SE=SL-TL+AG-NL
BII7120 Series Low Noise, Low Power, and Low Frequency Hydrophone: Noise Level Below Sea State Zero
BII's low noise hydrophones are optimized to possess self noise levels below sea-state zero with omnidirectional response in low frequency range and toroidal response
in high frequency range. Its streamlined hemispherical dome minimizes drag force and hydrodynamic noise. The power consumption can be customized to be
quiescent current at 5VDC
for battery powered underwater instrumentation. A spatial array of multiple hydrophones can be set up for directional measurement system.
The hydrophones can measure underwater sounds and pressure fluctuations down to
seismic, ocean traffics, industrial noises, precipitations, biologics, ...
With these low power hydrophones, battery and system lifetimes are extended, and lighter portable systems with lower-capacity batteries can be achieved. Its compact
small size avoids interferences to acoustic field under test. The preamplifier integrated in the hydrophone can drive cable up to 200m without signal loss. Available cable
terminals include audio connectors (TRS, XLR), BNC, and underwater mateable connectors.
The housing and mounting part are corrosion resistant plastics and/or stainless steels.
Underwater Sound Listening, Recording, and Communication
Typical Applications
Underwater Sounds Recording, Listening, and Communication, Marine
Bioacoustics, Passive Acoustic Monitoring (PAM System).
Oceanic Ambient Noise Measurement, Surface Waves, Ocean Turbulences,
Hydrodynamics, Marine Geophysics.
Questions
How do I set up my professional sound recorders to work with BII Hydrophones?
1. BII hydrophones have their own DC power supply to support Line Input of recorders, and Do NOT use phantom power 48V which may destroy the hydrophones.
2. Maximum Input Level (Line Input) of recorders should be large enough to avoid saturation or clipping during recording.
Equivalent Input Noise of recorders should be low enough for the recorders to be sensitive to weak signal of the interest.
3. Sampling Rate of the recorder should be fast enough to avoid missing high frequency sound of the interest. Generally, the Sampling Rate should be at least two times
greater than the maximum frequency of sound.
4. Calculate the memory size of data storage according to sampling rate, resolution, sampling channels, and recording time, and use suitable recording media.
5. Calculate battery service life according to battery power and consuming current.
6. When the cable is greater than 5m, balanced signal or differential signal is recommended to be in use over the cable.
How do I playback the recorded sounds in water?
System Setup: Recorder (Recorded Sounds) with Line or Phone Output ->
Benthowave Instrument Inc.
Underwater Sound Solutions
BII Hydrophone
www.benthowave.com
BII7123FG
0.1Hz infrasonic
sounds: Surface Waves (Wave-height Sensor), Turbulences,
Headphone
Speaker
Sound Recorder
DAQ + Computer
Oscilloscope
BII Hydrophone
Sound Recorder
Sound Transmitter
Coastal/Offshore Processes, Engineering & Management, Wave-Structure
Interaction, Wave-height Sensor, Wave and Tide Recorder/Logger.
Battery-Powered Instruments: Sonobuoy, Recorder, Transponder, Acoustic
Release...
Audio Power Amplifiers
->
Impedance Matching Device
Page 1 of 6
PA
+
Impedance Matching
BII Transducer
BII Transducer
->
Transducers
(Projectors).
600µA
Need help?
Do you have a question about the BII7120 Series and is the answer not in the manual?
Questions and answers