The cables can be terminated with either BNC or mono phone plug connectors.

All CR1A hydrophones are individually spot calibrated at the factory.
Specifications CRT CR1A
Linear Frequency Range (±3dB) [kHz]: 0.00016 to 48
Useable Frequency Range (+3/-20dB) [kHz]: 0.00005 to 68
(see note †)
Sensitivity [dB, re 1V/µPa]: -199
Preamplifier Gain [dB]: N/A
SPL Equiv. Self Noise at 1kHz [dB, re 1µPa]: 38dB
Power Requirement [Vdc]: N/A
RMS Overload Acoustic Pressure [dB, re 1µPa]: N/A
Maximum Operating Depth [m]: 500
Operating Temperature Range [ºC]: -25 to 60 (calibration guaranteed in the range -5..+30C)
Capacitance [nF]: 12
Dimensions [mm]: 85 L x 32 dia
Coaxial Cable Length: 15 meters, Cable terminated with male BNC or mono phone plug connector (longer cable optional)
Directionality: omnidirectional below 10kHz
Battery / Connector box: power not required
note †
Requires a preamplifier with 100MOhm input impedance, such as the Reson VP1000  or Reson VP2000  preamplifiers (on the left).

If a preamplifier with 1MOhm input impedance is used, then the low frequency -3dB point will be at 16Hz instead of 0.2Hz and the -20dB point will be at 2Hz instead of 0.02Hz.
  • extra length ruggedized cable
  • custom orders not listed above
  • hydrophone may be used with either the optional Reson VP1000 or Reson VP2000 preamplifiers.