
Benthowave Instrument Inc.
Underwater Sound Solutions www.benthowave.com
Sensitivity FFVS @ 1 kHz:
-196.5 + Preamp Gain, ± 2 dB V/μPa.
Bespoke, Refer to Graph of FFVS vs. Frequency. Free-field Voltage Sensitivity.
Refer to Graph of Pressure Noise Density,Referred to Input (RTI), in μPa/√Hz.
In Water: 10 Hz to 260 kHz at ±3 dB V/µPa.
In Air: 10 Hz ~9 kHz at -3 dB V/µPa.
Programmable Gain Preamp: 30, 60 dB.
Gain Selection Voltage:
(Programmable Gain
Preamp)
CMOS/TTL Compatible
Logic Low 0: Gain Selection Wire to COM or 0 to +0.8 VDC.
Logic High 1: Gain Selection Wire Open or +2.4 VDC to Vs.
1. Default: -3dB Bandpass Pass Filter: 4 Hz to 260 kHz.
2. Bespoke High Pass or Band Pass filter. Specify when ordering. Note: Minimum high pass filter f-3dB: 4 Hz.
1. Reduce Noise. Both ocean ambient noises and the self-noises of electronic devices decrease when frequency increases. It is
recommended to choose a built-in high pass filter to reject noises in low frequency range. For example, if you are interested in the
signals greater than 200 Hz, you may specify a high pass filter with -3dB cut-off frequency at 100 Hz to improve signal to noise ratio
of the signals of the interest.
2. Avoid Saturation. When there are strong low frequency noises, disturbances, and/or vibrations, resulting from rough surface
waves and/or mechanical movements of the platform, it is recommended to specify a high pass filter to avoid hydrophone
saturation in these low frequency ranges.
Omnidirectional and Toroidal. Refer to Graph of Directivity Pattern.
To reject Electromagnetic Interference (EMI) over long cable, the differential (balanced) output is recommended.
Vomax = (Supply Voltage Vs - 4) Vpp.
(Supply Voltage Vs –3.4) Vpp.
197 or [20*log(Vomax/2.828) –Sensitivity], whichever is less. in dB μPa.
Acceleration Sensitivity:
101.5 dB re µPa/(m/s²) at Acoustic Axis; ≤ 101.5 dB µPa/(m/s²) at other directions.
Maximum 300 m or 3 MPa pressure and limited by the cable length if the cable has wire leads or a non-waterproof connector.
1. Default: Free Hanging (FH)
2. Free-hanging with Male Underwater Connector (FHUWC)
3. Thru-hole Mounting with Single O-ring (THSO)
4. Thru-hole Mounting with Double O-ring (THDO)
5. Bolt Fastening Mounting (Plastics) (BFMP)
6. Bolt Fastening Mounting (Stainless Steel) (BFMSS)
Please refer to online document AcousticSystem.pdf for a complete list of Mounting Options and more details.
Four Conductor Shielded Cable (SC)
Six Conductor Shielded Cable (SC)
1. Default: 10 m.
2. Custom-fit up to 200 m.
SE: Single ended Output, DF: Differential Output.
1. Default: Wire Leads (WL)
2. Male BNC (BNC) (Max. Diameter Φ14.3 mm), for SE ONLY.
3. SMA (Plug, Male Pin) (SMA), Voltage Rating: 335 VRMS Continuous. (Max. Diameter Φ9.24 mm), for SE ONLY.
4. SMC (Plug, Female Socket) (SMC), Voltage Rating: 335 VRMS Continuous. (SMC) (Max. Diameter Φ6.4 mm), for SE ONLY.
5. 1/8" (3.5mm) TRS Plug (TRS) (Max. Diameter Φ10.5 mm), for SE or DF.
6. XLR (pin) (XLR) (Max. Diameter Φ20.2 mm), for SE or DF.
7. MIL-5015 Style (pin) (MIL) (Max. Diameter Φ30 mm with 3 contacts), for SE or DF.
8. Underwater Mateable Connector (pin) (UMC) (Max. Diameter Φ21.5 to Φ35 mm), for SE or DF.
9. +9VDC Battery Snap (BS)
Underwater Mateable Connector is for uses underwater. Other connectors and wire leads are for dry uses and are not
waterproofed.
+9 VDC Battery, Marine Battery, Automobile Battery, Fixed DC Linear Power Supply, Not Included.
DO NOT use variable power supply whose maximum supply voltage is higher than the rated voltage.
DO NOT use switching mode DC power supply.
ΦD = Φ21 mm, Length ≥ 90 mm and actual length depends on Mounting Parts.
≥ 0.55 kg with 10m cable. Actual weight depends on Mounting Parts, Cable Types and Length.
-10°C to +60°C or 14°F to 140°F.
-20°C to +60°C or -4°F to 140°F.
Sound Measurement in Air: The hydrophones can be used to detect sounds in air. The sensitivity in air is same to the one in water in low frequency range.
Wiring Information of Hydrophones with Fixed-gain Preamps:
BNC Male/SMA/SMC,
9V Battery Snap
XLR Plug and
9V Battery Snap
TRS Plug and
9V Battery Snap